Each box comes with the story of how people figured it out. Here they are, merged into one line through time, so you can see which ideas grew up together.
Early humans, probably Homo erectusWonderwerk Cave, Northern Cape
Deep inside Wonderwerk Cave, far from the entrance, scientists found ash from burnt plants and bits of burnt bone in layers about a million years old. Tiny cracks and colours in the bone show it was heated where it lay. It is among the oldest secure signs of people using fire, though some researchers argue for older ones.
Why it mattered. Fire gave early humans warmth, light, safety and cooked food, the first chemistry anyone ever controlled.
Homo erectus ("Peking Man"); dug up from the 1920sZhoukoudian, near Beijing
Burnt bones and thick dark layers in the Zhoukoudian caves were long taken as the hearths of Peking Man. A careful study in 1998 found burnt bone but no clear ash or hearths, so whether these people kept fires there is still argued about.
Why it mattered. It shows how hard it is to prove who first tamed fire, and why old claims need testing.
Possibly Neanderthals; found by Ivan Turk's team in 1995Divje Babe cave, near Cerkno, Slovenia
In 1995 archaeologists found a cave bear cub's thigh bone with round holes in a row. The National Museum of Slovenia shows it as a Neanderthal flute. Many scientists think the holes were more likely bitten by hyenas or other carnivores, so it may not be a flute at all.
Why it mattered. It shows how hard it is to prove that a bone with holes was made to make music.
Early modern humans (Aurignacian culture)Geissenklösterle cave, Swabian Jura, Germany
Flutes carved from a swan's wing bone and from mammoth ivory were found in the Geissenklösterle cave. In 2012 a team from Oxford and Tübingen radiocarbon dated bones from the same layers to about 42,000 to 43,000 years ago. That made them a few thousand years older than anyone had thought.
Why it mattered. They are among the oldest musical instruments ever found, and they already have finger holes to change the note.
Nicholas Conard's team, University of TübingenHohle Fels cave, near Ulm, Germany
In 2008 archaeologists dug up 12 pieces of a flute carved from the wing bone of a griffon vulture. Put back together it is about 22 centimetres long and has five finger holes. The team published it in the journal Nature in 2009.
Why it mattered. It proved that a real musical tradition existed when modern humans first spread across Europe.
The oldest quern found so far comes from Abu Hureyra in Syria, from about 9000 BCE. It is a saddle quern: a flat or slightly hollow bottom stone and a smaller stone that you push back and forth. Grain caught between them is crushed into flour.
Why it mattered. Crushing food between two hard surfaces is the oldest grinding idea, and a mixer grinder still crushes food, only much faster.
Early farmers of the Jiahu culture; studied by Zhang Juzhong and colleaguesJiahu, Henan province, China
Six complete flutes, and pieces of about 30 more, were found in graves at the Neolithic village of Jiahu. They are made from the wing bones of red-crowned cranes and have five to eight holes. In 1999 scientists played the best one and heard a scale not far from do-re-mi.
Why it mattered. They are among the oldest playable instruments in the world, so we can actually hear the notes ancient people chose.
People of ÇatalhöyükÇatalhöyük, Anatolia (today Turkey)
In one of the world's oldest towns, houses were packed so tightly that people walked across the rooftops and climbed in through holes in the ceiling. Those same holes were the only ventilation, so smoke from the open hearths and ovens inside drifted up and out.
Why it mattered. Hot smoke rises, and the oldest kitchen chimney was simply a hole above the fire.
Neolithic peopleFrance, and later across Europe, Asia and the Americas
Some of the oldest known holes cut into living people’s skulls come from Neolithic graves in France. At one site, about a third of the skulls had been trepanned. Many show healed bone, so patients often survived.
Why it mattered. It is the oldest known brain surgery, though we can only guess why it was done.
A cylinder seal in the British Museum, dated to about 3100 BCE or earlier, seems to show a woman playing a long-necked lute. The idea is simple: strings stretched along a neck over a hollow body. Press a string against the neck and it plays a higher note.
Why it mattered. Every guitar still works this way: a string, a neck to shorten it, and a body to make it louder.
Unknown merchants and scribesMesopotamia; later Greece and China
People in ancient Mesopotamia are thought to have counted on boards with lines and pebbles. The oldest counting board that survives, the Salamis tablet from Greece, dates to about 300 BCE. Written records of the Chinese abacus go back to about the 2nd century BCE.
Why it mattered. Each bead or pebble stands for a digit in a place, the same idea a computer uses for numbers today.
Some historians think the Sumerians of Mesopotamia were the first to reckon on a counting board, moving pebbles between ruled columns. No board survives, so the date is uncertain.
Why it mattered. Moving tokens between columns is the first place-value machine: each column worth more than the one beside it.
Harappan buildersMohenjo-daro and Harappa (today Pakistan), Lothal and Dholavira (today India)
Many houses in the Indus Valley cities had a bathing floor and a toilet that drained into covered brick channels along the streets. It was one of the earliest city-wide drainage systems anywhere.
Why it mattered. Carrying waste away from homes is one of the oldest public-health ideas of all.
People of the Indus Valley CivilisationMohenjo-daro (today in Sindh, Pakistan)
Builders made a waterproof brick pool about 12 m long and 7 m wide, filled from wells and emptied by drains. It is one of the oldest public water tanks known. As far as we know, its water was not heated.
Why it mattered. It shows how long bathing has mattered in South Asia, long before anyone could heat water on tap.
Frying is believed to have first appeared in Egyptian cooking during the Old Kingdom, around 2500 BCE. The exact date is uncertain, because cooking leaves few traces. Cooks heated animal fat or plant oils in shallow pans over fire.
Why it mattered. Hot fat is the oldest way to make food brown and crisp, the result an air fryer tries to copy.
People of the Indus Valley civilisationIndus Valley (today India and Pakistan)
Grinding stones from the Indus Valley civilisation, around 2500 BCE, look a lot like the sil-batta still found in Indian homes: a flat stone (the sil) and a rolling stone (the batta). It has many names, like shil nora in Bengali, pata-varvanta in Marathi and ammi in Tamil. For thousands of years it ground chutneys, spice pastes and soaked lentils.
Why it mattered. The mixie was built to do the sil-batta's job, which is why Indian cooks expect so much from it.
There is evidence that evaporative cooling was used in Egypt as early as the Old Kingdom. Paintings show servants fanning water jars made of porous clay. Water seeps through the clay and evaporates from the outside, which chills what is left inside.
Why it mattered. It is the same trick every air conditioner uses: a liquid that evaporates carries heat away with it.
Unknown Egyptian healers; described by Grafton Elliot Smith in 1908Naga ed-Der, Egypt
Archaeologists digging old graves in Egypt found two skeletons with splints still tied on. One broken forearm was held by three pieces of acacia bark wrapped in linen. A broken thigh bone had four wooden splints bound around it.
Why it mattered. People were already trying to hold broken bones still so they could heal.
At Lothal, a Harappan town on the Gujarat coast, archaeologists found a huge brick basin about 218 m long beside an old channel of the Sabarmati. Many read it as one of the world's earliest docks, where boats floated in on the tide; others think it was a water tank. Either way, boats were loaded and floated along this coast thousands of years ago.
Why it mattered. It is a reminder that people handled floating and loading long before anyone wrote down why things float.
Archaeologists digging at Pyrgos on Cyprus found a large workshop, dated to about 4,000 years ago, with stills, jugs and bowls for making scented oils. From residues in the pots they recreated perfumes of pine, coriander, bay and rosemary.
Why it mattered. It shows that making smells on purpose is one of the oldest crafts people have.
Workers of the nomarch DjehutihotepDeir el-Bersha, Egypt
A painting in the tomb of Djehutihotep shows 172 workers hauling a colossal statue, nearly 6.8 m tall and around 58 tonnes, on a wooden sledge. A man stands on the front of the sledge pouring water onto the sand in its path. In 2014, physicists in Amsterdam showed why: the right amount of water stiffens the sand so the sledge doesn't plough into it, roughly halving the pull needed.
Why it mattered. It is one of the oldest pictures of someone deliberately changing friction.
Diviners of the city of MariMari (Tell Hariri), Syria
In the 1930s, archaeologists digging the palace of the ancient city of Mari found more than thirty clay models of sheep livers, each marked with an omen. They date to the Old Babylonian period, nearly 4,000 years ago. They are among the oldest detailed written records of liver reading.
Why it mattered. They show that people watched the liver's shape and marks closely long before anyone knew what it did.
A baked clay model of a sheep's liver, now in the British Museum, is divided into about 55 boxes, each with writing. Priests sacrificed a sheep, looked at its liver and matched every bump and groove to an omen. The model was probably used to teach trainee diviners.
Why it mattered. It is one of the oldest known models of a body organ, made to be studied in detail.
The Edwin Smith Papyrus lists 48 injury cases, from the head down to the spine. For each one it gives the examination, the diagnosis and a treatment, including splints and bandages for broken bones. It is mostly practical, not magic.
Why it mattered. It is the oldest known surgical text, and it treats broken bones in a step-by-step way.
An Egyptian surgical scroll, now called the Edwin Smith Papyrus, describes 48 injuries. It mentions the folds of the brain, the fluid around it, and notes that a broken neck can leave a person unable to move or feel their arms and legs.
Why it mattered. It is the oldest known record linking the brain and spine to movement and feeling.
The Edwin Smith Papyrus, a copy of an even older surgical text, describes 48 injury cases. It contains the first known descriptions of the brain’s surface, its coverings and the fluid around it, and notes that head injuries can paralyse the body.
Why it mattered. It links the brain to control of the body more than 3,500 years ago.
Egypt had doctors who looked after the bowels, with a title that meant 'shepherd of the anus', recorded from around 2200 BCE. The Ebers Papyrus, from about 1550 BCE, lists remedies for constipation and other gut troubles. Egyptian doctors thought illness came from blocked channels inside the body, a bit like a blocked river, so they used laxatives and enemas to clear them.
Why it mattered. It is some of the oldest written evidence of people trying to understand and treat the gut.
The Ebers Papyrus is one of the oldest medical texts we have. It has a section on the heart, which it treats as the centre of the body, with vessels called metu running from it to every limb. The Egyptians thought these vessels carried many things, not just blood.
Why it mattered. It is one of the first written ideas that the heart is linked to the whole body through tubes.
The US EPA's history of water treatment says Egyptians reportedly used alum as early as 1500 BCE. Alum makes tiny floating specks clump together and sink, so clear water can be poured off the top. Tomb pictures from about the 15th to 13th centuries BCE show water being settled and siphoned.
Why it mattered. Clumping and settling dirt is still the first step at many water works today.
Queen Hatshepsut’s expeditionPunt (Horn of Africa or Arabia) to Thebes, Egypt
Carvings at Hatshepsut’s temple at Deir el-Bahari show her ships returning from the land of Punt with myrrh, incense and living incense trees in baskets. Temples burned incense every day, and Egyptians used scented oils for the living and the dead.
Why it mattered. Ancient Egypt treated fragrance as precious and sacred, worth sending a fleet for.
Workers in the tomb of Vizier RekhmireThebes (today Luxor), Egypt
The tomb of Rekhmire, a powerful official, shows people grinding tiger nuts, shaping cakes with dates and honey, and frying them. Inscriptions say fat was used. Today the Egyptian archaeobotanist Mennat-Allah El Dorry has recreated the recipe by experiment.
Why it mattered. It is some of the clearest early evidence that people fried food on purpose.
Tutankhamun was buried with fans, including a long gold-covered fan that once held about 30 white and brown ostrich feathers. Its handle says the feathers came from ostriches the young king hunted in the desert east of Heliopolis.
Why it mattered. Fans were so precious in ancient Egypt that a king took them to the afterlife.
Mouth organs called sheng and yu are mentioned on oracle bones from about 3,000 years ago. A sheng has bamboo pipes standing in a wind chest, and each pipe hides a tiny reed that swings freely through a slot. Cousins such as the khaen of Laos use the same trick.
Why it mattered. Every harmonium, accordion and harmonica still uses this free reed idea.
A painting in the Egyptian house of Neb-Amun, from about 1300 BCE, shows a rooftop wind scoop called a malqaf. In Persia, tall towers called bâdgir caught the breeze, and some sent it over cool water in underground channels before it reached the rooms.
Why it mattered. Moving air over water cools it by evaporation, the same trick your skin uses when a fan blows on sweat.
A cuneiform clay tablet from Babylonian Mesopotamia names Tapputi, a woman who oversaw perfume-making at the royal palace. It describes her mixing flowers, oil and calamus with water or other solvents, then distilling and filtering them.
Why it mattered. She is often called the first chemist whose name we know, and she was a perfumer.
The Atharvaveda holds charms and hymns against fever, cough, wounds and snakebite, and names healing plants. Ayurveda calls itself an upaveda, an offshoot, of the Vedas. Its dates are uncertain, and historians see Ayurveda’s later, systematic ideas as coming from many sources.
Why it mattered. It is the oldest Indian text with a large body of healing lore.
In the poem Theogony, Hesiod tells how Zeus punished Prometheus for giving fire to people. An eagle ate his liver every day, and every night the liver grew back. Nobody knows if the Greeks really knew the liver can regrow, but doctors still use Prometheus as its symbol.
Why it mattered. It is the oldest famous story about the liver's real superpower: regrowing after damage.
Traditionally c. 6th century BCE (attributed; the text grew over centuries) · No. 048 EndocrineClear
A swelling of the neck gets a name
Sushruta (attributed)Kashi (Varanasi), India
The Sushruta Samhita, an old Sanskrit book of medicine and surgery, describes galaganda: a swelling at the front of the neck that hangs down. It sorts these swellings into different kinds and suggests treatments, from poultices to surgery.
Why it mattered. It is one of the oldest known descriptions of goitre, a swollen thyroid gland.
Sushruta and later editors of the Sushruta SamhitaVaranasi (traditionally)
The Sushruta Samhita, a Sanskrit surgery text, lists about 500 peshi (muscles), with 20 more in women, alongside bones, joints and vessels. Its authors learned anatomy by studying bodies softened in water.
Why it mattered. It is one of the oldest systematic counts of the body's muscles, not far from today's figure of more than 600.
Traditionally dated c. 600 BCE; text compiled over centuries · No. 046 SkeletonClear
Bamboo splints and bone-setting in India
Sushruta (attributed)Kashi (Varanasi), India
The Sushruta Samhita, a great Indian surgery text, sorts broken bones and dislocated joints into types and explains how to pull them back into place. It tells healers to bind the limb with splints made of tree bark or bamboo. It even counts about 300 bones in the body.
Why it mattered. It is one of the most detailed early guides to fixing fractures and dislocations anywhere.
c. 600 BCE by tradition; the text was likely written and expanded over many centuries · No. 040 SkinClear
Seven layers of skin
Sushruta and later editors (attributed)Ancient India (Varanasi by tradition)
The Sushruta Samhita, a great Sanskrit book of surgery, describes the skin (tvak) as seven layers, from a thin outer one that shows the body's colour to a deep one that holds the flesh. Scholars disagree on its age: tradition says about 600 BCE, but many think it was begun in the last centuries BCE and finished centuries later.
Why it mattered. It is one of the oldest known attempts to picture skin as a stack of layers, an idea microscopes would confirm much later.
c. 600 BCE by tradition; possibly several centuries later · No. 040 SkinClear
A new nose from the cheek
Sushruta (attributed)Ancient India
The Sushruta Samhita explains how to rebuild a nose that has been cut off, using a flap of skin from the cheek. The flap stays joined at one end, so it keeps its blood supply while it heals in its new place. It is the first known written record of this kind of operation.
Why it mattered. A living flap of skin that can move and heal elsewhere is the idea at the heart of plastic surgery.
The Sushruta Samhita, an ancient Indian surgical text, describes couching: a needle pushes the clouded lens down and out of the line of sight. Scholars date the text in layers, some of it centuries later than Sushruta himself.
Why it mattered. It is one of the oldest known descriptions of eye surgery, and couching was used for cataract for over two thousand years.
Rub a piece of amber with fur and it pulls on bits of straw and feathers. Later Greek writers credit Thales with noticing this, though none of his own writings survive. The Greek word for amber, elektron, gave us 'electricity'.
Why it mattered. The first recorded brush with electric charge, and the root of the word.
Later Greek writers, starting with Aristotle, say that Thales noticed lodestone, a natural magnetic rock, pulls on iron. He is said to have thought the stone had a soul. The story is second-hand, but lodestone was well known in the ancient world, in Greece, China and India.
Why it mattered. It is the oldest story we have of someone wondering why magnets pull.
Pythagoras and his followers (attributed)Croton, Magna Graecia
Greek tradition credits Pythagoras with finding that a string halved in length sounds an octave higher, and that lengths in ratios 3:2 and 4:3 give the fifth and fourth. The famous story of blacksmiths' hammers is a later legend and doesn't work physically.
Why it mattered. It was the first law of nature written as numbers, and the seed of fₙ = n v ÷ 2L.
A monochord is a single string stretched over a box, with a bridge you can slide. Halve the string's length and it plays a note an octave higher, vibrating twice as fast. Legend credits Pythagoras, but historians say the ideas are older, going back to Mesopotamia.
Why it mattered. Every piano string follows the same rule: shorter, tighter and thinner strings play higher notes.
Sushruta and Charaka (texts attributed to them)Ancient India
The Sanskrit medical texts known as the Sushruta Samhita and Charaka Samhita describe madhumeha, 'honey urine': urine so sweet that ants and flies gather round it. They link it to thirst and wasting, and note that it is more common in people who eat rich food and move little. The texts were compiled over centuries, so exact dates are uncertain.
Why it mattered. It is among the oldest known descriptions of diabetes, and of the link between lifestyle and one form of it.
The Greek thinker Alcmaeon is credited with arguing that the senses connect to the brain and that the brain is where we understand. Only fragments of his work survive, so this is attributed to him by later writers.
Why it mattered. It is one of the earliest known claims that thinking happens in the head.
Iron Age people of the Iberian PeninsulaNorth-east Iberian Peninsula (today Spain)
Some of the oldest rotary querns found so far come from north-east Spain, from around 500 BCE. The top stone turns round and round on the bottom one with a handle, instead of being pushed back and forth. Rotary querns reached Britain by about 400 to 300 BCE.
Why it mattered. Turning in a circle is faster and less tiring than pushing, and every mixer since has used rotation.
Buddhist texts tell of Jivaka, who studied medicine for seven years at Takshashila and became physician to the Buddha and King Bimbisara. The stories were written down centuries later, so they are legend as much as history.
Why it mattered. They show that physicians trained with teachers and cared for monks in the Buddha’s time.
When the tomb of Marquis Yi of Zeng was dug up in 1978, it held a whole orchestra, including six sheng made from gourds and pipes. Water had filled the tomb and kept the instruments safe for about 2,400 years. Their reeds were made of bamboo.
Why it mattered. They are some of the oldest free-reed instruments that survive.
Musicians of Marquis Yi of ZengSuizhou, Hubei province, China
The tomb of Marquis Yi of Zeng was sealed around 433 BCE with a whole orchestra inside, including 65 bronze bells. Among the instruments were two chi, lacquered bamboo flutes blown from the side like a modern flute. The tomb was found by chance in 1978 and the instruments are now in the Hubei Provincial Museum.
Why it mattered. It is the earliest known flute held sideways, the same way as a bansuri or a concert flute today.
During a terrible plague in Athens, the historian Thucydides noticed that people who recovered could nurse the sick safely, because the disease never attacked the same person twice, at least not fatally.
Why it mattered. It is one of the oldest written notes of immunity: surviving a disease can protect you from it.
Greek doctors linked to Hippocrates argued that illness has natural causes, not divine ones, and taught careful watching and note-taking at the bedside. The Hippocratic Oath, a promise to help and not to harm, is credited to this school, though its real author is unknown.
Why it mattered. Observing the patient and "first, do no harm" are still at the heart of how doctors are trained.
Hippocrates and his followers (the treatise is often credited to his son-in-law Polybus)Kos
The Hippocratic book On the Nature of Man says the body holds blood, phlegm, yellow bile and black bile, and that health is their right balance. Hippocratic doctors also stressed careful observation of the patient.
Why it mattered. It is the root idea of Unani, whose name means “Greek”.
Some texts in the Hippocratic collection are said to note that certain illnesses can be eased by things that cause similar symptoms. The Swiss physician Paracelsus voiced a similar idea in the 1500s. It was one idea among many, not a system.
Why it mattered. Hahnemann would later turn this old hint into the centre of a whole system of medicine.
Hippocrates and his followers (attributed)Kos, Greece
The Greek books On Fractures and On Joints explain how to line up broken bones and put dislocated joints back. A wooden bench with ropes and a winch, later called the Hippocratic bench, could stretch a limb. A way of popping a shoulder back with a foot in the armpit was still used 2,000 years later.
Why it mattered. It showed that pulling steadily on a limb, called traction, helps bones slide back into line.
Greek doctors of the Hippocratic school looked closely at urine to judge illness. One of their Aphorisms says that bubbles sitting on the urine point to disease of the kidneys, and a long illness.
Why it mattered. Foamy urine is still a warning sign today: it can mean protein is leaking through damaged filters.
Greek doctors in the Hippocratic tradition are credited with first noting that the thin skin deep in the ear, the eardrum, has something to do with hearing. They had no idea yet what lay behind it.
Why it mattered. It is the first known link between a part of the ear and the sense of hearing.
The Hippocratic text On the Sacred Disease says epilepsy is not a curse from the gods but a disorder of the brain. It says that joy, sorrow, thought and madness all come from the brain.
Why it mattered. It treated the brain, not the heart or the gods, as the source of the mind and its illnesses.
Greek craftsmen; later Roman and Chinese makersGreece, Rome and China
A steelyard is a balance with unequal arms: a small sliding weight far from the pivot balances a heavy load hung close to it. Greek craftsmen used it before Archimedes explained it, and Roman and Chinese steelyards appeared independently around 200 BCE.
Why it mattered. Market traders were using torque balance long before anyone wrote the rule down.
Records suggest that Persians were building yakhchāls, domed ice houses, by about 400 BCE. Their walls were at least two metres thick at the base, made of a mortar called sarooj that resists heat. Ice frozen in shallow pools on cold desert nights was stored inside, packed with straw, through the scorching summer.
Why it mattered. Thick walls that slow down heat are still the first job of every fridge.
In the deserts of Iran, people built tall domed ice houses called yakhchāl with very thick walls. Ice made on cold winter nights was stored deep inside and could last into summer. Sources often say they go back to about 400 BCE, but the exact start is not certain.
Why it mattered. Thick walls slow conduction, and the tall dome lets warm air rise out, so these buildings used heat transfer long before anyone could explain it.
The Greek doctor Hippocrates is said to have boiled water for his patients and then poured it through a cloth bag. The bag came to be called the Hippocratic sleeve. It caught the bits that made water cloudy and smelly.
Why it mattered. It is one of the earliest recorded water filters, a simple version of the first stage in a modern purifier.
Records suggest that Persians were building yakhchāls, domed ice houses with deep pits and thick walls, by about 400 BCE. They stored winter ice through the scorching summer. Houses in the region also used windcatchers, tall towers that pull breezes down into the rooms; Egypt, Iran and the UAE all claim to have invented them.
Why it mattered. Long before machines, people learned to keep cold and move air with nothing but clever building.
Persians built yakhchāls, tall domed ice houses with thick walls and shade walls. Water froze in shallow pools on clear winter nights and was stored underground, sometimes cooled further by windcatchers.
Why it mattered. It showed that shade, wind and night sky could keep things cold with no machine at all.
The Mohist Canon, a text associated with the philosopher Mozi, describes how light passing through a small hole forms an inverted image, and explains the inversion with light travelling in straight lines.
Why it mattered. It's the oldest known explanation of the principle every camera still uses.
Aristotle opened hens' eggs day after day and wrote down what he saw. By about the third day a tiny red spot appeared that beat like a heart. He argued that the body's parts form one after another, not all at once.
Why it mattered. It was the first careful, step-by-step record of how an embryo develops.
Aristotle wrote a short book asking how animals move. He saw that movement needs a fixed point to push against and something inside that pulls, though he thought the power came from the heart and "pneuma", a kind of warm breath.
Why it mattered. He framed the question every later muscle scientist tried to answer.
In his book On the Soul, Aristotle wrote that the two basic tastes are sweet and bitter. Between them he placed oily, salty, pungent, harsh (astringent) and sour, a list of seven or eight flavours.
Why it mattered. It was one of the first attempts to sort tastes into a short list of basics, an idea still used today.
Aristotle taught that heavy things fall towards the centre of the universe because that is their natural place, and that a heavier body falls faster than a lighter one. It matched what people saw with feathers and stones in air.
Why it mattered. It was the accepted answer for almost two thousand years, until careful experiments showed that only air makes the difference.
In his Physics, Aristotle taught that a moving thing keeps moving only while something pushes it. A thrown stone, he suggested, is kept going by the air rushing in behind it. Everyday life seemed to agree: carts stop when the ox stops pulling.
Why it mattered. It set the puzzle for 2,000 years: why does anything keep moving at all?
Aristotle split motion into two kinds. Natural motion, like a stone falling to its home on the ground, needs no push. Violent motion, like a cart being dragged, lasts only while something keeps pushing or pulling it.
Why it mattered. His idea that force makes speed, not change of speed, ruled for about two thousand years.
In his Physics, Aristotle taught that a moving thing needs a mover to keep it going, and that heavier bodies fall faster than light ones. It matched everyday sights like a falling leaf, and it ruled for nearly 2,000 years.
Why it mattered. It set the puzzle every later thinker had to solve: what speed and falling really are.
Aristotle taught that a stone falls because it is heading for its natural place, and that anything pushed sideways moves only while something keeps pushing it. To explain why an arrow keeps flying, he said the air behind it pushes it on. He also thought heavier things fall faster.
Why it mattered. His ideas ruled for about two thousand years, and every later step was an argument with them.
Engineers of Philip II of Macedon (attributed)Macedonia and Athens, Greece
Greek engineers switched from bow-like catapults to torsion catapults, powered by tightly twisted bundles of sinew. An Athenian arsenal list from 338–326 BCE mentions 'springs of sinews'.
Why it mattered. People were storing energy in springs for war two thousand years before anyone wrote down how springs behave.
The Problems, a work attributed to Aristotle or his school, asks why sunlight through a square gap makes a round spot, and why a partial solar eclipse throws crescent-shaped spots through gaps in leaves.
Why it mattered. An early record that small openings project the shape of the light source, not the shape of the hole.
A marble counting board about 1.5 m long, found on the island of Salamis in 1846, is the oldest counting board known to survive. Pebbles on its ruled lines stood for units, tens, hundreds and more.
Why it mattered. It shows that adding by moving counters between columns was everyday work more than 2,000 years ago.
Texts attributed to Charaka; later Ayurvedic writersIndia
Ayurvedic texts describe a condition with tremor, stiffness and slow movement, later called kampavata, and treat it with seeds of kapikacchu (Mucuna pruriens). In 1937 Indian chemists found L-dopa in those seeds, the same drug doctors now use for Parkinson’s disease.
Why it mattered. An old remedy turned out to contain the medicine that replaces missing dopamine.
compiled over centuries, c. 1st millennium BCE to early centuries CE (dates debated) · No. 039 KidneyClear
Cutting out bladder stones
Sushruta and the Sushruta SamhitaAncient India (traditionally Varanasi)
The Sushruta Samhita, a Sanskrit surgical text built up over several centuries, describes how to remove a stone from the bladder through a cut in the perineum, with the patient held in position. It lists stones among the hardest diseases to treat.
Why it mattered. It is one of the oldest detailed descriptions of stone surgery, a problem people have fought for thousands of years.
Herophilus, one of the first scientists to dissect human bodies, described a gland lying along the start of the intestine. Aristotle had already used the word pancreas for something in animals, but Herophilus is usually credited with the first description.
Why it mattered. It put the pancreas on the anatomical map, though its jobs would stay a mystery for 2,000 years.
Theophrastus, a student of Aristotle, wrote a short work, On Odours, about scents, perfumes and how they are made and kept. He noted that smells are hard to name and classify, a problem scientists still wrestle with.
Why it mattered. It is one of the earliest attempts to write down what smells are and how they work.
The Sushruta Samhita, an ancient Indian surgical text whose date scholars still debate, describes ways to rebuild torn earlobes using flaps of nearby skin. Stretched, heavy earrings often tore them.
Why it mattered. It shows skilled ear surgery in India long before anyone understood how hearing works.
Euclid's Optics treats vision with straight lines drawn from the eye to what it sees. Like many Greek thinkers he imagined the rays going out of the eye, not in.
Why it mattered. His geometry of straight rays survived, even though the direction turned out to be backwards.
Working in Alexandria, two Greek doctors dissected human bodies. Herophilus told nerves apart from tendons and traced them to the brain and spinal cord, and he and Erasistratus separated nerves for feeling from nerves for movement.
Why it mattered. For the first time nerves were seen as the body’s own wiring, rooted in the brain.
Erasistratus dissected bodies in Alexandria and traced nerves into muscles. He thought a muscle shortened because it swelled with pneuma sent down the nerves, getting fatter as it got shorter.
Why it mattered. The "inflation" idea lasted for almost 2,000 years until experiments disproved it.
Ashoka’s second rock edict says he arranged medical care for people and for animals, and had medicinal herbs, roots and fruit planted and brought in where they did not grow.
Why it mattered. It is one of the earliest records of a state providing medical care.
In On the Equilibrium of Planes, Archimedes proved that weights balance on a lever when weight × distance from the pivot is the same on both sides. It is the principle of moments, the rule every seesaw obeys.
Why it mattered. The first exact law of torque, over 2,000 years before the word existed.
In On Floating Bodies, Archimedes proved that a body in a fluid is pushed up by the weight of the fluid it displaces. A body lighter than the same volume of fluid floats, sinking until it has displaced its own weight. He even worked out when floating shapes like a ship's hull stay upright.
Why it mattered. It is the principle every ship designer, balloonist and submarine commander still uses.
In On the Equilibrium of Planes, Archimedes proved that weights balance on a lever when weight times distance from the pivot is the same on both sides. A later writer, Pappus, credits him with the boast: give me a place to stand and I will move the Earth.
Why it mattered. It is the first exact rule for trading a small force for a big one.
In his book On Floating Bodies, Archimedes worked out that a body in water is pushed up by a force equal to the weight of the water it pushes aside. He treated water as something that presses on whatever is in it.
Why it mattered. It was the first mathematical treatment of fluids at rest, the starting point for everything Pascal later did.
Ctesibius built the hydraulis, a water organ. Hand pumps pushed air into a tank where water kept the pressure steady, and pressing a key let the air blow through a pipe. It is the earliest known keyboard instrument.
Why it mattered. The idea of a row of keys, one for each note, started here, almost 2,000 years before the piano.
The Sushruta Samhita, a Sanskrit text on medicine and surgery, describes more than a hundred instruments, the removal of cataracts and the rebuilding of a nose with a flap of skin from the cheek. Scholars date the text over several centuries around the turn of the era.
Why it mattered. Its nose reconstruction was copied by British surgeons in 1794 and helped start modern plastic surgery.
Authors of the Charaka and Sushruta SamhitasAncient India
The great Ayurveda texts of ancient India were written and edited over several centuries, so their dates are uncertain. They describe prana, the vital air, moving through channels called pranavaha srotas, with roots in the heart. They also name breathing troubles such as shvasa (breathlessness) and kasa (cough).
Why it mattered. Long before anyone knew about oxygen, people saw that breath and life go together.
In his farming book De Agri Cultura, Cato wrote a recipe for globi: balls of cheese and spelt dropped into hot lard in a copper pan, turned with two sticks, then spread with honey and poppy seeds. Frying in olive oil was already known in Greece, and the later Roman cookbook Apicius has fried dishes too.
Why it mattered. It is one of the oldest written frying recipes we can still cook today.
Buddhist sculptorsBhaja Caves, near Pune, Maharashtra
The Bhaja Caves are rock-cut Buddhist caves from about the 2nd century BCE. One carving shows a woman playing a pair of drums while another person dances. Some researchers, including the tabla player Aban Mistry, have pointed to it as a very early tabla-like pair, though it is not a tabla as we know it.
Why it mattered. It shows that playing two drums side by side is a very old idea in India.
The oldest Chinese fans that still exist are a pair of side-mounted fans woven from bamboo, from the 2nd century BCE. The Chinese character for “fan” combines the signs for “door” and “feather”.
Why it mattered. China became one of the great homes of fan making and fan painting.
100 BCE
compiled c. 100 BCE–200 CE; revised by Dridhabala c. 5th–6th century CE · No. 080 AyurvedaClear
The Charaka Samhita
Attributed to Charaka, after Agnivesha; completed by DridhabalaNorth-west India
The great text of internal medicine: 120 chapters on the three doshas, diet, diagnosis, medicines and the qualities of a good physician. It was compiled in layers, and the version we read today includes a later revision.
Why it mattered. It set out the ideas that Ayurveda still teaches, from tridosha to prakriti.
The Charaka Samhita, a founding text of Ayurveda compiled over several centuries, pictures digestion as the work of agni, a fire inside the body. Its main fire, jatharagni, burns in the belly and turns food into the body’s tissues.
Why it mattered. It is one of the oldest ideas of digestion as a process that transforms food, not just a place where food sits.
Etruscan haruspices (liver readers)Found near Piacenza, Italy
A life-sized bronze sheep's liver, found by a farmer in 1877, is covered in the names of Etruscan gods. Each region of the liver belonged to a god, so a mark in that spot was a message from them. Etruscan liver readers were so famous that Romans hired them.
Why it mattered. It shows how the idea of reading livers spread from Mesopotamia across the ancient world.
The Charaka Samhita, a founding text of Ayurveda put together over several centuries, pictures digestion as the work of agni, a fire inside the body. Its main fire, jatharagni, burns in the belly and is said to rule all the others.
Why it mattered. Digestion as heat that transforms food became one of the oldest and longest-lasting ideas about the stomach.
The Charaka Samhita (compiled by physicians in the tradition of Agnivesha and Charaka)Ancient India
The Charaka Samhita, a founding text of Ayurveda, describes six rasas, or tastes: madhura (sweet), amla (sour), lavana (salty), katu (pungent), tikta (bitter) and kashaya (astringent). A healthy diet, it says, balances all six. Its date is uncertain; it was revised over several centuries.
Why it mattered. Its six tastes include pungent and astringent, which science now files under touch and pain rather than taste, as this box shows.
The Yellow Emperor’s Inner Classic is a founding text of Chinese medicine. Historians date its parts to between the Warring States period and the Han dynasty. In this tradition the lung governs qi: it breathes in clear qi from nature and breathes out stale qi from the body.
Why it mattered. It pictured the lungs as an exchange between the body and the outside air, which is close to the truth.
Families in Han China were buried with small clay models of the things they used every day, including kitchen stoves. Many models show a closed firebox with holes on top for pots and a short chimney at the back, sometimes shaped like a dragon.
Why it mattered. Closing in the fire and giving smoke its own pipe is the same idea as a modern hob and duct.
Sergius Orata (attributed)Campania, Roman Republic (today Italy)
Roman baths were warmed by a hypocaust: a furnace pushed hot gases through a hollow space under a raised floor and up through the walls. The writer Vitruvius credited the businessman Sergius Orata with the idea, though some think it is older. Orata became famous for his heated ‘hanging baths’.
Why it mattered. Burning fuel to heat water and rooms in one system is the idea behind every gas and oil water heater.
In his long poem On the Nature of Things, the Roman poet Lucretius explained smells, like tastes, with tiny atoms. Pleasant smells, he wrote, come from smooth, round atoms, and harsh ones from rough, hooked atoms that scrape the nose.
Why it mattered. The idea that a smell depends on the shape of its particles comes back, in a new form, 2,000 years later.
In his book on architecture, Vitruvius described three bronze vessels over a bath furnace: one for hot water, one for warm and one for cold. When hot water was drawn off, warm water flowed in to replace it, and cold water refilled the warm.
Why it mattered. Feeding cold water in as hot water goes out, without mixing the two too much, is still how a storage geyser works.
About 200 years after Archimedes, the Roman architect Vitruvius told how King Hiero suspected his new gold crown had silver mixed in. Archimedes noticed the water rising as he got into his bath, ran home shouting 'Eureka!' ('I have found it') and compared the water the crown and pure gold pushed aside. Historians treat the bath story as a legend.
Why it mattered. Legend or not, it shows the idea: silver makes the same mass bigger, so it displaces more water.
A surgical text of 186 chapters. It describes over a hundred instruments, has students practise cuts on gourds and dead animals, and gives the first written account of rebuilding a nose with a flap of skin from the cheek.
Why it mattered. Its rhinoplasty method is still recognised in the history of plastic surgery.
The sage Svati, in a story told in the Natya Shastra (attributed to Bharata)India
The Natya Shastra is an ancient Sanskrit guide to drama, dance and music. It tells how the sage Svati heard heavy rain drumming on lotus leaves and noticed high, middle and low sounds. The story says this gave him the idea for the first drums, which the text calls pushkaras.
Why it mattered. It is one of the oldest stories anywhere about where the sound of a drum comes from.
The Natya Shastra is an ancient Sanskrit guide to drama, dance and music. It discusses the bamboo flute, called vamsha or venu, among the instruments of the stage. Scholars disagree about its date, but most place it somewhere between about 200 BCE and 200 CE.
Why it mattered. It shows the bamboo flute was already a serious instrument in Indian music around 2,000 years ago.
The Natya Shastra describes the pushkara drums in detail: their sizes, the woods and hides to use, and a blackish earth from riverbanks for the drum. It also mentions pastes put on the drum skins to sweeten the sound. Scholars date the text to somewhere between about 200 BCE and 200 CE.
Why it mattered. It is the earliest written hint of the idea behind the tabla's black spot: putting something heavy on a drum skin to make it musical.
Hero's Mechanics lists five devices for moving heavy loads: the lever, the windlass, the pulley, the wedge and the screw. He explained them with balanced forces, but had no idea yet of work.
Why it mattered. These are still the simple machines taught in school today.
Wang Chong (describing a 'south-pointer')Han dynasty
Wang Chong's book Lunheng mentions a 'south-pointer' that comes to rest pointing south. Many historians read it as a lodestone spoon spun on a bronze plate, used for divination rather than travel. Others doubt such a spoon ever existed.
Why it mattered. If the reading is right, it is the first known magnetic direction-finder.
The Greek physician Rufus, in a book on naming the parts of the body, called the gland pan-kreas, 'all flesh', because it seemed to be soft flesh with no bone or cartilage. The name stuck.
Why it mattered. We still use his word, in almost every language.
Cai Lun, an official of the Han court, is credited with improving and standardising papermaking from bark, hemp, rags and old fishing nets. Paper spread along the Silk Road to the Islamic world and, much later, to Europe.
Why it mattered. Pens are only half the story: cheap paper made writing an everyday act.
The Greek doctor Aretaeus gave a vivid description of diabetes, from the Greek for 'passing through' like a siphon: great thirst, huge amounts of urine, and a body that wastes away. He did not know its cause.
Why it mattered. His words gave the disease its lasting name and picture.
Poets of the Sangam ageTamilakam (today Tamil Nadu and Kerala)
Old Tamil poems from the Sangam age describe the flute, called kuzhal, as the most popular wind instrument of its time. One poem, the Perumpanarruppadai, describes how a flute was made, with holes burned into bamboo using red-hot embers. The exact dates of these poems are still debated.
Why it mattered. It is one of the earliest descriptions anywhere of how a flute was actually made.
In Book V of his Optics, Ptolemy measured how much a ray of light turns when it passes from air into water, from air into glass and from water into glass. He set the angles out in tables, every 10 degrees. His numbers follow a neat pattern that historians think he partly smoothed to fit his own rule.
Why it mattered. It was the first careful attempt to measure refraction, and his tables were copied for over a thousand years.
Galen, a Greek doctor working in Rome, joined the four humours to the qualities hot, cold, moist and dry and wrote hundreds of works. His ideas ruled medicine in Europe and the Islamic world for over a thousand years.
Why it mattered. Galen’s temperaments became Unani’s mizaj.
Galen, doctor to Roman gladiators and emperors, wrote "On the Movement of Muscles". He showed that muscles act only by pulling, that they work in opposing pairs, and that cutting a nerve paralyses the muscle it serves.
Why it mattered. The idea of antagonist pairs, like the biceps and triceps, starts with him.
Galen wrote a short book, On Bones for Beginners, to teach students the skeleton first. He told them to go to Alexandria and look at a real human skeleton with their own eyes. But most of his own dissections were on apes, so some of his details were wrong for humans.
Why it mattered. His bone book was followed for well over a thousand years, mistakes and all.
Galen cut the small nerves that run beside a squealing pig’s windpipe, and the pig fell silent though it still struggled. He also showed that cutting the spinal cord at different levels paralysed the body below the cut. He thought nerves were hollow tubes carrying “animal spirits”.
Why it mattered. He proved that the brain controls the body through nerves, a view that lasted 1,500 years.
Galen, a Greek doctor in the Roman Empire, taught that the stomach “concocts” food like a cooking pot, and that the liver turns what it absorbs into blood. His books guided medicine for well over a thousand years.
Why it mattered. It linked the gut and the liver, but as cooking rather than chemistry.
The Greek doctor Galen cut open a live pig in front of an audience in Rome. When he cut two thin nerves in its neck, the pig went silent, though it still struggled. He had shown that the voice is made in the larynx, the voice box at the top of the windpipe, and that nerves from the brain control it.
Why it mattered. It was one of the first experiments to show that nerves, not the heart, run the parts we breathe and speak with.
Galen, a Greek doctor in the Roman Empire, taught that the liver makes blood from food and the veins carry it out to be used up. He thought blood seeped from the right side of the heart to the left through tiny invisible pores. His books were followed for well over a thousand years.
Why it mattered. It was a one-way model, not a loop, and it took centuries to overturn.
Galen, a Greek doctor working in Rome, taught that every body is a mixture of hot, cold, wet and dry. In his book Mixtures he trained doctors to judge that mixture partly by touch, using their own skin as the measuring tool. His ideas guided medicine for well over a thousand years.
Why it mattered. It treated skin as a sensing instrument, long before anyone knew how skin senses anything.
Some doctors of his day said urine simply seeped into the bladder. In On the Natural Faculties, Galen describes tying off the ureters of a living animal: the bladder stayed empty while the ureters above the knot swelled with urine.
Why it mattered. It was an early experiment showing that urine is made in the kidneys and carried down the ureters.
Galen taught that digested food travels up the portal vein to the liver, where it is turned into blood. The veins then carried that blood out to the body to be used up. Doctors followed his books for more than a thousand years.
Why it mattered. He was right that food goes straight to the liver, even though the liver does not make blood in adults.
Galen, a Greek doctor in the Roman Empire, taught that food is 'concocted', a kind of cooking, in the stomach into a juice called chyle. He said veins in the gut wall soak up the chyle and the portal vein carries it to the liver, which turns it into blood. His books were followed for well over a thousand years.
Why it mattered. He was right that the gut's blood goes straight to the liver, and his model shaped every later question about digestion.
Galen taught that the stomach draws food in, holds it and cooks it with the body’s own heat into a juice, a process called concoction, before pushing it on. The juice was thought to go to the liver to be made into blood. His books were followed for well over a thousand years.
Why it mattered. The idea of the stomach as a warm cooking pot shaped medicine until experiments in the 1700s.
Galen described a nerve running from the hard, stony part of the skull into the brain and taught that it carried sound. He worked mostly from animal dissections and knew nothing of the tiny ear bones.
Why it mattered. For over a thousand years, doctors learned about hearing from his books.
The physician Galen showed in public experiments that cutting certain nerves in the neck silenced a pig’s squeal while it kept breathing. He argued that the brain, through the nerves, controls the voice and the muscles.
Why it mattered. His ideas, right and wrong, guided medicine for about 1,400 years.
The Greek doctor Galen taught that we breathe to cool the heat of the heart and to draw in pneuma, a kind of life spirit carried by the air. Earlier, around 250 BCE, Erasistratus in Alexandria had said that pneuma travels from the lungs into the heart and arteries.
Why it mattered. Galen’s ideas ruled medicine in Europe and the Islamic world for well over a thousand years.
Galen, a Greek doctor working in the Roman Empire, taught that blood is made in the liver and carried out by the veins to be used up. He said some blood seeped from the right side of the heart to the left through tiny, invisible pores in the wall between them. His books were followed for well over a thousand years.
Why it mattered. His model was so trusted that it took centuries of careful looking to prove the heart is really a pump in a loop.
Chinese records credit the Han dynasty craftsman Ding Huan with a rotary fan of seven wheels, each about 3 m across, turned by hand to cool a hall. Sources disagree on when he lived. Centuries later, in 747, a Tang emperor's Cool Hall is said to have used water-powered fan wheels and fountains.
Why it mattered. Moving air across skin helps sweat evaporate, the oldest way to feel cooler.
Ding Huan (attributed)Chang'an (near today's Xi'an), China
Later accounts credit the Han craftsman Ding Huan with a hand-cranked rotary fan: seven wheels about 3 metres across that one person could turn to cool a whole hall. Historians are not sure of the exact date, and the story comes from later records.
Why it mattered. It is the earliest known record of a fan that spins instead of waves.
A book credited to Xu Yue is thought to be the earliest written description of the suanpan, the Chinese bead abacus, though scholars debate exactly what it describes. By the Ming dynasty the suanpan, with 2 beads above the bar and 5 below, was used across China, and trained users could add faster than early mechanical calculators.
Why it mattered. A bead frame keeps a number as positions in columns and adds by carrying from one column to the next, just like the adder in this box.
This Sanskrit medical text advises boiling water, warming it in the sun and filtering it through sand and coarse gravel. Old books often say it dates from 2000 BCE, but scholars now think it was put together over several centuries and finished around the 3rd or 4th century CE. In India the seeds of the clearing-nut tree (nirmali or kataka) have long been rubbed in water pots to make mud settle.
Why it mattered. It shows people in India were already treating drinking water with heat, sunlight and sand, long before anyone knew about germs.
The Chinese doctor and alchemist Ge Hong collected handy remedies in a book of emergency recipes. Among them was seaweed soaked in wine to shrink goitres. Nobody knew why it worked.
Why it mattered. Seaweed is full of iodine, the very thing the thyroid needs to make its hormones.
Pappus of Alexandria, quoting ArchimedesAlexandria
Pappus's Collection records the boast attributed to Archimedes: give me a place to stand and I will move the Earth. With a long enough lever arm, a small force makes any torque you like.
Why it mattered. The most famous line in physics is a statement about lever arms.
Synesius of Cyrene, writing to HypatiaCyrene and Alexandria
In a letter, the bishop Synesius asked his teacher Hypatia of Alexandria to have a 'hydroscope' cast in brass: a notched tube with a weighted cone that sinks more or less deeply depending on the liquid. It is one of the earliest descriptions of a hydrometer. Some later writers credit Hypatia with inventing it, but the letter only shows she was asked to have one made.
Why it mattered. A floating tube that reads a liquid's density is still how milk, batteries and wines are tested.
Nalanda grew into a great Buddhist centre of learning from about the 5th century. Visiting Chinese monks, among them Yijing in the 7th century, wrote about the medicine they saw practised in India; medicine was one of the subjects studied, though the details are uncertain.
Why it mattered. Monasteries helped carry Indian medicine along the Silk Road to Central Asia, Tibet and China.
The Thirukkural, a much-loved book of Tamil couplets, has a chapter called Marunthu (medicine). Couplet 941 says that the three things counted by the learned, beginning with vatham (wind), cause disease when they are too much or too little.
Why it mattered. It shows the idea of three humours in Tamil writing long before Siddha had a separate name.
Found by Lt Hamilton Bower; read by Rudolf HoernleKucha, Xinjiang
Birch-bark pages buried in a Buddhist stupa on the Silk Road hold Sanskrit medical texts, including a manual called the Navanitaka and a treatise on garlic. Hoernle, working in Calcutta, deciphered them between 1893 and 1912.
Why it mattered. It is among the oldest surviving physical manuscripts of Indian medicine.
In his commentary on Aristotle's Physics, Philoponus said air cannot keep a thrown stone moving. Instead, the thrower gives the stone a force of its own. He also said that if you drop a heavy and a light weight together, they land at almost the same time.
Why it mattered. It was the first clear break with Aristotle's idea that air does the pushing.
The Alexandrian scholar John Philoponus wrote that if you drop two weights, one many times heavier, the difference in their fall times is very small. He argued that moving things carry an 'impetus' given to them.
Why it mattered. It was the first recorded doubt, based on dropping things, that heavier means faster.
Aristotle had said the air keeps a thrown stone moving. Philoponus disagreed: the thrower gives the stone an inner 'impressed force' that slowly wears away. It was the first hint that motion is something a body carries with it.
Why it mattered. It moved the cause of motion from the air into the moving thing itself.
Philoponus attacked Aristotle's air-pushing idea. He argued that the thrower gives the stone an inner 'impressed force' that carries it on and slowly wears away, and that a stone would move even through empty space.
Why it mattered. It moved the cause of motion from the air into the moving object itself.
In the Vaisheshika school of Indian philosophy, Prashastapada described a quality called samskara. One kind, vega, keeps a moving thing moving until other forces wear it down. Another, sthitisthapaka, is the springiness that pulls a bent thing back into shape.
Why it mattered. It shows that thinkers in India were puzzling over inertia and elasticity many centuries before Europe.
Vagbhata combined the teachings of Charaka and Sushruta into one clear text in verse, organised around the eight branches. It became the main textbook in Kerala and was translated into Tibetan.
Why it mattered. It is still one of the most studied Ayurvedic texts today.
Flight feathers, usually from geese, became Europe's main writing tool. The hollow shaft held a small drop of ink, and a penknife recut the point as it wore down. Isidore of Seville mentions quills in the early 600s.
Why it mattered. The quill wrote most of Europe's books, letters and laws for over a thousand years. The word “pen” comes from the Latin penna, feather.
In his Brāhmasphuṭasiddhānta, Brahmagupta gave rules for adding, subtracting and multiplying with zero and negative numbers. Indian mathematicians worked sums on dust boards (pāṭī) using the place-value digits 0 to 9, and India also knew counting boards, though how widely they were used is debated.
Why it mattered. The decimal place-value system with zero, which travelled from India to the world, is what every calculator displays.
Aryabhata and BrahmaguptaKusumapura and Bhillamala, India
In 499 Aryabhata described a round Earth that spins, hanging in space. In 628 Brahmagupta wrote, as later quoted by al-Biruni, that all heavy things fall to the Earth because it is the nature of the Earth to attract and keep them, just as it is the nature of water to flow. It was an idea in words, not yet a law with numbers.
Why it mattered. It is one of the earliest clear statements that falling is caused by the Earth pulling on things.
The Thirumandiram, some 3,000 verses attributed to the sage Thirumoolar, is the earliest known Tamil treatise on yoga and teaches care of the body as a path to the spirit. Scholars date it anywhere from the 5th to the 8th century, and tradition claims far earlier.
Why it mattered. Siddhas count Thirumoolar among the 18 Siddhars, and his view of the body shaped the tradition.
The Byzantine physician Theophilus wrote De Urinis, often called the first text devoted only to urine. It taught doctors to judge illness by its colour, cloudiness and sediment.
Why it mattered. It set the pattern of medieval uroscopy for centuries.
The Madhava Nidana gathered the signs and causes of diseases, chapter by chapter, into one book on diagnosis (nidana). Later physicians used it as the standard reference.
Why it mattered. It made diagnosis a subject of its own in Ayurveda.
During the Tang dynasty, Chinese engineers used water power to turn fan wheels for cooling. Rotary fans became even more common under the Song dynasty.
Why it mattered. Letting water do the work was the first step towards fans that turn by themselves.
At the Abbasid court, the Sushruta Samhita was translated into Arabic as the Kitab Shah Shun al-Hindi, and Charaka’s text was translated too. Indian physicians worked in Baghdad’s hospitals.
Why it mattered. Indian medicine fed into the Greek-Arabic tradition that became Unani medicine (see UnaniClear).
Scholars of the Abbasid caliphs, especially under al-Ma’mun (r. 813–833)Baghdad
Baghdad became a centre of translation where Greek, Persian and Indian books were put into Arabic. The House of Wisdom is the name linked to this effort, though historians debate how big an institution it was.
Why it mattered. It carried Greek medicine into Arabic, where it grew.
The Arab scholar al-Kindi is credited with a Book of the Chemistry of Perfume and Distillations, with over a hundred recipes for scented oils, salves and waters, and the methods to make them.
Why it mattered. It records perfume-making as careful chemistry, with written recipes others could repeat.
After 711, Arab and Berber rulers brought the oud, a round-backed lute, to al-Andalus in Spain. The musician Ziryab (789–857) is said to have added a fifth string to his oud and founded a music school there. Spain became one of the doors through which the lute entered Europe.
Why it mattered. The guitar grew up in Spain, alongside the lute family that the oud brought there.
Wang Jie (who paid for it) and unknown block cuttersDunhuang, China
The Diamond Sutra is a scroll printed from carved wooden blocks. It carries a date equal to 11 May 868, which makes it the oldest dated printed book known. A whole page was carved into one block, inked and pressed onto paper.
Why it mattered. It shows the core idea every printer still uses: ink put down in a pattern, the same way, copy after copy.
Agathiyar, Bogar, Theraiyar, Thirumoolar and othersTamil country
Tradition honours 18 Siddhars, sages remembered as masters of yoga, alchemy and healing, with Agathiyar (Agastya) as the founder. Lists of names differ, and so do the dates given for them. Many texts are attributed to them, such as nei kuri, the urine oil-drop test, to Theraiyar.
Why it mattered. The Siddhars give the system its name and its authority.
Al-Razi ran hospitals and kept detailed case notes, collected after his death as al-Hawi, a huge medical encyclopedia. He also questioned some of Galen’s claims when they did not match what he saw.
Why it mattered. He showed that experience can correct the old books.
The Persian physician al-Razi wrote a treatise on stones in the kidney and bladder, describing their symptoms, how they differ, and how to treat them. His works were later translated into Latin and read in Europe for centuries.
Why it mattered. It set out kidney stones as a disease to be studied carefully, not just endured.
The Bhagavata Purana, most likely written down between about 800 and 1000 CE, tells how the cowherd god Krishna played his flute in the forests of Vrindavan. The music was so beautiful that the gopis, the cowherd women, left their homes to follow it. Krishna the flute player, often called Venugopala, became one of the best-loved images in Indian art.
Why it mattered. Krishna's flute made the bamboo bansuri a sacred instrument that millions of people know by heart.
Al-Razi describes treating one group of patients with brain inflammation by bloodletting and deliberately leaving another group untreated, then comparing them.
Why it mattered. An early seed of the controlled trial (see the evidence chapter).
The Fatimid caliph asked for a pen that wouldn't stain his hands or clothes. According to his chronicler, Qadi al-Nu'man, he was given a pen that carried ink in a reservoir and let it out only when used for writing.
Why it mattered. It is the earliest known record of what we'd now call a fountain pen.
Abu Sa'd al-'Ala' ibn SahlBaghdad, Abbasid Caliphate
In a book called On Burning Mirrors and Lenses, Ibn Sahl used the correct law of refraction to design lenses that focus sunlight to a single point. The book survived only in scattered pieces in libraries in Damascus and Tehran. In 1990 the historian Roshdi Rashed put it back together and showed that Ibn Sahl had the law.
Why it mattered. The law we call Snell's was first used in Baghdad, more than six centuries before Snell.
The folding fan was invented in Japan, probably between the 6th and 9th centuries. In 988 the Japanese monk Chōnen sent gifts to the Song emperor that included twenty fans of thin cypress slats and two folding paper fans.
Why it mattered. A fan that folds flat could go anywhere, and it spread from Japan to China and later to the world.
Abu al-Qasim al-Zahrawi (Albucasis)Córdoba, al-Andalus
Al-Zahrawi wrote a 30-part medical encyclopedia, the Kitab al-Tasrif. Its last part, on surgery, has a whole section on fractures and dislocations, with drawings of tools. A way to put back a dislocated shoulder that is now named after a 19th-century Swiss surgeon appears in it centuries earlier.
Why it mattered. Translated into Latin, it became a standard surgery book in Europe for about 500 years.
Byzantine and German musiciansByzantine Empire to German lands
Side-blown flutes seem to have reached Europe from Asia through the Byzantine Empire, and then spread to German-speaking lands and France. That is probably why Europeans long called it the German flute. The exact route and dates are uncertain because few early flutes survive.
Why it mattered. It brought the transverse flute into the music that would later grow into the orchestra.
In his Book of Optics, written in Cairo, Ibn al-Haytham argued with experiments that we see because light from objects enters the eye, not because the eye sends out rays. He studied the anatomy of the eye and the camera obscura.
Why it mattered. It set optics on the path of testing ideas with experiments, and shaped European science for centuries.
Ibn Sina is often credited with improving steam distillation to capture the essential oil of roses, though rose water was being distilled before him. Rose water and rose oil became famous trade goods across the Islamic world and beyond.
Why it mattered. Distillation let perfumers capture a flower’s smell molecules in a bottle.
In his Book of Healing, Ibn Sina argued that a thrown body receives an inclination (mayl) that would last forever in empty space; only the air's resistance uses it up. It is close to the modern idea that motion needs no push to continue.
Why it mattered. He imagined motion that never runs down, centuries before Galileo and Newton.
In The Book of Healing, Ibn Sina described an inclination given to a projectile that is used up only by the resistance of the air. In a vacuum, he reasoned, nothing would use it up, so the motion would not stop.
Why it mattered. It was one of the first statements that only resistance makes moving things stop.
In The Book of Healing, Ibn Sina described a 'mayl', an inclination given to a thrown object. He argued that it is used up only by things like air resistance, so in a vacuum a moving object would never stop.
Why it mattered. It came remarkably close to the idea of inertia, six centuries before Galileo.
In his Book of Optics, Ibn al-Haytham built a brass instrument to measure rays passing into water and glass. He explained that light bends because it moves more easily in one material than another, and studied how the eye and lenses use refraction. He came close to the exact law but did not state it.
Why it mattered. His book, translated into Latin, taught European scientists to test ideas about light with experiments.
In his Book of Optics, Ibn al-Haytham describes placing several candles outside a darkened room and seeing a separate image of each flame through the opening. Cover a candle and only its image disappears. He also argued, correctly, that we see because light enters the eye, not because the eye sends out rays.
Why it mattered. He turned the pinhole effect into a controlled experiment, and his Book of Optics shaped optics in Europe for centuries.
Ibn Sina finished al-Qanun fi al-Tibb, five books covering the humours and temperaments, diseases, and hundreds of medicines. It also set out rules for testing whether a medicine works, and described some diseases as passing between people.
Why it mattered. It became the core text of Unani, still studied by hakims today.
Al-Biruni built a conical flask with a spout near the top. Dropping a gem or metal in made water overflow, and weighing the overflow gave the object's volume. With it he listed the specific gravities of metals and precious stones with remarkable accuracy.
Why it mattered. It turned Archimedes' idea into a careful laboratory method for identifying materials.
Bi Sheng made separate characters from baked clay that could be arranged into a page, printed, then taken apart and reused. We know about him from the writer Shen Kuo. His type was not widely used, but the idea was new.
Why it mattered. Reusable pieces that make up any page are the ancestors of the dots a modern printer arranges.
In his Dream Pool Essays, Shen Kuo describes rubbing a needle on lodestone and hanging it from a single silk thread so it points south. He also noted that it does not point exactly south, but a little to the east: the first record of magnetic declination.
Why it mattered. It is the earliest clear description of a compass needle, and of the gap between magnetic and true north.
Ink made from oak galls and iron salts turns from pale to deep black as it reacts with air, and bites into parchment so it can't be scraped off. It was the standard ink for centuries.
Why it mattered. Many of the most important documents in Western history are written in it, but its acidity slowly eats the page.
Zhu Yu's Pingzhou Table Talks, written in 1117 about the years around 1100, says that ship pilots steered by the stars at night and the Sun by day, and in dark weather looked at the south-pointing needle. The compass reached Europe and the Islamic world within about a century.
Why it mattered. It is the first written record of a compass used for navigation at sea.
Al-Khazini described a large hydrostatic balance and tables of the specific gravities of about fifty metals, stones and liquids, building on al-Biruni's work. His value for gold, about 19.05, is close to today's 19.3.
Why it mattered. It was the most complete book on weighing in water for centuries.
Gerard translated the Canon from Arabic into Latin in Toledo, a meeting point of Arabic and European learning. Printed Latin editions later spread it across Europe.
Why it mattered. Europe’s doctors now learned medicine partly from Ibn Sina.
Castle buildersConisbrough Castle, Yorkshire, England
Chimneys were invented in northern Europe in about the 11th or 12th century. The earliest known one in England is at Conisbrough Castle, built around 1185. Chimneys were costly, so most ordinary homes did not have one until the 1500s and 1600s.
Why it mattered. A chimney uses a tall column of warm air to pull smoke out of the room, which is exactly what a kitchen chimney's duct does.
Gilles de Corbeil and the Salerno schoolSalerno, Italy, and Paris, France
Gilles de Corbeil wrote a teaching poem linking about twenty kinds of urine to illnesses. The matula, a bladder-shaped glass flask, became the symbol of physicians in paintings for centuries.
Why it mattered. People already sensed that urine reports on the body, even if they read it wrongly.
With the Delhi Sultanate from the 13th century, Persian- and Arabic-speaking hakims settled in India. Their medicine became known as Unani Tibb, “Greek medicine”.
Why it mattered. It began Unani’s long home in South Asia.
Jordanus described 'positional gravity': a weight pulls harder or softer on a lever depending on its position and the direction it can move. He proved the law of the lever from the idea of work and solved weights on slopes.
Why it mattered. He began turning Archimedes' balance into a theory of forces at angles.
Writing a commentary on the Canon, Ibn al-Nafis said blood must pass through the lungs to get from the right side of the heart to the left, correcting Galen.
Why it mattered. Doctors in this tradition could and did correct their masters.
Galen had said blood seeps through tiny holes in the wall of the heart. The Damascus-born doctor Ibn al-Nafis said that was wrong: blood travels from the right side of the heart to the lungs, mixes with air, and comes back to the left side. Europe did not know his book until a copy was found in Berlin in 1924.
Why it mattered. It is widely credited as the first correct description of blood picking up air in the lungs.
In a commentary on Avicenna's Canon, the Damascus-born doctor Ibn al-Nafis said there are no pores in the heart's middle wall. Blood from the right side must travel through the lungs, mix with air, and return to the left side. Europe only learned of his work in the 20th century.
Why it mattered. It is the first known correct description of the pulmonary loop.
In his Commentary on Anatomy in Avicenna’s Canon, the Damascus-born doctor Ibn al-Nafis said Galen was wrong: blood cannot pass through tiny holes in the wall of the heart. Instead it travels from the right side of the heart to the lungs, mixes with air, and returns to the left side. Europe did not know his work; a copy was found in a Berlin library in 1924.
Why it mattered. It is widely credited as the first correct description of the pulmonary circulation, about 300 years before Europeans described it.
In his Commentary on Anatomy in Avicenna's Canon, usually dated to about 1242, the Damascus-born doctor Ibn al-Nafis said there are no pores in the heart's middle wall. Instead, blood from the right side must travel through the lungs, mix with air, and come back to the left side. Europe did not learn of his work until the 20th century.
Why it mattered. It is the first known correct description of the lung loop, the pulmonary circulation.
Petrus Peregrinus de MaricourtSiege of Lucera, Italy
In a letter written during a siege, the French scholar Peter Peregrinus named the two ends of a magnet its poles, showed that like poles repel and unlike attract, and noted that breaking a magnet gives two magnets, each with both poles.
Why it mattered. It was the first careful experimental account of magnets in Europe, and it busts a myth still told today.
The French poet Adenet le Roi mentioned the side-blown flute in a poem written around 1285. It is usually counted as the first literary reference to the transverse flute in western Europe.
Why it mattered. Words in old books help historians track instruments that have rotted away.
Convex lenses in frames, to help older people read, appeared in northern Italy. A sermon given in Florence in 1306 by the friar Giordano da Pisa said the art of making them was not yet twenty years old.
Why it mattered. Spectacles were among the first tools to fix a failing part of the human body, and they gave scholars decades more of reading.
The Sharangadhara Samhita standardised recipes for powders, decoctions and pills, and gave the earliest clear account of nadi pariksha, reading the pulse. Charaka and Sushruta do not describe pulse diagnosis as a method.
Why it mattered. Pulse reading, now seen as typical of Ayurveda, is a later addition.
Medieval doctors across the Islamic world and EuropeEurope and the Middle East
For centuries, looking at urine in a round glass flask called a matula was a doctor's main test. Colour charts linked each shade to an illness. Much of it was guesswork, and by the 1600s critics mocked 'piss prophets'.
Why it mattered. It showed that urine carries clues about the whole body, the idea behind modern urine tests.
A popular story says the poet Amir Khusrau invented the tabla around 1300 by cutting a drum in half. No painting, sculpture or document from his time supports it. Historians think the story may mix him up with a later musician with a similar name.
Why it mattered. It is a good reminder that a story being famous does not make it true.
Thomas Bradwardine, William Heytesbury, Richard Swineshead, John DumbletonMerton College, Oxford, England
A group of Merton College scholars began treating speed as a quantity that can change from instant to instant. Heytesbury's rules of about 1335 include the mean speed rule: speeding up steadily, you cover the same distance as moving the whole time at the speed you had halfway through.
Why it mattered. The mean speed rule is s = ½ (u + v) t, three centuries before Galileo tested it.
Abbot John de Breynton's buildersGlastonbury Abbey, Somerset, England
The Abbot's Kitchen at Glastonbury is an eight-sided stone building with a huge fireplace in each corner. Hot air and smoke rise to an outlet at the top of its pyramid roof, while cooler air comes in lower down. Big medieval kitchens often had a louver like this, a covered roof vent that let smoke out and kept rain off.
Why it mattered. Catching rising smoke high up and giving it a way out is how every cooker hood still works.
Buridan taught that a mover gives a body 'impetus', and that it grows with both the body's quantity of matter and its speed. That is why a heavy iron ball thrown fast goes further than a light one. Only air and gravity wear it down.
Why it mattered. Mass times speed: the recipe for momentum, three hundred years early.
Buridan said a thrown body carries an 'impetus' that stays with it until air resistance and gravity destroy it. The impetus was bigger for more matter and more speed, rather like what we now call momentum. It explained why a heavy millstone is hard to stop once it spins.
Why it mattered. Impetus that doesn't fade on its own is only a short step from inertia.
Buridan said a thrower puts a force called impetus into a stone, and the stone carries it along. Air and weight slowly use it up. He even wondered if it would last for ever with nothing to fight it.
Why it mattered. It moved the push from the air into the moving object, a big step towards inertia.
Nicole Oresme drew a changing speed as a line of heights over time, so that the area of the shape stood for the distance covered. With it he proved the Merton rule with a simple triangle and rectangle.
Why it mattered. It is the first velocity–time graph, and the idea that the area under it is the distance.
Buridan taught that a thrower puts 'impetus' into a stone, and the stone keeps moving until air resistance and weight wear it away. He said more weight and more speed meant more impetus.
Why it mattered. Impetus is a close cousin of what we now call momentum.
Jikji, a Korean Buddhist text, was printed with movable metal type in 1377. It is the oldest surviving book made this way, older than Gutenberg's Bible. The only known copy is in the National Library of France.
Why it mattered. Metal type was stronger and more even than wood or clay.
In 1397 a lawyer in Padua wrote that a man named Hermann Poll claimed to have invented the clavicembalum. In a harpsichord each key lifts a small quill or plectrum that plucks a string. The oldest complete one that survives was made in 1521.
Why it mattered. A plucked note sounds equally loud however hard you press the key, the problem the piano was invented to solve.
The clavichord is first mentioned in a German poem of 1404. Each key pushes a small brass blade called a tangent up against a string, and it stays there while you hold the key. Players could even make the note wobble, but it was so quiet it only suited a small room.
Why it mattered. It let players control loudness with their fingers, but the sound was far too soft for a concert.
Gutenberg combined metal type cast in a hand mould, an oil-based ink and a screw press. His Bible was finished around 1455. Printing spread across Europe within fifty years and books became far cheaper.
Why it mattered. It made printing fast and cheap enough to change how knowledge spread, though every page still had to be set by hand.
From about the 1470s Swiss soldiers used small, shrill side-blown flutes called fifes, with drums, to send signals. As Swiss troops fought across Europe, the instrument spread with them. By the late 1500s flutes were also playing in court and theatre music.
Why it mattered. A loud, simple military flute helped carry the transverse flute into every corner of Europe.
In his notebooks Leonardo sketched blocks pulled across a table by weights hanging over a pulley. He noted that friction grows with the weight pressing down, does not depend on how much of the block touches, and is about a quarter of the weight for smooth surfaces.
Why it mattered. He found the basic laws of friction two centuries early, but his notes stayed unpublished.
Drummers of North Indian courts and templesNorth India
The pakhawaj is a long barrel drum with a skin at each end, played lying on its side. It became the drum of dhrupad, a grand and serious style of singing. Its bass head gets a dab of wheat dough before playing, and its treble head carries a black paste spot, like the south Indian mridangam.
Why it mattered. Many tabla strokes and compositions were first played on the pakhawaj.
In his notebooks Leonardo separated a lever's real arm from its 'potential' arm: the perpendicular from the pivot to the line of the force. Pull at a slant and only that shorter distance counts. Today we call it the lever arm, r sin θ.
Why it mattered. The key to torque for forces at an angle, though his notebooks stayed unpublished for centuries.
Pinder's Epiphanie Medicorum printed a wheel of twenty flasks of different colours, each tied to a diagnosis. Such colour charts were popular in early printed medical books.
Why it mattered. A colour chart for urine returned, this time with evidence behind it, in the 1990s.
Working with an anatomy professor at Pavia, Leonardo dissected human bodies and drew the bones from several sides, like an engineer drawing a machine. His skeleton shows the gentle S-curve of the spine and the slant of the ribs. The drawings were not published, and stayed hidden for centuries.
Why it mattered. They were among the most accurate pictures of the skeleton made up to that time.
Leonardo dissected human bodies and animals and drew what he saw in careful ink drawings. His sheets show the windpipe branching again and again into the bronchi, like the branches of a tree, and the lungs sitting around the heart. Almost all of these drawings are now in the Royal Collection at Windsor Castle.
Why it mattered. They are some of the first accurate pictures of the airways, the path air takes from your throat into your lungs.
The vihuela had a flat, waisted body like a guitar and six pairs of strings, tuned like a lute. In 1536 Luys Milán published El Maestro, the first printed collection of music for it. Players pressed the strings against frets on the neck to pick out each note.
Why it mattered. The guitar shape and the idea of frets for every note were already in place 500 years ago.
Vesalius, a young Flemish anatomy teacher in Padua, dissected human bodies himself instead of reading old books aloud. His De humani corporis fabrica, printed in Basel, showed the body in detailed drawings and corrected hundreds of errors copied for over a thousand years.
Why it mattered. Anatomy, the first foundation of modern medicine, became something you check with your own eyes.
Vesalius published De humani corporis fabrica, a huge anatomy atlas based on his own dissections. Its famous "muscle men" plates peel the body layer by layer and correct many of Galen's errors, which came from animal bodies.
Why it mattered. Muscle anatomy became something you check by looking, not by quoting old books.
Andreas VesaliusPadua, Italy (printed in Basel, Switzerland)
Vesalius, a 28-year-old professor, cut up human bodies himself and published De humani corporis fabrica, with more than 250 woodcut pictures. He showed that Galen had described apes, not people. For example, the human lower jaw is one bone, not two.
Why it mattered. It made careful looking, not old books, the way to learn the skeleton.
Andreas VesaliusPadua, Italy (printed in Basel, Switzerland)
Vesalius, a young Flemish professor, dissected human bodies himself and published a huge illustrated book, De humani corporis fabrica. It showed the stomach, intestines and the rest of the body drawn from real dissections. Where Galen had described animals, Vesalius pointed out the differences in humans.
Why it mattered. It taught doctors to trust what they could see over what old books said.
In his great anatomy book, De humani corporis fabrica, Vesalius described two tiny bones in the middle ear. Their names, malleus (hammer) and incus (anvil), came from their shapes.
Why it mattered. It opened the middle ear to careful study, based on human dissection rather than old books.
Vesalius’s book De humani corporis fabrica showed the brain in detailed woodcuts made from human dissections. He corrected many of Galen’s errors, which had come from studying animals.
Why it mattered. It made careful observation, not old books, the basis of anatomy.
Andreas VesaliusPadua, Italy (printed in Basel, Switzerland)
Vesalius, a young Flemish professor, dissected human bodies himself and published a huge illustrated book, De humani corporis fabrica. He wrote that he could not see Galen's pores in the heart. In the 1555 edition he went further and said no blood passes through that wall at all.
Why it mattered. It taught doctors to trust what they could see over what old books said.
Gemma Frisius used a camera obscura to watch a solar eclipse safely, and in 1545 published a drawing of it: a room with a hole, and the eclipsed Sun projected on the far wall.
Why it mattered. The camera obscura became a scientific instrument, and astronomers kept using it to observe the Sun.
The Sicilian anatomist Ingrassia is usually credited with first describing the third ear bone, the stapes or stirrup, in the 1540s, though his book was only printed after his death. At about 3 mm it is the smallest bone in the body.
Why it mattered. With it, the chain of three bones that carries sound across the middle ear was complete.
The Bhavaprakasha added plants that had recently arrived in India and described phiranga roga, the “Frankish disease” (syphilis), brought by European sailors.
Why it mattered. It shows Ayurveda changing to meet new plants and new diseases.
Servetus, a Spanish doctor and theologian, described blood passing through the lungs inside a book about religion. His ideas were judged heresy, and he and nearly every copy of the book were burned in Geneva in 1553. Only a few copies survived.
Why it mattered. The lung loop was found again in Europe, and almost lost again.
Servetus, a Spanish doctor and theologian, described blood passing through the lungs in a book about religion, Christianismi Restitutio. His religious ideas were judged heresy, and he and nearly every copy of the book were burned in Geneva in 1553. Only a few copies survived.
Why it mattered. It shows the lung loop was found again in Europe, but almost lost for good.
Jesuits, with printer Juan de BustamanteSt Paul's College, Old Goa, India
A press on its way from Portugal to Ethiopia stayed in Goa instead, and printing began at the Jesuit college of St Paul in 1556. Its first known pieces were religious texts. Printing in Indian languages followed over the next decades.
Why it mattered. It began India's own history of print, which leads to today's crowded print shops and home ink tanks.
Della Porta's Magia Naturalis described the camera obscura as a way to entertain guests and help artists draw. Its 1589 edition added a lens and a mirror to turn the image the right way round.
Why it mattered. It made the camera obscura famous across Europe.
Colombo, who had worked with Vesalius in Padua, described the lung loop in his book De re anatomica, published the year he died. He backed it up with dissections and experiments on living animals. William Harvey later gave him credit.
Why it mattered. His book spread the idea of the lung loop among European doctors.
The Italian anatomist Gabriele Falloppio described the two slender tubes that run from the uterus towards the ovaries, with their fringed, trumpet-like ends. His book Observationes Anatomicae was printed in Venice in 1561.
Why it mattered. We still call them fallopian tubes, although nobody then knew that eggs travel along them.
In his Observationes anatomicae, Falloppio described the round and oval windows and the inner ear, and gave us the words cochlea (Latin for snail shell) and labyrinth for its twisting passages.
Why it mattered. The names are still used in every anatomy book and hospital today.
Eustachi's letter on the organ of hearing, dated 1562 and printed in 1564, gave the first detailed post-classical account of the tube joining the middle ear to the throat. It now carries his name: the Eustachian tube.
Why it mattered. It explained how air reaches the middle ear, and why your ears pop when you swallow on a plane.
The Italian anatomist Bartolomeo Eustachi described small glands sitting on top of each kidney. Today we call them the adrenal glands. His beautiful copper-plate drawings sat unpublished for more than 150 years.
Why it mattered. The adrenals would later turn out to make adrenaline and cortisol, two of the body's most important hormones.
Barbaro described narrowing the opening in front of the lens to make the image sharper: the first recorded use of what we now call an aperture, or stopping down.
Why it mattered. Every camera since has let you trade light for sharpness this way.
16th century (the earliest reliable accounts; some claim older) · No. 049 ImmuneClear
Blowing smallpox scabs up the nose
Chinese physiciansChina
Chinese doctors ground up dried scabs from mild smallpox cases and blew the powder into a healthy child’s nose. The child usually got a mild illness and was then protected. Historians date reliable accounts to the 1500s; claims of a much older practice are uncertain.
Why it mattered. Deliberately giving a mild dose of a disease, called variolation, was the first attempt to train the immune system.
Portuguese missionaries and tradersNagasaki, Japan
Portuguese visitors brought the idea of coating food in flour and frying it to Nagasaki. The name probably comes from the Latin tempora, the Catholic fasting days when people ate fried vegetables and fish instead of meat. Japanese cooks then made the batter lighter and crisper.
Why it mattered. Frying spread around the world by trade, and each place made it its own.
The Chinese prince and scholar Zhu Zaiyu calculated how to split the octave into 12 equal steps, each the twelfth root of 2, about 1.0595 times the last, to many decimal places. Simon Stevin reached the same idea in Europe a few decades later.
Why it mattered. Every modern piano key is tuned this way: each is 1.0595 times the frequency of the one below.
The Chinese prince and scholar Zhu Zaiyu worked out an accurate mathematical way to split the octave into twelve equal steps and published it in 1584. His work got little official recognition in his lifetime.
Why it mattered. Equal steps are how pianos are tuned today, so music sounds right in every key.
Stevin's De Beghinselen der Weeghconst set out statics in Dutch: the lever, the centre of gravity, and his wreath of spheres draped over a double slope, which shows how forces combine.
Why it mattered. It gave engineers a clear method for balancing forces and turning effects.
In The Elements of Hydrostatics, the Flemish engineer Simon Stevin showed that the pressure of water on the bottom of a vessel depends only on its depth, not on the vessel's shape. He used it to explain Archimedes' push as the difference between pressure on the bottom and top of a body.
Why it mattered. It linked buoyancy to pressure, the way we still explain it (see PressureClear).
Young Galileo doubted the bathtub story: the extra overflow from a slightly silvery crown would be too small to see. In La Bilancetta he proposed a balance with the crown and pure gold hanging in water instead, where the difference shows clearly.
Why it mattered. It is the version of the crown test this box lets you try.
In his book on the weight of water, De Beghinselen des Waterwichts, Stevin showed that the push of water on the bottom of a vessel depends only on how deep the water is. The shape of the vessel and the amount of water do not matter. A thin tall tube can press on its base as hard as a wide tank of the same height.
Why it mattered. It was the first clear statement that liquid pressure depends on depth.
In his book De Beghinselen der Weeghconst (The Principles of Weighing), Stevin hung a loop of equal balls over a triangle with two slopes. The loop does not slide round by itself, so the few balls on the steep side must balance the many on the gentle side. From this he worked out how forces on ramps balance, and how to split one force into two.
Why it mattered. It was the first clear rule for adding and splitting forces, the idea behind force arrows today.
Simon Stevin and Jan Cornets de GrootDelft, Netherlands
Stevin and de Groot dropped two lead balls, one ten times heavier than the other, about 30 feet onto a board from the New Church tower in Delft. The two thuds sounded as one.
Why it mattered. A real, recorded experiment against Aristotle, years before the more famous Pisa story.
In De Beghinselen des Waterwichts (The Elements of Hydrostatics), Stevin showed that the force of water on the bottom of a vessel depends only on its depth and the area of the bottom, not on the vessel's shape or how much water it holds. He explained it by imagining parts of the water frozen solid without changing anything.
Why it mattered. It is the surprise behind Pascal's barrel and the first clear statement that pressure depends on depth alone.
Galileo's student Vincenzo Viviani later wrote that Galileo dropped balls of different weights from the Leaning Tower of Pisa to show they land together. Historians are not sure it really happened, but Galileo did argue it in his writing at Pisa.
Why it mattered. It became the most famous test of the idea that mass doesn't change how fast things fall.
Galileo warmed a glass bulb with a long neck in his hands and stood it upside down in water. As the air inside cooled, water crept up the neck. The rise and fall showed that something was getting hotter or colder, but it had no numbers on it.
Why it mattered. It was one of the first instruments to make heat visible, the ancestor of every thermometer.
Harington built a toilet with a cistern that flushed the bowl, and described it in a joke-filled book called The Metamorphosis of Ajax. Few copied it for almost two centuries.
Why it mattered. The idea of washing waste away with water came long before the pipes did.
Joan Carles Amat wrote a treatise on the five-course Spanish guitar, first printed in 1596. That edition is lost; the oldest surviving copy was printed in Lleida in 1626. It is considered the first known guitar treatise in Europe.
Why it mattered. It taught ordinary people to strum chords, which helped the guitar spread far beyond the court.
Much of the Siddha medical writing that survives is in Tamil verse on palm leaves: formulas for metals and minerals, diagnosis and diet. Historians such as Richard Weiss and Kamil Zvelebil date most of it to about the 16th century onwards, and leaves had to be copied again and again as they decayed.
Why it mattered. These manuscripts are the textual core of Siddha, and many are still unpublished.
In Kannauj, families have distilled flowers, herbs and even baked earth into attar for more than 400 years. They use the deg-bhapka method: copper stills over wood fires, with the scented steam caught in sandalwood oil. In 2014 Kannauj Perfume received a Geographical Indication tag.
Why it mattered. It is one of the world’s oldest living perfume traditions, still made by hand today.
In De Magnete, the English doctor William Gilbert showed that glass, sulphur and many gems attract things just as amber does. He called them 'electrica', from the Latin electricus, 'like amber', and built a pivoting needle to detect the pull.
Why it mattered. Electricity became a subject of its own, separate from magnetism.
Gilbert, doctor to Queen Elizabeth I, spent years testing magnets and published De Magnete. With a small magnetised sphere, a 'terrella', he showed that a compass behaves on it just as on the Earth, dipping near the poles. His conclusion: the Earth itself is a magnet.
Why it mattered. It explained why compasses work and made magnetism a subject for experiments rather than legends.
Teaching at Padua, Galileo wrote Le Mecaniche, a short book on levers, pulleys, screws and ramps. He showed they all follow one rule: a machine that lets a small force lift a big weight makes that force move much further. Marin Mersenne printed it in French in 1634.
Why it mattered. It is the first clear statement that machines transform effort but never create it.
Portuguese traders began bringing fans from East Asia to Europe from the 1400s. By the 1600s folding fans were fashionable across Europe, and whole trades grew up to paint and make them.
Why it mattered. The fan became one of the most important fashion accessories in Europe for three centuries.
Harriot, an English mathematician, measured refraction in many liquids and found the sine law. He wrote letters about refraction to Kepler, but he never shared the rule itself. It was found in his papers long after his death in 1621.
Why it mattered. A lesson every scientist learns: a discovery you do not publish may be credited to someone else.
In a book on optics, Kepler worked out that the lens of the eye focuses light into an upside-down picture on the retina, and that the retina, not the lens, is where seeing starts. He also explained how concave and convex lenses help short and long sight.
Why it mattered. It is the camera model of the eye we still use today.
Galileo rolled bronze balls down one ramp and up another. The ball climbed back to nearly its starting height, however gentle the second slope. Make the second ramp flat, he reasoned, and the ball would roll on for ever: it is friction that stops it.
Why it mattered. It was the first experiment to show that motion carries on unless something takes it away.
In a letter to his friend Paolo Sarpi, Galileo stated that a falling body covers distances that grow as the square of the time: 1, 4, 9, 16. He was timing balls rolling down gentle slopes, which slow the fall enough to measure.
Why it mattered. It is the first statement of s = ½ a t² tested against measurements.
Kepler used the Latin phrase camera obscura, “dark room”, and later built a portable tent version for drawing landscapes. He also explained how the eye's lens focuses an image on the retina.
Why it mattered. The English word “camera” comes from this: in Latin it simply means “room”.
Working from Tycho Brahe's careful observations, Kepler found that planets move on ellipses with the Sun at one focus, sweep out equal areas in equal times, and take longer to go round the further out they are. His first two laws came out in 1609 and the third in 1619.
Why it mattered. Newton later showed that an inverse-square pull explains all three laws at once.
In his book Dioptrice, written to explain Galileo's new telescope, Kepler described how light inside glass, meeting the surface at a steep slant, is not let out at all but is reflected back completely. He found this without knowing the exact law, which he never managed to find.
Why it mattered. Total internal reflection is what keeps light trapped inside every optical fibre today.
Aristotle's followers said ice floats because of its flat shape. Galileo argued, with experiments, that ice floats because it is lighter than the same volume of water, and that shape only matters through surface effects.
Why it mattered. It settled that density, not shape or weight, decides floating.
Santorio weighed himself, his food and his waste for about 30 years, often sitting on a weighing chair. Much of what he ate never left as visible waste; he called it insensible perspiration, lost through the skin and breath.
Why it mattered. It was the first measurement of the water we lose without noticing, about 0.7 litres a day.
Napier, the inventor of logarithms, published a set of numbered rods in his book Rabdologiae. Laid side by side, the rods turn multiplication into reading off and adding small numbers along diagonals.
Why it mattered. It broke multiplication into simple additions, the same idea as shift-and-add in a calculator chip.
In his Epitome of Copernican Astronomy, published in parts from 1618 to 1621, Kepler used the Latin word inertia, 'laziness' or 'idleness', for matter's resistance to being moved. His inertia made things tend to come to rest; the modern meaning came later.
Scheiner described the eye's anatomy and refraction in his book Oculus (1619). In a later book, Rosa Ursina, he reported cutting away the back coats of animal and human eyes so he could see the tiny inverted image on the retina itself, confirming Kepler.
Why it mattered. It showed with the eye itself that the image on the retina really is upside down.
The Dutch inventor Cornelis Drebbel is said to have rowed a leather-covered, oar-driven boat under the Thames, a few metres down, for King James I. Accounts are thin, so details are uncertain.
Why it mattered. It is often called the first navigable submarine.
Snellius, a professor at Leiden who also measured the size of the Earth, found a rule for refraction written with lengths rather than sines, but it is the same law. He died in 1626 without publishing it. Christiaan Huygens later read his manuscript and made his name known.
Why it mattered. Because Huygens spread the story, the law carries Snell's name in English, though he was not the first.
Aselli opened a dog that had just eaten and saw white threads on its intestines that oozed a milky liquid. He named them lacteals, milky veins. His book appeared in 1627, after his death.
Why it mattered. Lacteals are how the gut absorbs fat, and they were the first part of the lymph system to be found.
Aselli opened a dog that had just eaten and saw white threads on its intestines that oozed a milky liquid. He named them lacteals, milky veins. His book about them came out in 1627, two years after he died, with some of the first anatomy pictures ever printed in colour.
Why it mattered. Lacteals are how the gut absorbs fat, and they were the first part of the lymph system to be found.
Schickard described a machine with toothed wheels that added and subtracted, and carried from one wheel to the next, in letters to the astronomer Johannes Kepler. The machine itself was lost; modern copies have been built from his sketches.
Why it mattered. It is the earliest known design of a gear-driven calculator, though it had little influence at the time.
William HarveyLondon, England (printed in Frankfurt)
Harvey measured how much blood the heart pushes out with each beat and showed it was far more than the body could make from food. Blood must go round and round: the heart pumps it out through arteries and it comes back through veins.
Why it mattered. It made physiology, how the body works, a science of measurement and experiment.
William HarveyLondon, England (printed in Frankfurt)
Harvey published De Motu Cordis, On the Motion of the Heart and Blood. With experiments and simple sums he showed the heart pumps far more blood in an hour than the body could make from food. So the same blood must go out in the arteries and come back in the veins, in a circle.
Why it mattered. It is the moment circulation was born.
William HarveyLondon, England (printed in Frankfurt, Germany)
Harvey, an English doctor, published a short book called De Motu Cordis, On the Motion of the Heart and Blood. With experiments and simple sums, he showed the heart pumps far more blood than the body could ever make from food. So the same blood must flow out through arteries and back through veins in a circle.
Why it mattered. It is the moment the heart became a pump and circulation was born.
In his Dialogue on the Two Chief World Systems, Galileo argued that a stone dropped from a ship's mast lands at the foot of the mast even while the ship sails on, because the stone keeps the ship's forward motion as it falls.
Why it mattered. It explained why we don't feel the Earth moving: everything shares its motion.
The Jesuit mathematician Jean Leurechon gave the earliest known description of an ear trumpet, a funnel held to the ear to gather more sound. Such trumpets were used for about three centuries.
Why it mattered. A funnel does what the pinna does, only bigger: it collects sound from a wider area.
In Harmonie universelle, Mersenne set out how a string's pitch depends on its length (inversely), tension (as its square root) and weight per length (inversely as its square root). He also made the first absolute measurement of a note's frequency, about 84 vibrations a second.
Why it mattered. These laws are v = √(T ÷ μ) and f = v ÷ 2L, the rules behind every stringed instrument.
In a letter explaining machines to Constantijn Huygens, Descartes wrote that lifting 100 pounds one foot twice is the same as lifting 200 pounds one foot, or 100 pounds two feet. The effort of a job is weight multiplied by height.
Why it mattered. It measures a machine's job the way we measure work today.
The sine law is printed, and the rainbow explained
René DescartesLeiden, Dutch Republic
Descartes published the sine law in La Dioptrique, one of the essays printed with his Discourse on Method. In another essay, Les Météores, he used it to trace thousands of rays through a drop of water and showed that a rainbow appears about 42 degrees from the point opposite the Sun.
Why it mattered. It was the first time the law appeared in print, which is why the French call it the Snell–Descartes law.
In Two New Sciences, Galileo tells of a workman who said no suction pump could lift water more than eighteen cubits, about ten metres. Galileo believed the old idea from Aristotle that nature abhors a vacuum, and guessed that the water column simply broke under its own weight. His explanation was wrong, but the puzzle was real.
Why it mattered. The ten-metre limit set Galileo's pupils hunting for the true cause.
In his last book, Two New Sciences, Galileo showed with balls rolling down slopes that a falling body gains speed at a steady rate, so the distance grows with the square of the time. He also studied pendulums and argued that without air, all bodies would fall together.
Why it mattered. It turned falling into mathematics, the first step towards the idea of g.
In his last book, published in Leiden while he was under house arrest, Galileo stated that a body moving on a level surface keeps its speed as long as nothing gets in its way. For him 'level' followed the curve of the Earth, so his inertia was still slightly circular.
Why it mattered. Inertia became a principle of physics, backed by measurement.
Galileo GalileiPublished in Leiden, Dutch Republic
In Two New Sciences, Galileo showed that balls rolling down ramps speed up by the same amount every second. So the steady pull of weight does not give a steady speed, it gives a steady change of speed. The same book also studied how much force it takes to snap a beam.
Why it mattered. It broke Aristotle's link between force and speed and pointed towards force and acceleration.
Galileo GalileiLeiden (printed), from Arcetri, Italy
In Two New Sciences Galileo defined uniformly accelerated motion as one that gains equal amounts of speed in equal times. He timed bronze balls rolling down a grooved ramp with a water clock, and showed all bodies would fall together without air.
Why it mattered. It is the definition of acceleration still taught today: a = Δv ÷ Δt.
In Two New Sciences, Galileo argued that pitch is set by how many vibrations reach the ear each second, and compared vibrating strings with swinging pendulums, whose rhythm depends only on their length.
Why it mattered. It tied musical pitch to frequency, and the pendulum's natural rhythm is exactly what a swing resonates with.
Galileo GalileiPublished in Leiden, Dutch Republic
In Two New Sciences, Galileo described a pendulum whose string catches on a nail partway through its swing. Even though the swing changes shape, the bob rises back to almost exactly the height it started from. He argued that a ball rolling down a ramp gains a speed that depends only on how far it drops, not on the slope.
Why it mattered. It was an early hint that height and speed can be traded back and forth without anything being lost.
Galileo GalileiPublished in Leiden, Dutch Republic
Galileo timed balls rolling down gentle ramps using a water clock, and showed that falling things speed up steadily. He saw that a ball rolling on a level surface would keep going if nothing slowed it. The famous story of him dropping balls from the Leaning Tower of Pisa is probably a legend.
Why it mattered. His book Two New Sciences replaced arguments about motion with measurements.
A 19-year-old Blaise Pascal built a calculator to help his father, a tax official, with long sums. Turning dials moved gears, and a clever carry mechanism passed a 1 to the next wheel. About 50 were made over the next ten years.
Why it mattered. It showed that a machine, not a person, could do the carrying in arithmetic.
Aged about 19, Pascal built an adding machine to help his father, a tax official, with endless sums. Dials turned toothed wheels, and a clever weighted lever carried a 1 into the next wheel whenever a wheel passed 9. About 20 were made.
Why it mattered. Its automatic carry is the mechanical cousin of the carry that ripples through a binary adder.
While dissecting a body in Padua, the German anatomist Wirsung found the main duct running the length of the pancreas and had it engraved on a copper plate. He did not know what it carried, and was murdered the next year.
Why it mattered. It showed the pancreas sends something into the gut, the first clue to its digestive job.
Evangelista Torricelli and Vincenzo VivianiFlorence, Italy
Torricelli filled a glass tube with mercury and turned it upside down in a dish. The mercury dropped until the column was about 76 cm tall, leaving empty space above it. His young colleague Viviani most likely did the actual experiment, under Torricelli's guidance. Torricelli wrote that we live at the bottom of an ocean of air, whose weight holds up the mercury.
Why it mattered. It was the first barometer, and the first vacuum made on purpose.
Evangelista TorricelliFlorence, Grand Duchy of Tuscany
Torricelli filled a glass tube with mercury and turned it upside down in a bowl. The mercury fell to about 76 cm and stopped. He argued that the weight of the air outside, pressing on the bowl, was holding the column up.
Why it mattered. It turned air into a fluid with weight and pressure, and sent Pascal off on his own experiments.
Evangelista Torricelli; later Blaise Pascal and Florin PérierFlorence, Grand Duchy of Tuscany
Torricelli filled a glass tube with mercury and turned it upside down in a bowl. The mercury fell to about 76 cm and stopped, leaving empty space above it. The weight of the air outside was holding it up. In 1648 Pascal's brother-in-law carried the same tube up the Puy de Dôme in France, and the mercury stood lower at the top.
Why it mattered. It proved that air has weight and pushes on everything, which is what pressure means.
Torricelli proposed that water spurting from a hole in a tank leaves as fast as a drop falling from the water's surface down to the hole. Today we write it v = √(2gh).
Why it mattered. It was the first speed-from-pressure rule, and turned out to be a special case of Bernoulli's principle.
In his Principles of Philosophy, Descartes wrote that every moving thing tends to carry on in a straight line. A stone whirled in a sling keeps trying to fly off along the tangent, and only the sling stops it.
Why it mattered. It swapped the old idea that circles were natural for the modern one: straight is natural, turning needs a cause.
In his Principles of Philosophy, Descartes said God keeps the total 'quantity of motion', size times speed, the same in the universe for ever. He also gave seven rules for collisions. Most were wrong, because he ignored direction: speed has no sign, but motion does.
Why it mattered. The first conservation law of motion, and a famous mistake that pushed others to fix it.
In his Principles of Philosophy, Descartes set out laws of nature: each thing stays in the same state unless something changes it, and every moving thing tends to go on in a straight line.
Why it mattered. He was the first to make inertia straight, as Newton would.
In his Principles of Philosophy, Descartes wrote that a moving body keeps moving in a straight line unless something stops or turns it, and that going round a circle needs something pulling inwards.
Why it mattered. It made direction part of motion, the seed of the idea of velocity.
In his Principles of Philosophy, Descartes wrote down laws of nature. A thing stays at rest or keeps moving until something changes it, and on its own it moves in a straight line.
Why it mattered. It was the law of inertia stated in print, and Newton made it his first law.
Having heard of Torricelli's tube, the young Pascal repeated and extended it in Rouen with tubes, syringes, bellows and siphons of many shapes, filled with mercury, water, wine and oil. He published the results as Expériences nouvelles touchant le vide.
Why it mattered. Pascal learned to treat every liquid, and air, by the same rules, the groundwork for his principle.
The Flemish chemist van Helmont argued that food is not simply cooked. He proposed that an acid “ferment” in the stomach turns it into something new. His writings were published by his son four years after he died.
Why it mattered. It moved the question from heat to chemistry.
Florin Périer, for Blaise PascalClermont-Ferrand, France
Pascal was too ill to climb, so his brother-in-law Florin Périer carried a mercury tube up the Puy de Dôme volcano. At the foot the column stood at 26 inches 3½ lines; at the top it was 23 inches 2 lines, about 3 inches lower. Less air above means less weight pressing down.
Why it mattered. It proved that the air has weight and that air pressure falls as you go up.
Florin Périer, for Blaise PascalPuy de Dôme, near Clermont
At Pascal's request his brother-in-law measured the mercury column at the foot and the top of the Puy de Dôme, about 1 km higher. At the summit it stood about 3 French inches (roughly 8.5 cm) lower, and he repeated it several times before witnesses.
Why it mattered. It proved that the air's pressure comes from the weight of the air above, the same rule as depth in water.
Medical schools of Montpellier and LouvainMontpellier and Louvain
The Canon was read in European universities for centuries. It was used as a textbook at Montpellier and Louvain until about the mid-1600s, though its influence was fading by then.
Why it mattered. Few medical books have been taught for so long.
In Edo-period Japan, wandering komusō monks wore basket hats over their heads and played the shakuhachi, an end-blown bamboo flute with five holes. For them it was a tool for meditation, which they called suizen, blowing Zen. After the sect was abolished in the 1800s, the shakuhachi became a musical instrument anyone could learn.
Why it mattered. The shakuhachi shows the same edge-tone trick used for a completely different purpose: calming the mind.
William Harvey, famous for showing how blood circulates, studied chicks and deer embryos. In his book On the Generation of Animals he argued that all animals, including humans, begin from some kind of egg. The phrase ex ovo omnia, everything from an egg, became linked to his work.
Why it mattered. It pointed scientists towards the egg long before anyone had seen a mammal's egg.
Jean Pecquet, Olof Rudbeck and Thomas BartholinParis, Uppsala and Copenhagen
Pecquet found the thoracic duct emptying into the veins in 1651. The young Swede Rudbeck showed lymph vessels all over the body in 1652, and the Dane Bartholin published first, in 1653, and named them lymphatics. A famous quarrel over who came first followed.
Why it mattered. It showed that fluid leaking from the blood has its own way back.
Glisson boiled livers and filled their vessels with liquids to trace them. His Anatomia Hepatis was the first book printed in England about a single organ based on new research. It described the tough sheath around the liver's vessels, now called Glisson's capsule, although the Dutch anatomist Johannes Walaeus had seen it a few years earlier.
Why it mattered. It treated the liver as a structure to be mapped, not a mystery to be guessed about.
Otto von GuerickeRegensburg and Magdeburg, Germany
Around 1650 Guericke, mayor of Magdeburg, built the first air pump. At Regensburg in 1654 he pumped the air out of two copper half-spheres about 50 cm across, and two teams of horses could not pull them apart. He repeated the show with sixteen horses in Magdeburg around 1656, and in Berlin in 1663. The air outside was pressing the halves together with a force of roughly 20,000 newtons.
Why it mattered. It showed, loudly and in public, how strong ordinary air pressure is.
In his Traité de l'équilibre des liqueurs, Pascal stated that pressure applied to a liquid in a closed vessel is passed on equally in all directions. He described a vessel with two openings, one a hundred times bigger than the other: one man pushing the small piston could hold back a hundred pushing the big one. The treatise was printed in 1663, a year after his death.
Why it mattered. This is Pascal's principle, and his idea is exactly the hydraulic press, brake and jack.
In a book about the body's glands, the English doctor Thomas Wharton named the gland in the neck the thyroid. The name comes from the Greek word for a shield, because of the shape of the cartilage nearby. He guessed it was there to help round out the shape of the neck.
Why it mattered. Scientists could now point at the thyroid by name, even though its real job was still a mystery.
Huygens worked out correct rules for colliding hard balls by picturing the same collision seen from a boat drifting along a canal. He found that mass times velocity, counted with direction, is conserved, and for hard balls mass times speed squared too. His book De motu corporum ex percussione was only printed after his death.
Why it mattered. It fixed Descartes's rules and hinted that there are two conserved quantities, not one.
Huygens worked out the correct rules for bouncy collisions in 1656 and told the Royal Society about them in 1669. His full book on collisions was printed only in 1703, after his death. In 1659 he also found the formula for the outward pull you feel going round a curve.
Why it mattered. His collision rules are the ideas behind Newton's third law and momentum.
The Dutch scientist Christiaan Huygens is widely credited with the first working magic lantern. The oldest known document about it is his page of sketches of a skeleton taking off its skull, thought to date from 1659. A lamp shone through a small painted glass slide, and a lens threw a big, bright copy of it onto a wall.
Why it mattered. Lamp, slide, lens and screen: every projector since, even a digital one, still has these four parts.
Working on pendulum clocks, Huygens worked out that the outward tug on a whirled weight grows with the square of its speed and falls with the radius: in today's terms m v² ÷ r. He wrote it up as De vi centrifuga, which was only printed after his death, in 1703.
Why it mattered. It was the first correct formula for circular motion.
Boyle's assistant Robert Hooke built a better air pump with a glass globe, so people could watch what happened inside. With it Boyle found that sound fades in a vacuum, flames go out and a mercury barometer sinks as the air is removed. He wrote it up in New Experiments Physico-Mechanicall, Touching the Spring of the Air in 1660.
Why it mattered. It turned the vacuum into a place for careful, repeatable experiments.
Boyle and his assistant Hooke built an air pump and sucked the air out of glass jars holding mice, birds and insects. The animals collapsed, and a candle went out. In 1662 Boyle published the rule now called Boyle’s law: squeeze a gas into half the space and its pressure doubles.
Why it mattered. Boyle’s law is exactly how you breathe: your chest grows, the pressure inside drops, and air rushes in.
Using an air pump built with his assistant Robert Hooke, Boyle pumped the air from a glass jar holding a ticking watch. The ticking grew fainter as the air went and returned when it was let back in.
Why it mattered. It showed that sound needs air to travel, while light passed through the empty jar untouched.
While working on spring-driven watches, Hooke found that a spring's stretch grows in step with the load on it. He later wrote that he had known this since 1660, but kept it to himself.
Why it mattered. The rule was found by someone trying to make a better clock, not a theory of materials.
Looking through an early microscope, Malpighi saw that a lung is not a solid lump of flesh. It is full of tiny air-filled bubbles, like a honeycomb, wrapped in the thinnest blood vessels, the capillaries. He studied frog lungs and described them in letters called De pulmonibus.
Why it mattered. He found the alveoli, the air sacs where oxygen finally crosses into your blood.
Harvey could not see how blood got from arteries to veins. Malpighi looked at a frog's thin lung through an early microscope and saw tiny vessels joining the two. He described them in De pulmonibus in 1661.
Why it mattered. It closed the last gap in Harvey's circle.
Harvey could not see how blood got from arteries to veins. Malpighi looked at a frog's thin lung under an early microscope and saw tiny vessels joining the two. He described them in De pulmonibus in 1661.
Why it mattered. It closed the last gap in Harvey's circle.
At about 19, Bellini published a study of the kidney's structure. He showed that it is not a solid lump of flesh but is full of tiny tubes that carry urine towards the pelvis. The collecting ducts are still called the ducts of Bellini.
Why it mattered. It was the first sign that the kidney works through countless tiny tubes.
Boyle trapped air in the short end of a J-shaped tube and poured mercury into the long end. Doubling the pressure halved the volume of the air, so pressure times volume stayed the same. Richard Towneley and Henry Power had noticed it too, and Edme Mariotte found it again in France in 1679.
Why it mattered. It was the first law linking the pressure of a gas to its volume.
Fermat guessed that light always takes the path that needs the least time, and that it goes more slowly in water and glass than in air. In a letter to Marin Cureau de la Chambre, he showed that this idea gives exactly the sine law. Like a lifeguard who runs further on sand to swim less, light bends to save time.
Why it mattered. It explained the law with one simple idea, and predicted that light is slower in denser materials.
Robert Boyle, with Robert Hooke; helped by Richard Towneley and Henry PowerOxford, England
Boyle trapped air in the short, closed end of a J-shaped glass tube and poured mercury into the long end. Every time he doubled the push, the trapped air shrank to half its size. Towneley and Power had spotted the same pattern, and Boyle printed the result in the second edition of his book on the "spring of the air".
Why it mattered. It was one of the first laws of nature written as a rule linking two measured numbers: pressure times volume stays the same.
Swammerdam sealed a frog's muscle and nerve in a glass tube with water and made it contract by touching the nerve. The water level did not rise: if anything it dropped a little. So nothing flows into a working muscle. His notes were published only in 1737, in Biblia Naturae.
Why it mattered. It disproved the old idea that muscles contract by filling with spirit or fluid.
Thomas Walgensten and Athanasius KircherParis, Rome and Copenhagen
The Danish mathematician Thomas Walgensten toured Europe showing the lantern from 1664, and he is credited with calling it the laterna magica. The Jesuit scholar Athanasius Kircher, who had written about projecting images in 1645, described the magic lantern in the 1671 edition of his book on light. Historians still argue about how much each man added.
Why it mattered. Travelling shows made people everywhere used to sitting in the dark and watching pictures on a screen.
Willis’s “The Anatomy of the Brain” mapped the brain and its nerves in careful detail, and he is credited with coining the word neurology. He also traced the nerves that serve the heart and gut.
Why it mattered. It moved the study of the mind into the brain itself.
Thomas Willis, with drawings by Christopher WrenOxford, England
Willis’s Cerebri Anatome was the most detailed study of the brain yet. It introduced the term neurology and described the ring of arteries at the base of the brain, still called the circle of Willis.
Why it mattered. It placed functions like memory and movement in the brain’s tissue rather than its hollow ventricles.
Marcello Malpighi looked at the tongue and skin through an early microscope. In a 1665 letter on the outer organ of touch (De externo tactus organo) he described tiny bumps called papillae and a soft layer under the tough outer skin. The living bottom part of the epidermis is still sometimes called the Malpighian layer.
Why it mattered. It showed that skin is built in layers, each with its own job.
Using an early microscope, Malpighi described small round bodies scattered through the kidney's outer layer, linked to its blood vessels. We now call them glomeruli; for a long time they were known as Malpighian bodies.
Why it mattered. He found the filters of the kidney, though nobody yet knew what they did.
Isaac NewtonWoolsthorpe Manor, Lincolnshire, England
Sent home from Cambridge by the plague, the young Newton wondered whether the pull that brings an apple down might reach as far as the Moon. He told the story himself, much later, to his friend William Stukeley, who published it. There is no evidence the apple hit his head.
Why it mattered. It captures Newton's great leap: the same gravity works on Earth and in the sky.
The English scientist Robert Hooke described how sound could be carried far along a tight wire or string, much further than through the air. It is the idea behind the tin-can telephone that children still make.
Why it mattered. Long before electricity, people knew a solid line could carry a voice.
In Elementorum myologiae specimen, Steno described a muscle as a bundle of fibres joined to tendons, and explained contraction as a change of shape of those fibres, drawn with geometry.
Why it mattered. He put the fibre, not a mysterious spirit, at the centre of muscle action.
People argued about whether the moving of the lungs or the air itself kept an animal alive. In front of the Royal Society, Hooke pumped air into a dog's opened lungs with bellows. When he kept the lungs still and just let fresh air flow through them, the dog lived, and it failed when the fresh air stopped.
Why it mattered. It showed that fresh air, not the movement, is what the body needs, an early step toward breathing machines.
People argued about whether the moving of the lungs or the air itself kept us alive. In front of the Royal Society, Hooke pumped air into an opened dog’s lungs with bellows. Even when he kept the lungs still and just let fresh air flow through, the dog lived, and it failed when the fresh air stopped.
Why it mattered. It showed that fresh air, not movement, is what the body needs, and it was an early step toward artificial ventilation.
John Wallis, Christopher Wren and Christiaan HuygensLondon, England
The Royal Society asked for the true laws of collision. Wallis sent rules for soft bodies that stick (26 November 1668); Wren's rules for hard, bouncing bodies were read on 17 December and printed on 11 January 1669; Huygens sent his too. All three rested on the same idea: the total momentum, counted with direction, never changes.
Why it mattered. The conservation of momentum became an agreed, tested law of nature.
Christiaan HuygensParis, published in the Journal des Sçavans
Huygens had solved the puzzle of hard balls colliding back in the 1650s. In 1669 he published his rules and pointed out that if you multiply each ball's mass by its speed squared and add them up, the total is the same before and after a bouncy collision. The Royal Society in London printed a Latin version soon after.
Why it mattered. It was the first time the quantity mass times speed squared was shown to be kept in a collision.
Kerckring, a Dutch doctor, described the ring-shaped folds that line the inside of the small intestine in his atlas, Spicilegium anatomicum. They are still sometimes called the valves of Kerckring. Today they are known as circular folds.
Why it mattered. The folds are the first of three layers of folding that give the gut a huge surface for soaking up food.
The Dutch doctor Regnier de Graaf studied the ovaries of rabbits and other mammals and described small fluid-filled bubbles on their surface. He thought each bubble was an egg. In fact each one holds a far smaller egg inside. We still call a ripe one a Graafian follicle.
Why it mattered. He found the follicle, the bubble that ripens and releases an egg every month.
With prisms, Newton split sunlight into a spectrum and recombined it into white. He reported the work to the Royal Society in 1672 and later wrote it up in his book Opticks (1704).
Why it mattered. It showed that colour is in the light and in how we sense it, the starting point for colour vision science.
Newton let a beam of sunlight into a dark room through a hole and passed it through a glass prism. White light spread into a band of colours, because each colour is refracted by a slightly different amount. He published it in 1672 in the Royal Society's journal.
Why it mattered. It showed that a material's refractive index depends on colour, the reason prisms and rainbows split light.
Leibniz showed a model of his stepped reckoner to the Royal Society in London in 1673. Its stepped drum, a cylinder with teeth of different lengths, let a machine multiply by adding over and over. Stepped drums drove calculating machines for the next 300 years.
Why it mattered. Multiplying by repeated, shifted addition is exactly how simple calculator chips multiply.
At the end of Horologium Oscillatorium, his great book on pendulum clocks, Huygens printed thirteen theorems on 'centrifugal force' without their proofs. It is where the name first appeared in print.
Why it mattered. Scientists across Europe, including Newton, could now calculate the force needed for any circle.
In his Traité de la percussion, Mariotte tested collisions with balls hung on threads, the arrangement we now call Newton's cradle, and sorted collisions into elastic and inelastic ones. Newton later credited his pendulum experiments.
Why it mattered. The first recorded Newton's cradle, a century before Newton's name was attached to it.
In Horologium Oscillatorium Huygens published his theorems on circular motion: the pull needed grows with the square of the speed and shrinks with the radius, what we now write as v² ÷ r.
Why it mattered. It explains the huge accelerations of fan blades and spinning drums.
Boyle heated lead and tin in sealed glass vessels. When he opened them and weighed the metal's ash, called a calx, it was heavier than the metal. He guessed that particles of fire had passed through the glass and stuck to it.
Why it mattered. A real clue, misread: he opened the vessel before weighing, so air rushed in and the extra weight was really oxygen.
In his book Tractatus quinque, the young Oxford doctor Mayow argued that air holds a special part, which he called nitro-aerial spirit, that is used up by both a burning flame and a breathing animal. He also described how chest muscles and the diaphragm make the chest bigger, so the lungs fill like bellows. He guessed right a century before oxygen was named.
Why it mattered. He saw that breathing and burning use the same part of the air, and that the chest works like a pump.
Using his own tiny, powerful lenses, the Delft cloth merchant van Leeuwenhoek described his blood as small round globules floating in a clear liquid, and later measured them. Jan Swammerdam had probably seen red cells in frog blood earlier, but his notes were only printed decades after his death.
Why it mattered. Blood turned out to be a liquid full of cells, not a simple fluid.
The English physician Thomas Willis wrote that the urine of people with diabetes was wonderfully sweet, like sugar or honey. He tasted it himself, as doctors then did, but did not guess that it held sugar.
Why it mattered. It rediscovered in Europe what Indian doctors had long known, and later gave diabetes 'mellitus', honeyed.
Gaspar Sanz published a big method for the five-course baroque guitar in 1674. It mixed strummed pieces (rasgueado) with plucked ones (punteado), from courtly dances to popular tunes. It became the most complete baroque guitar method.
Why it mattered. Guitarists still play Sanz today, and still switch between strumming and picking.
Robert Boyle described a glass bulb with a long, slender stem that floats in a liquid: the deeper it sinks, the less dense the liquid. He designed it to catch counterfeit gold coins, and coined the name 'hydrometer'.
Why it mattered. Hydrometers made density a quick everyday measurement.
Christiaan Huygens, with the clockmaker Isaac ThuretParis, France
Huygens designed a watch regulated by a spiral balance spring and patented a pocket watch. Hooke, who had experimented with spring-regulated watches in the 1660s, accused him of taking the idea, and a bitter priority fight followed.
Why it mattered. A balance swinging on a spring beats at a steady rate whatever its swing, because the spring obeys Hooke's law. Pocket watches became accurate enough to be useful.
Timing the eclipses of Jupiter's moon Io, Rømer noticed they came late when Earth was far from Jupiter. Light, he concluded, takes time to cross space. His figures implied a speed of roughly 220,000 km/s.
Why it mattered. The fastest speed there is turned out to be finite, and measurable.
At the end of his book on helioscopes, Hooke printed a string of letters, ceiiinosssttuu, to 'fill the vacancy' of the page. It was an anagram: a way to claim a discovery without yet saying what it was.
Why it mattered. Scientists of the time used anagrams to prove they had an idea first while keeping it secret.
Mariotte, a French priest and scientist, found the same rule on his own and wrote it up in his Discourse on the Nature of Air. He added an important warning: it only works if the temperature does not change. In the same book he coined the word "barometer".
Why it mattered. His warning about temperature pointed the way to the next gas laws.
Antonie van Leeuwenhoek (with Johan Ham)Delft, Netherlands
Using his own tiny, powerful single-lens microscopes, the cloth merchant Antonie van Leeuwenhoek saw thousands of swimming cells with long tails in a sample of semen. A medical student, Johan Ham, had first pointed them out to him. He described them in a letter to the Royal Society in London.
Why it mattered. For the first time, people could see the cell that carries the father's half of a new life.
Peyer, a Swiss doctor, described clusters of little lumps in the wall of the small intestine. He thought they were glands. We now call them Peyer's patches and know they are part of the immune system.
Why it mattered. They are guard posts where the body checks what is passing through the gut.
Itty Achuden, with Hendrik van RheedeKochi, printed in Amsterdam
The Ezhava physician Itty Achuden dictated in Malayalam what his family’s palm-leaf manuscripts said about the plants of Malabar, checked by the Konkani physicians Ranga Bhat, Vinayaka Pandit and Appu Bhat. The Dutch governor van Rheede had it published with 794 copper engravings.
Why it mattered. Indian healers’ plant knowledge became a founding book of tropical botany.
In 1676 Hooke hid a discovery in a scrambled Latin puzzle, ceiiinosssttuv. Two years later he gave the answer, ut tensio, sic vis: as the stretch, so the force. Pull a spring twice as hard and it stretches twice as far.
Why it mattered. Hooke's law is how every spring scale and force meter turns a force into a length you can read.
Huygens, a Dutch scientist working in Paris, imagined every point on a wave of light sending out tiny wavelets. If the wavelets move more slowly in glass, the front of the wave swings round as it enters, like a line of marchers stepping from road onto mud. He read his idea to the Academy in 1678 and printed it in his Treatise on Light in 1690.
Why it mattered. It explained Snell's law with waves, and it is still the clearest picture of why light bends.
In Lectures de Potentia Restitutiva, or Of Spring, Hooke gave the answer: ut tensio, sic vis. The force of any spring is in proportion to how far it is stretched. He showed it held for coiled springs, watch springs, wires and even wood.
Why it mattered. It is the first law of elasticity, and it is still exactly how we design springs, scales and structures.
In letters to Isaac Newton, Hooke suggested that a planet's orbit is a straight-line motion constantly bent by an attraction towards the Sun. The inward pull, not an outward one, was the thing to explain.
Why it mattered. It pointed Newton towards thinking of an inward, centre-seeking force.
Papin showed the Royal Society a sealed iron pot that trapped steam, raising the pressure and the boiling point of the water inside. It could soften bones in a few hours. To stop it bursting he added a safety valve: a weighted lever that lets steam out when the pressure gets too high.
Why it mattered. It was the ancestor of every pressure cooker and every safety valve.
In 1674 Hooke suggested that all heavenly bodies attract each other, and that an orbit is a straight motion bent by that pull. In letters to Newton in 1679–80 he proposed that the pull falls off with the square of the distance. Hooke could not do the mathematics to prove it; the two men argued about credit for the rest of their lives.
Why it mattered. Hooke's letters pushed Newton to work out orbits under an inverse-square force.
Borelli's De Motu Animalium, published just after his death, treated bones as levers and muscles as the forces that pull on them. He worked out that muscles must pull many times harder than the weights they hold, because they attach so close to the joint.
Why it mattered. It founded biomechanics and is the reason chapter 4 of this box can work out your biceps force.
Borelli, a mathematician, studied how animals walk, run, swim, jump and fly using the rules of machines. He treated bones as levers pulled by muscles, and worked out how the body shifts its centre of gravity to move. His book De Motu Animalium came out just after he died.
Why it mattered. He is often called the father of biomechanics.
The Hotteterre family of instrument makersParis, France
Toward the end of the 1600s, makers in Paris, apparently the Hotteterre family, rebuilt the flute. They made it in separate joints with a tapering (conical) inside and added one key for the little finger. The new flute was sweeter, better in tune and could play music written for violins.
Why it mattered. Its one key was the first step on the road to the many-keyed modern flute.
Hooke held a card against a spinning toothed brass wheel. The faster it spun, the more clicks each second and the higher the note, so he could make a sound of known frequency on demand.
Why it mattered. It showed directly that pitch is frequency, the idea behind every sound chapter since.
Duverney's Traité de l'organe de l'ouïe was the first whole book on the structure, workings and diseases of the ear. With the physicist Edme Mariotte he even guessed that different parts of the cochlea answer different pitches.
Why it mattered. It turned the study of the ear into a subject of its own, now called otology.
In a short manuscript sent to Edmond Halley, De motu corporum in gyrum, Newton introduced vis centripeta, 'centre-seeking force', a name that mirrors Huygens's centrifugal force. He showed that an inverse-square centripetal pull gives Kepler's orbits.
Why it mattered. It turned the question round: circles need an inward pull, and gravity can be it.
Leibniz published his calculus, a method for finding the rate of change at a single instant. Newton had worked out his own version, 'fluxions', in the 1660s. Instantaneous speed is the limit of distance ÷ time over a vanishing interval.
Why it mattered. It gave a precise meaning to what a speedometer shows.
Halley visited Newton to ask what path a planet would follow if the Sun's pull weakened with distance. Newton said he had already worked it out. In November he sent Halley a short paper, De motu corporum in gyrum, which grew into a whole book.
Why it mattered. Without Halley's question, the Principia might never have been written.
In the journal Acta Eruditorum, Leibniz published a 'brief demonstration of a notable error of Descartes'. The true 'living force' (vis viva) of a moving body, he said, is mass times speed squared, not mass times speed. Cartesians fought back, and the vis viva controversy lasted about fifty years.
Why it mattered. It separated the ideas we now call momentum and kinetic energy.
Gottfried Wilhelm LeibnizPublished in Acta Eruditorum, Leipzig
Descartes had said the world keeps a fixed amount of 'motion', measured as mass times speed. In a short paper called the Brevis demonstratio, Leibniz argued that this was a mistake and that the true measure of a moving body's force goes with its speed squared. He later called it vis viva, Latin for 'living force'.
Why it mattered. It started a famous argument that lasted decades, and vis viva became what we now call kinetic energy.
Brunner, a Swiss anatomist, described glands in the wall of the duodenum, the first part of the small intestine, now called Brunner's glands. They make a slippery, alkaline mucus. A few years earlier, in 1683, he had removed a dog's pancreas and seen it become very thirsty, an early clue to diabetes.
Why it mattered. The mucus helps protect the gut from the acid that arrives from the stomach.
Principia defined centripetal force (Definition 5) and used it for the Moon, planets and tides. In one passage Newton described a bucket of water set spinning: as the water starts to turn with it, its surface climbs the sides into a curve, a sign of real rotation.
Why it mattered. It made m v² ÷ r part of one system of mechanics, and started a long argument about what 'really rotating' means.
In Projet d'une nouvelle mécanique, Varignon showed that the moment of a combined force about any point equals the sum of the moments of its parts. You can split a slanted push into pieces and add their torques.
Why it mattered. It made working out torques in real machines a matter of simple addition.
In the Principia, Newton explained the slow drift of the equinoxes, first noticed by Hipparchus: the Sun and Moon pull on Earth's equatorial bulge, and that torque makes the spinning Earth's axis trace a circle every 26,000 years or so.
Why it mattered. The first explanation of precession: a torque turning a spin's direction, not its speed.
Newton's Principia showed that every mass pulls every other mass with a force proportional to both masses and inversely proportional to the square of the distance. With it he explained falling, Kepler's laws, the tides and the paths of comets. Edmond Halley paid for the printing.
Why it mattered. It was the first law of nature that worked the same everywhere in the universe.
Newton's Principia defines 'quantity of motion' as velocity and quantity of matter together, and his second law says a force changes it. Conservation of momentum drops out as a corollary of his laws. He credits Wren, Wallis, Huygens and Mariotte for the collision experiments.
Why it mattered. Momentum became the quantity that forces change, the basis of all later mechanics (see NewtonClear).
Newton's Principia defined 'quantity of matter', our mass, and the 'vis inertiae', the power of every body to resist changes to its motion. His first law says every body stays at rest or in steady straight-line motion unless a force acts, and his second makes mass the measure of that resistance: F = m a.
Why it mattered. Inertia and mass became the foundation of all of mechanics.
In the Principia, Newton defined an impressed force (vis impressa) as an action on a body that changes its state of rest or steady motion. His second law said the change in motion is proportional to the force, and in the same direction. He also showed that two forces combine like the sides of a parallelogram.
Why it mattered. Force stopped being a vague push and became a precise quantity with a size and a direction.
In the same year as the Principia, Varignon published Projet d'une nouvelle mécanique, a book built on combining forces. He used the parallelogram rule to explain levers, pulleys and ramps with geometry.
Why it mattered. It helped make force diagrams with arrows the everyday tool of engineers.
Newton's Principia set out his three laws of motion. The second says a force produces an acceleration, a = F ÷ m, and the first that without a force velocity stays the same in speed and direction.
Why it mattered. Speed, velocity and acceleration became the language of all mechanics.
In the Principia, Newton worked out the speed of sound from the springiness and density of air. He got about 298 m/s, some 15 % too low, and could not explain the gap.
Why it mattered. It was the first attempt to predict a wave's speed from the medium it travels through, the idea that v is set by the medium, not the source.
Newton's Principia opened with three laws of motion, written in Latin: inertia, force changing motion, and every action having an equal and opposite reaction. Halley edited the book and paid for the printing himself. The same laws explained falling apples, tides and planets.
Why it mattered. For the first time one set of rules covered motion on Earth and in the sky.
Havers, a young English doctor, published Osteologia Nova, New Observations of the Bones. He described the tiny channels that run along the hard outer bone, now called Haversian canals. They carry blood vessels and nerves right through the bone.
Why it mattered. It showed that bone has plumbing, a first hint that it is living tissue.
The first English patent in the category of washing machines was issued in 1691. For centuries before that, people washed clothes in rivers and tubs, beating out the dirt with wooden paddles and scrubbing with ash lye or soap.
Why it mattered. It shows that people were already dreaming of a machine to take the pain out of washing day more than 300 years ago.
The Dutch microscope maker Nicolaas Hartsoeker drew a tiny curled-up person, a homunculus, inside the head of a sperm. He did not claim to have seen it; he drew it to show an idea many people then held, that a miniature person was already formed and only had to grow.
Why it mattered. It is a famous example of a wrong idea that microscopes and careful experiments later overturned.
Amontons told the Paris Academy of Sciences that friction is proportional to the load and does not depend on the area of contact. Many academicians found the second rule hard to believe, and it had to be checked again.
Why it mattered. These are still the rules engineers use every day: F = μ × N, whatever the size of the block.
The famous violin maker also built guitars with five pairs of strings. The Rawlins, made in 1700, is one of only a handful of Stradivari guitars that survive; another, the Sabionari of 1679, can still be played. The Rawlins is kept at the National Music Museum in Vermillion, South Dakota.
Why it mattered. The best instrument makers of the age treated the guitar as worth their finest work.
Cristofori came to Florence in 1688 to look after the instruments of Prince Ferdinando de' Medici. A Medici inventory of 1700 lists his 'arpicembalo' of new invention that 'makes the soft and the loud'. Instead of plucking, it hit the strings with small hammers.
Why it mattered. For the first time, how hard you pressed a key decided how loud the note was.
Newton published, without his name, a short paper in Latin about heat. He noted that a hot object cools faster when it is much hotter than its surroundings. Today the idea is often written with a breeze in mind: moving air takes heat away faster.
Why it mattered. It is the root of the physics of how hot air passes heat into food.
Isaac Newton (published anonymously)London, England
A short paper in Latin called Scala graduum caloris appeared without a name in the Royal Society's journal. It is known to be Newton's work. It suggested that a hot object cools faster when it is much hotter than its surroundings, and slower as the gap shrinks.
Why it mattered. It was the first rule for heat transfer and is still the starting point for how engineers describe cooling by moving air.
In The Miner's Friend, Savery sold his steam pump for draining mines by saying how many horses it could replace. Mine owners paid for horses, so a horse was a unit they understood.
Why it mattered. Comparing engines with horses led to the horsepower.
Amontons, who had been mostly deaf since boyhood, built a thermometer that read temperature from the pressure of trapped air. He saw that equal drops in temperature gave equal drops in pressure. If you kept cooling, the pressure would one day reach nothing, which he put at about minus 240 °C.
Why it mattered. It was the first hint that there is a coldest possible temperature, absolute zero.
Building on Johann Becher's ideas, Stahl taught that everything that burns holds a fire substance, phlogiston, which escapes in the flame. Charcoal was almost pure phlogiston; a metal was its calx plus phlogiston. The idea explained a lot and ruled chemistry for most of the century.
Why it mattered. It was the first big theory of burning, and it was wrong in a way that pushed chemists to start weighing things.
Jacques-Martin Hotteterre, called le RomainParis, France
Jacques-Martin Hotteterre published Principes de la flûte traversière, a guide to the transverse flute, the recorder and the oboe. It showed how to hold the flute, shape the lips and finger each note. It is the earliest known method book for the transverse flute in any language.
Why it mattered. It turned flute playing into a skill that anyone could learn from a book.
The writer Scipione Maffei published an enthusiastic article about Cristofori's invention in the Giornale de' letterati d'Italia, with a drawing of the hammer mechanism. It was translated into German in 1725. Some musicians of the time still found the new sound too soft and dull.
Why it mattered. The article carried the idea across the Alps, where the next makers learned it.
Daniel Gabriel FahrenheitAmsterdam, Dutch Republic
Fahrenheit, a glassblower born in Danzig, made reliable thermometers, first with alcohol and by 1714 with mercury. In 1724 he described his scale to the Royal Society in London. Two of his thermometers made in the same way gave the same reading.
Why it mattered. For the first time, people in different places could compare temperatures as numbers.
Schulze found that a mixture containing silver salts turned dark where light hit it, not because of heat. He made temporary words appear by covering a bottle with stencils.
Why it mattered. Light-sensitive silver was the heart of photography for the next 250 years.
Muhammad Shah ruled from Delhi from 1719 to 1748 and was nicknamed Rangila, the colourful one, for his love of the arts. At his court the khayal style of singing flourished under musicians like Niamat Khan Sadarang. Khayal is lighter and more flowing than dhrupad, and it suited a lighter drum.
Why it mattered. The music of his court helped create the demand that the tabla would fill.
The German anatomist Abraham Vater described the small swelling where the bile duct and the pancreatic duct meet and open into the duodenum. It is still called the ampulla of Vater.
Why it mattered. This tiny opening explains why a gallstone can block the pancreas and cause pancreatitis.
Sidhar Khan Dhadi is the earliest name linked to the tabla in historical records. He is said to have been a pakhawaj player who developed a gentler way of playing with just two fingers near the edge of the drum. His followers became the Delhi gharana, the oldest of the tabla schools.
Why it mattered. His crisp, fingertip style is what makes the tabla sound different from the booming pakhawaj.
Three Cristofori pianos survive, from 1720, 1722 and 1726. The oldest is at The Metropolitan Museum of Art in New York and has 54 keys, against 88 on a modern piano. Its full name was gravicembalo col piano e forte, a harpsichord with soft and loud, later shortened to piano. It already has an escapement, which lets the hammer fly free after it strikes, and dampers that silence a string when you let go.
Why it mattered. The basic ideas inside every piano today are already in this instrument.
Lady Mary Wortley Montagu; Onesimus and Cotton MatherLondon, England; Boston, America
Lady Mary Wortley Montagu had seen variolation in Constantinople and had her daughter inoculated in London in 1721. In Boston the same year, an enslaved West African man, Onesimus, told Cotton Mather how it was done in his homeland, and inoculation was tried during an epidemic.
Why it mattered. Knowledge from Turkey and West Africa brought the idea to Europe and America.
's Gravesande dropped brass balls of different masses into soft clay. Balls made equal dents when their heights were inversely proportional to their masses, which means the dent follows mass times speed squared. He switched sides to Leibniz.
Why it mattered. An experiment showing that damage follows energy, not momentum: the myth-buster in this box.
Euler worked out the idea that a material has its own stiffness, separate from the shape of the object made from it. It is what we now call the elastic or Young's modulus.
Why it mattered. It turned Hooke's rule about springs into a rule about materials.
Stephen Gray sent the 'electric virtue' from a rubbed glass tube along hundreds of feet of thread hung on silk. Metal wire and damp thread carried it; silk did not. He had found conductors and insulators.
Why it mattered. Electricity could move from place to place: the first hint of a current.
Working on rivers and aqueducts, Pitot pointed a bent glass tube into the flow of the Seine. The faster the water, the higher it rose in the tube. He published the idea in 1732, and Henry Darcy gave it its modern form in 1858.
Why it mattered. Pitot tubes still tell every airliner how fast it is flying through the air.
Hales, a vicar and scientist, tied a glass tube about 9 feet long into an artery of a mare. The blood rose about 8 feet 3 inches up the tube and bobbed with every heartbeat. He described it in his book Haemastaticks in 1733.
Why it mattered. It was the first measurement of blood pressure.
Hales, a vicar and scientist, tied a glass tube about 9 feet long into an artery of a mare lying on her back. The blood rose about 8 feet 3 inches up the tube and bobbed with every heartbeat. He described it in his book Haemastaticks in 1733.
Why it mattered. It was the first measurement of blood pressure, the push the heart gives the blood.
Hales, a clergyman and scientist, connected a long glass tube to an artery in a horse's neck. The blood rose about 8 to 9 feet and rose and fell with each heartbeat. He had measured blood pressure as a height of liquid, ρ g h.
Why it mattered. It was the first measurement of blood pressure, and it showed the pulse as a pressure wave.
Daniel BernoulliBasel, Switzerland (book printed in Strasbourg)
In his book Hydrodynamica, Bernoulli pictured air as countless tiny particles flying in all directions. Their hits on the walls of a container make the pressure, and faster particles mean a hotter gas. He even showed why this gives Boyle's law.
Why it mattered. It was the first kinetic theory of gases, more than a hundred years before most scientists accepted it.
Daniel BernoulliWritten in St Petersburg; printed in Strasbourg
Bernoulli's book on the forces and motions of fluids showed that where water flows faster, its pressure is lower. He measured pressure by poking an open tube through a pipe's wall and watching how high the water rose. The same book sketched the first kinetic theory of gases.
Why it mattered. It gave the principle its name and began the science it called hydrodynamics.
Henri-Louis Duhamel du Monceau, later John HunterFrance and London, England
Madder, a plant dye, turns new bone red. Duhamel fed it to pigs and birds on and off, and found red and white rings, like tree rings, laid down under the bone's outer skin. Years later John Hunter used madder and lead pellets in pigs to show bone is also eaten away on the inside as it grows.
Why it mattered. It proved bone is built up and removed all the time: it remodels.
Émilie du Châtelet combined Leibniz's argument with 's Gravesande's clay results in her physics textbook, and argued that vis viva, m v², is what a moving body can do. She later translated Newton's Principia into French.
Why it mattered. She made the energy side of the debate clear and widely read.
Émilie du Châtelet, building on Willem 's GravesandeParis
In 1722 the Dutch scientist 's Gravesande dropped brass balls into soft clay from different heights. A ball going twice as fast made a dent about four times as deep, so the effect grew with speed squared. Du Châtelet used these results in her book Institutions de physique to back Leibniz's living force.
Why it mattered. She helped show that mass times speed squared, not just mass times speed, measures what a moving body can do.
Andry, a Paris professor then in his eighties, wrote a book on preventing and correcting crooked bodies in children. He invented the word orthopédie from Greek words for straight and child. His picture of a bent young tree tied to a straight stake is still the symbol of orthopaedics.
Why it mattered. It named the medicine of bones and joints.
Frederick the Great and Johann Joachim QuantzBerlin and Potsdam, Prussia
When Frederick II became King of Prussia, his flute teacher Johann Joachim Quantz joined his court for good. Frederick reportedly played several sonatas and concertos at concerts every evening. Quantz made eleven flutes for him and added a second key to help with tuning.
Why it mattered. A royal flute player made the flute fashionable across Europe.
Robins, a military engineer, built a whirling arm to swing test shapes round in a circle and measure the air's drag on them. It is often counted as the first centrifuge-like machine; engineers later used whirling arms to test wings and propellers.
Why it mattered. Spinning things fast in a circle became a way to do experiments.
Celsius showed that melting snow always sits at the same temperature, and so does boiling water at a fixed air pressure. He split the gap into 100 steps. But he put 0 at boiling and 100 at freezing. Soon after his death in 1744 the scale was flipped the right way up.
Why it mattered. Two fixed points and 100 steps gave the world the scale most people use today.
In his Traité de dynamique, d'Alembert said the quarrel was partly about words. Measure a force by how long it acts and m v is right; measure it by how far it acts and m v² is right. Today we call these impulse and work.
Why it mattered. It pointed the way to keeping both momentum and energy.
Daniel's father Johann published his own Hydraulica, which borrowed key ideas from his son's work, and dated it 1732 so that it seemed to come first. Father and son had already fallen out after sharing a Paris Academy prize.
Why it mattered. One of the most bitter priority fights in the history of science.
Lieberkühn, a German anatomist, filled blood vessels with coloured wax and studied the gut under the microscope. His book described the villi, tiny finger-like bumps, in great detail, and the small pits between them, now called the crypts of Lieberkühn. The crypts are where new gut lining cells are made.
Why it mattered. Villi and crypts are the heart of how the small intestine absorbs food and renews itself.
Ewald Georg von Kleist; Pieter van MusschenbroekPomerania; Leiden
Two experimenters, working separately, found that a water-filled glass jar could store a large charge and release it in one painful spark. The Leyden jar became the battery of 18th-century science.
Why it mattered. For the first time, charge could be collected and let go on demand.
Clear pictures of the tabla only appear from about 1745 onwards. Historians such as James Kippen use evidence like this, not legends, to date the drum. Its shape kept changing until the early 1800s.
Why it mattered. Pictures give the best evidence we have that the tabla took shape in the 18th century.
Lind, a naval surgeon, took 12 sailors with scurvy, as alike as he could find, and gave pairs of them six different remedies. The two given oranges and lemons were almost well within a week; the others barely improved.
Why it mattered. It is one of the first planned comparisons of treatments, the seed of the fair test.
Instead of pushing a cataract aside, the French surgeon Daviel opened the eye and removed the cloudy lens. He presented his method to the Royal Academy of Surgery in 1752.
Why it mattered. Removing the lens, rather than couching it, is the basis of every cataract operation today.
Franklin argued that electricity is a single 'fluid'. A body with too much was 'positive' (plus), one with too little 'negative' (minus). The choice of which was which was a guess, and it is why conventional current flows from + to − while electrons go the other way.
Why it mattered. The signs on every battery, and the 'backwards' arrows on circuit diagrams, come from here.
Gottfried Silbermann and J.S. BachFreiberg and Potsdam, Germany
Silbermann built his first piano in 1732. Bach complained that its treble was weak and its keys were hard to play, so Silbermann improved it. On 7 May 1747 Bach visited Frederick the Great in Potsdam and played the king's Silbermann pianos; by 1749 he was even helping to sell one.
Why it mattered. Winning over the greatest keyboard player of the age helped the new instrument spread.
Nollet filled a jar with spirit of wine (alcohol and water), tied a piece of pig's bladder over the top and sank it in pure water. Over a few hours the bladder bulged outwards, and when he pricked it, liquid spurted up more than a foot. Water had got in through the bladder, but the alcohol could not get out.
Why it mattered. It is the first recorded experiment on osmosis, and it already showed the key idea: a membrane that lets water through but not everything else builds up a pressure.
Abbé Nollet tied a piece of pig's bladder over a jar of spirits of wine (alcohol) and sank it in water. After a few hours the bladder bulged outwards. When he pricked it, liquid squirted up more than a foot.
Why it mattered. It was the first recorded observation of osmosis: water moving through a thin skin towards the stronger solution.
In a paper for the Berlin Academy, Euler reasoned that the friction to start an object moving is bigger than the friction while it slides. He showed how to measure friction with an object on a ramp, and worked out the angle at which a weight starts to slide.
Why it mattered. He separated static from kinetic friction and gave us the ramp test in chapter 1.
Newton wrote his second law in words and geometry. In a paper for the Berlin Academy, Euler wrote it as equations, one for each direction, and showed they work for every tiny piece of any object, even a spinning one.
Why it mattered. This is the first appearance of F = ma in the general form students use today.
Réaumur fed a tame kite (a bird of prey) small metal tubes with holes, filled with meat. The tubes stopped the meat being crushed, yet when the bird coughed them up the meat had partly dissolved. He also had it swallow sponges on threads to collect its stomach juice.
Why it mattered. It showed that digestion is more than grinding: a juice dissolves food.
Réaumur fed a tame bird of prey (usually described as a kite or buzzard) small metal tubes with holes, filled with meat. The tubes protected the meat from being crushed, yet when the bird coughed them up the meat had partly dissolved. He also had it swallow sponges on threads to collect its stomach juice.
Why it mattered. It showed that digestion is more than grinding: a juice dissolves food.
In a medical dissertation on the odours of medicines, Linnaeus sorted smells into seven classes: aromatic, fragrant, ambrosial (musky), alliaceous (garlicky), hircine (goaty), repulsive and nauseating.
Why it mattered. It was an early attempt to organise smells like plants, and it showed how hard smells are to classify.
Franklin is said to have flown a kite in a thunderstorm and drawn sparks from a key on its wet string, showing that lightning is electricity. The details come from later accounts, and he was lucky: others were killed repeating such experiments.
Why it mattered. Lightning was proved to be electric, and Franklin's lightning rod soon protected buildings.
Quantz published a long treatise on playing the flute, called Versuch einer Anweisung die Flöte traversiere zu spielen. It covers breathing, tonguing, ornaments and good taste in music, not just the flute. Musicians still read it to learn how Baroque music was played.
Why it mattered. It is one of the most important music books of the 1700s, and it started from the flute.
Bernoulli's friend Euler turned the idea into mathematics: equations for any moving fluid without friction. He presented them to the Berlin Academy in 1752 and published them in 1757. The formula we call Bernoulli's equation, P + ½ρv² + ρgh = constant, comes out of Euler's work.
Why it mattered. Bernoulli had the insight; Euler wrote down the law in the form used today.
Black heated magnesia alba and chalk and weighed them. They lost weight by giving off a gas he called fixed air, the gas we call carbon dioxide. He later found it in the breath and in the gases from burning charcoal.
Why it mattered. Careful weighing showed that a gas could be part of a solid, and gave chemists the first product of burning.
Hahnemann was born into a family of porcelain painters. He studied medicine in Leipzig, Vienna and Erlangen, and spoke many languages, which later let him earn a living as a translator.
Why it mattered. His skill as a translator put him in front of the book that started homeopathy.
Cullen, a doctor and chemist, used an air pump to lower the pressure over a dish of ether. The ether boiled at room temperature and pulled so much heat from the water around it that the water froze. He did the experiments in Glasgow, and they were published in Edinburgh in 1756, the first documented demonstration of artificial refrigeration.
Why it mattered. It showed that a liquid boiling at low pressure soaks up heat: the trick inside every fridge's cold coils.
Lomonosov repeated Boyle's test but kept the flasks sealed. Heating metal inside them did not change the total weight; only letting air in did. He had already written to Leonhard Euler in 1748 that matter lost in one place is gained in another. His results were recorded in his notes and were little known in Western Europe.
Why it mattered. He reached the conservation of mass years before Lavoisier, though historians still debate how complete his proof was.
Cullen, a doctor and chemist, used an air pump to lower the pressure over a container of ether. The ether boiled at room temperature and pulled so much heat from its surroundings that it made a little ice. It was the first documented public demonstration of artificial refrigeration.
Why it mattered. It showed that lowering the pressure lets a liquid boil cold and soak up heat, the heart of the refrigeration cycle.
Black studied a heavy gas he called fixed air, now called carbon dioxide. Breath bubbled through lime water turned it cloudy, showing that animals breathe the gas out.
Why it mattered. It identified the biggest waste the body makes, about 1 kg a day.
Benjamin Franklin and John HadleyCambridge, England
Franklin and the chemist John Hadley kept wetting a thermometer bulb with ether and blowing on it with bellows. The reading fell from about 18 °C to about −14 °C, and a skin of ice grew on the bulb. Franklin wrote that you might freeze a man to death on a warm summer's day this way.
Why it mattered. A dramatic proof that evaporation can pull things far below freezing.
In his thesis Theoria Generationis, the German scientist Caspar Friedrich Wolff showed from chick embryos that organs such as the gut form from simple, unshaped layers. Nothing was ready-made: the body builds itself in stages, an idea called epigenesis.
Why it mattered. It replaced the tiny-person idea with the picture of development that biology still uses.
Smeaton spent seven years testing model water wheels and windmills and reported how much weight each could raise, how high, in a given time. He showed that an overshot wheel, fed from the top, does far more work than an undershot one. The Royal Society gave him its Copley Medal.
Why it mattered. Measuring weight raised times height per minute is measuring power.
Du Châtelet translated the Principia into French and added her own commentary, finishing just before she died in 1749. It was published in part in 1756 and in full in 1759.
Why it mattered. It helped Newton's ideas win over Europe, and it is still the standard French translation.
Black noticed that ice melting in a warm room stays at the same temperature for a long time, even though it keeps soaking up heat. He called this hidden heat latent heat. He also found that the same amount of heat warms different materials by different amounts, which we now call specific heat.
Why it mattered. It showed that heat and temperature are two different things.
In Theoria motus corporum solidorum seu rigidorum, Euler worked out how rigid bodies rotate. He named the moment of inertia and wrote the turning version of Newton's second law, which we now write τ = I α.
Why it mattered. It connected torque to spinning, not just balancing.
In his book on the motion of rigid bodies, Euler named the 'moment of inertia', the spinning version of mass, and showed how it governs how bodies turn, wobble and tumble.
Why it mattered. It explained flywheels, spinning tops and skaters.
A British doctor, John Zephaniah Holwell, described travelling inoculators in Bengal who scratched smallpox matter into the skin and then cared for the patient. Some writers claimed the practice was ancient, but no old Sanskrit text describing it has been found, so its age is uncertain.
Why it mattered. It shows variolation was spread across Asia before vaccines existed.
Euler worked out why sailors can hold a straining ship with a few turns of rope round a post. The force the rope can hold grows exponentially with the angle of wrap: T = T₀ × e^(μθ). Johann Eytelwein published it again in 1808.
Why it mattered. The capstan equation explains bollards, knots and belt drives.
Hewson, a surgeon and anatomist, showed the Royal Society that blood clots because of a substance in its liquid part, not because the cells stick together. He also studied the lymph vessels and the shape of red cells.
Why it mattered. He found the idea behind fibrin, and is often called the father of haematology.
Richard SalterBilston, near Wolverhampton, England
Richard Salter made the first spring balance in Britain. Hang a load on the hook, the spring stretches, and a pointer shows the weight. His family firm, George Salter and Co., went on to make spring balances for shops, homes and even steam engines.
Why it mattered. Hooke's law moved out of the lab and into kitchens and markets.
Richard SalterBilston, near Wolverhampton, England
Salter made one of the first spring balances: a spring, a hook and a pointer against a scale. Because stretch is proportional to load, the marks could be evenly spaced.
Why it mattered. Hooke's law became an everyday measuring tool, still used in markets and for luggage.
Cugnot, a French army engineer, built a three-wheeled steam wagon called a fardier to haul heavy cannons. He tested a small version in 1769 and a full-size one in 1770. It crawled along at walking pace and had to stop about every fifteen minutes to build up steam again.
Why it mattered. It is widely considered the first full-size vehicle to move under its own power, and the 1770 machine still stands in a Paris museum.
Scheele, a pharmacist, heated mercury oxide, saltpetre and other substances and collected a gas that made things burn fiercely. He called it fire air. His book describing it was held up at the printer until 1777, so others were credited first.
Why it mattered. He was probably the first to make oxygen, a reminder that discoveries often happen twice.
The pharmacist Scheele heated chemicals and collected a gas that made things burn brightly. He called it ‘fire air’. His book about it was not printed until 1777, so others published first.
Why it mattered. He was probably the first to make oxygen, which is why historians share the credit.
Priestley used a big lens to focus sunlight on red mercury oxide and collected the gas it gave off. A candle burned brilliantly in it, and a mouse lived longer in it than in ordinary air. In Sweden, Carl Wilhelm Scheele had probably made the same gas a little earlier, but published later.
Why it mattered. Oxygen is the gas your whole respiratory system exists to collect.
Priestley used a big lens to focus sunlight on red mercury oxide and collected the gas it gave off. A candle burned brilliantly in it, and a mouse lived longer in it than in ordinary air. Later he breathed some himself and said it felt light and easy.
Why it mattered. Oxygen is the gas your lungs exist to collect.
Nevil Maskelyne and Charles HuttonSchiehallion, Scotland
Maskelyne measured how much the mountain Schiehallion pulled his plumb lines sideways, using the stars as a reference. Hutton then worked out the mountain's mass and, from that, estimated that the Earth is about 4.5 times as dense as water.
Why it mattered. It was the first real measurement of the Earth's density, and so of its mass.
Priestley focused sunlight with a large lens onto red mercury calx. A gas came off in which a candle burned with a dazzling flame and a mouse lived longer than in ordinary air. He called it dephlogisticated air and told Lavoisier about it in Paris that October.
Why it mattered. Priestley found oxygen but kept the phlogiston theory; Lavoisier saw what it really meant.
Lavoisier heated tin in sealed glass vessels and weighed everything before and after. The total did not change. When he broke the seal, air rushed in, and the weight rose by exactly what the tin had gained.
Why it mattered. The metal was taking something out of the air, not losing phlogiston: the key experiment behind this box's first chapter.
So many inventors sent in machines that were supposed to run for ever that the Academy got fed up. It decided to stop examining perpetual motion machines, along with attempts to square the circle. Nobody could yet explain why such machines always fail, but experience said they did.
Why it mattered. It showed scientists already trusted that you cannot get work out of nothing, long before the law was written down.
Dobson boiled away the urine of a man with diabetes and was left with a white, sugary cake. He also found the man's blood serum tasted sweet, an early hint that the problem was sugar in the blood.
Why it mattered. It turned 'sweet urine' into chemistry: diabetes is about too much sugar.
Lavoisier, who went on to name oxygen, showed that animals use up this part of the air and breathe out carbon dioxide, just as a burning candle does. Only the oxygen mattered; the rest of the air came in and went out unchanged.
Why it mattered. It explained what breathing is really for: burning food with oxygen to release energy.
In a paper on combustion in general, Lavoisier argued that burning, rusting and breathing are all a substance joining with part of the air. He named that part oxygène, "acid maker", because he wrongly thought all acids contained it.
Why it mattered. It replaced phlogiston with the idea we still use: burning is joining with oxygen.
Johann Andreas Stein and W.A. MozartAugsburg, Germany
Mozart, then 21, visited Stein's workshop and wrote to his father about the pianos. He praised their escapement, saying that without it you cannot avoid jangling and vibration after a note. Stein's light, quick 'German' action became the Viennese piano action. Mozart's own piano, bought around 1782, was by Stein's Viennese rival Anton Walter.
Why it mattered. A good escapement lets the hammer bounce away cleanly, so the string can ring.
Late in the 1700s, makers in Italy and southern France began fitting single strings instead of pairs, and added a sixth. A guitar labelled Gaetano Vinaccia, Naples, 1779 is widely considered the earliest surviving unmodified six-string guitar. Neapolitan makers such as the Fabricatore family soon made many more.
Why it mattered. Six single strings, tuned E A D G B E, is the guitar almost everyone plays today.
The Italian priest and scientist Lazzaro Spallanzani showed that frog eggs only develop after they touch sperm-containing fluid. When he filtered the sperm out, the fluid no longer worked. He also carried out the first successful artificial insemination, in a dog.
Why it mattered. Experiments, not just looking, showed that both the egg and the sperm are needed.
The Italian priest and scientist swallowed small linen bags and pierced wooden tubes holding food, and got them back to see what had happened. He collected gastric juice and showed it could digest meat in a glass, outside the body.
Why it mattered. Digestion in a glass proved it is chemistry, not a life force or simple cooking.
René-Antoine Ferchault de Réaumur and Lazzaro SpallanzaniFrance and Pavia, Italy
In 1752 Réaumur got a pet kite, a bird, to swallow little tubes of food and cough them up half-digested. Spallanzani, an Italian priest and scientist, went further and swallowed linen bags and tubes of food himself, then looked at what was left. By 1783 he concluded digestion is chemical, done by juices, not just grinding.
Why it mattered. It turned digestion from guesswork into something you could test.
The Italian priest and scientist Spallanzani swallowed small linen bags and pierced wooden tubes holding food, and got them back to see what had happened. He collected gastric juice and showed it could digest meat in a glass outside the body, published in 1780.
Why it mattered. Digestion in a glass proved it is a chemical process, not life-force or cooking.
Christian Gottlieb KratzensteinSt Petersburg, Russia
The Imperial Academy of Sciences in St Petersburg offered a prize for explaining how we make vowel sounds. Kratzenstein won in 1780 with pipes shaped like mouths, each sounded by a free reed, that could say A, E, I, O and U. It is one of the first talking machines.
Why it mattered. It showed Europe how useful the free reed could be.
Drummers from Sidhar Khan's family moved from Delhi to Lucknow, invited by the Nawab Asaf-ud-Daula. There they played for Kathak dancers and for singers at court. Their style grew bolder and more resonant to match the dance.
Why it mattered. The Lucknow gharana showed the tabla could power dance as well as song.
In India the pankha began as a hand-held fan of palm leaf or woven bamboo. In colonial times the word came to mean a big cloth fan hung from the ceiling and swung by a servant, the punkah-wallah, who pulled a rope for hours. Several could be tied together to cool a whole courtroom or office.
Why it mattered. It was air conditioning by muscle, and it shows how much work people would do to move air.
The Indian pankha, from pankh, a bird's wing, grew into a big cloth fan hung from the ceiling of offices, courts, barracks and homes. Workers called punkah-wallahs swung it with a rope, often in day and night shifts, for very low pay; in the 1880s some earned about 3 rupees a month.
Why it mattered. It was the ceiling fan before motors, powered by the hard, often unseen labour of Indian workers.
With no instrument to measure current, Cavendish sent charge from Leyden jars through tubes of salt water and judged the strength of the shock in his own body. He found the current rose in step with the 'degree of electrification', which is Ohm's law in all but name. He never published it.
Why it mattered. The law was found once and then lost for almost a century, until James Clerk Maxwell edited Cavendish's papers in 1879.
Watt watched mill horses turn a wheel of 12 ft radius 144 times an hour, pulling with about 180 pounds-force. That came to about 32,600 foot-pounds a minute. In 1783 he and Boulton rounded it up to 33,000: one horsepower, today 745.7 W.
Why it mattered. It gave buyers a number for how fast an engine could work.
Henry Sidgier was granted a British patent for a rotating drum washer. Clothes went inside a wooden drum, and turning a handle rolled them through the soapy water. In the 1790s Edward Beetham sold many 'patent washing mills' in England.
Why it mattered. A turning drum that lifts and drops clothes is still how most of the world's washing machines work.
Giordano RiccatiTreviso, Republic of Venice (now Italy)
Riccati compared how stiff steel and brass are by making bars of each vibrate and timing their notes. He found steel about twice as stiff as brass, a ratio of 2.06 that still matches modern values, twenty-five years before Thomas Young's paper.
Why it mattered. Stiffness became something you could measure and compare, material by material.
Antoine Lavoisier and Pierre-Simon LaplaceParis, France
Measuring the heat and carbon dioxide from a guinea pig in an ice calorimeter, they argued that breathing is a slow combustion: food burns with oxygen and leaves carbon dioxide.
Why it mattered. It explained where the carbon dioxide we breathe out comes from.
Antoine Lavoisier, Marie-Anne Lavoisier, Pierre-Simon Laplace and Armand SéguinParis, France
Lavoisier showed that animals use up oxygen and breathe out carbon dioxide, just like a burning candle. With Laplace he measured the body heat of a guinea pig by how much ice it melted, and later, with Séguin, how much oxygen a person uses resting and working. Marie-Anne Lavoisier worked in the lab and drew the experiments.
Why it mattered. It explained what breathing is for: burning food with oxygen, slowly, inside the body to release energy.
Antoine Lavoisier, Pierre-Simon Laplace, Armand Séguin and Marie-Anne LavoisierParis, France
In the winter of 1782–83 Lavoisier and Laplace put a guinea pig inside a jacket of ice and measured how much ice its body heat melted. Around 1789–90 Lavoisier and Séguin measured how much oxygen a person used when resting, eating and working. Marie-Anne Lavoisier took part and drew the experiments.
Why it mattered. These were the first measurements of how fast a body burns oxygen.
Joseph-Michel and Jacques-Étienne MontgolfierAnnonay and Paris
The Montgolfier brothers, paper makers, sent up an unmanned balloon of hot air from the market square of Annonay on 4 June 1783. On 21 November, Pilâtre de Rozier and the Marquis d'Arlandes flew across Paris for about 25 minutes. Days later Jacques Charles flew a hydrogen balloon.
Why it mattered. People flew for the first time, lifted only by the difference in air density.
Lavoisier and Laplace put a guinea pig in an ice calorimeter and measured the heat it gave out and the fixed air it breathed out. Burning charcoal to make the same amount of that gas gave nearly the same heat. Breathing, they concluded, is a slow combustion.
Why it mattered. It linked the flame and the body, the idea behind this box's chapter on fat and breath.
Joseph-Michel and Jacques-Étienne Montgolfier; flown by Jean-François Pilâtre de Rozier and the Marquis d'ArlandesParis, France
The Montgolfier brothers, paper makers from Annonay, built a huge cloth and paper balloon and filled it from a fire. Pilâtre de Rozier and d'Arlandes rode it about 9 km across Paris in some 25 minutes. The brothers thought smoke held a special gas with "levity". In fact, heated air simply spreads out, so the balloon holds less of it and is lighter than the cold air around it.
Why it mattered. It was the first time people flew freely, and it made the link between heat and gas volume impossible to ignore.
Jacques Charles and Nicolas-Louis RobertParis, France
Charles filled a silk balloon with hydrogen made from iron and acid. His first, unmanned balloon came down in the village of Gonesse, where frightened villagers attacked it with pitchforks. On 1 December, Charles and Robert flew in a hydrogen balloon themselves for about two hours, watched by a huge crowd.
Why it mattered. Gas balloons turned the study of gases into something the whole of Paris cared about.
Hahnemann gave up medical practice, writing that the treatments of the day could make a doctor a danger to his patients. He supported his family by translating medical and chemistry books.
Why it mattered. His dislike of harsh treatment explains much of homeopathy's gentle approach.
Using a sensitive twisting balance, Coulomb measured the force between the poles of long magnetised needles and found it falls with the square of the distance, the same rule he found for electric charges.
Why it mattered. It gave magnetism its first mathematical law of force, the pole model this box still uses to draw field lines.
Charles-Augustin de CoulombRochefort and Paris, France
Working at the naval shipyard of Rochefort, Coulomb slid wood and metal over each other under different loads, speeds and times of contact. His prize-winning study of simple machines, published in 1785, confirmed Amontons's laws and found that sliding friction barely changes with speed.
Why it mattered. Dry friction with a constant μ is still called Coulomb friction.
Coulomb hung a light rod from a thin wire and measured how far electric charges twisted it. The twist told him the force. He found that doubling the distance between two charges makes the force four times weaker.
Why it mattered. His torsion balance showed that forces too small to feel could be measured precisely.
Chladni scattered sand on metal plates and bowed their edges. The sand danced off the vibrating parts and gathered on the still lines, the nodes, making beautiful patterns that change with each note.
Why it mattered. They made standing waves visible for the first time, and gave acoustics its founder.
Guyton de Morveau and Antoine LavoisierParis, France
In 1787 a new book of chemical names, written by Guyton de Morveau with Lavoisier and others, used the word calorique for the stuff of heat. In his famous 1789 textbook Lavoisier spread the idea: heat was a weightless fluid that flowed from hot bodies into cold ones.
Why it mattered. The caloric idea was wrong, but it gave scientists a clear picture to test, and the tests changed everything.
Charles is said to have filled balloons with different gases and warmed them all by the same amount. Each one grew by the same fraction of its size. He never wrote it up, so we only know about it because another scientist gave him the credit later.
Why it mattered. It suggested that all gases follow one rule for heat, whatever they are made of.
Marie-Anne Lavoisier translated Richard Kirwan's Essay on Phlogiston from English into French, adding notes that took its arguments apart. She kept the laboratory's records, took part in experiments and hosted scientists from across Europe.
Why it mattered. Her work spread the new chemistry, though she was rarely credited in her lifetime.
Antoine Lavoisier, with drawings by Marie-Anne LavoisierParis
Lavoisier's Traité élémentaire de chimie stated that nothing is created in any operation, of art or of nature: the same quantity of matter exists before and after. It listed 33 elements and used a new, logical naming system. Marie-Anne drew its 13 plates of apparatus. Five years later Lavoisier was guillotined in the Revolution.
Why it mattered. It is often called the first modern chemistry textbook, and it made conservation of mass the ground rule of chemistry.
Translating William Cullen's Materia Medica, Hahnemann doubted Cullen's explanation of why cinchona bark treats malaria fever. He took the bark himself while healthy and reported fever-like symptoms. Later repeats did not reliably produce the same effect.
Why it mattered. This self-test gave him the idea that "like cures like".
Abbé Georg Joseph Vogler, inspired by organ builder KirsnikRotterdam, Netherlands, and other cities
In 1788 the travelling musician Abbé Vogler met Kirsnik, an organ builder who put free reeds in organ pipes, in St Petersburg. From 1790 Vogler added free-reed stops to about 30 organs around Europe. He also built his own touring organ, the orchestrion.
Why it mattered. It carried the free reed from a curiosity into real instruments.
Galvani found that frog legs jumped when their nerves were touched with metal or sparks. He proposed "animal electricity" flowing from nerve to muscle. Alessandro Volta disagreed, and their argument led to the battery.
Why it mattered. It showed that the signal that makes a muscle contract is electrical.
Galvani found that frog legs twitched when their nerve was touched with metal or sparked with electricity. He published his idea of “animal electricity” in 1791. His rival Alessandro Volta disagreed, and their argument led to the battery.
Why it mattered. Nerves, it turned out, work with electricity, not spirits.
Galvani found that touching a frog’s nerve with metals, or with an electric spark, made its leg muscles twitch. He published his results in 1791 and argued that nerves carry a kind of animal electricity.
Why it mattered. It began the science of electricity in nerves, the basis of every spike.
Galvani found that a dissected frog's leg twitched when touched with two different metals. He believed the electricity came from the animal itself, which he called 'animal electricity'. We now know nerves really do signal with electricity.
Why it mattered. The argument over the frog's leg led straight to the battery.
Prévost argued that every object is always sending out heat, no matter how cold it is. A hot object and a cold one both radiate, but the hot one sends out more. When the two sides trade equally, their temperatures stop changing.
Why it mattered. His theory of exchanges is why we say snow in your hand is not sending you cold: your hand is simply losing more heat than it gets back.
Cowasjee and an Indian surgeon; letter signed only “B.L.”Near Pune, India; printed in London
The Gentleman's Magazine in London printed a letter about Cowasjee, a bullock driver for the British army whose nose had been cut off after he was captured by Tipu Sultan's forces. Near Pune, an Indian surgeon had given him a new nose using a flap of skin from his forehead. The method was thought to have been practised in India for centuries.
Why it mattered. This “Indian method” reached European surgeons and helped start modern plastic surgery.
Dalton, a chemist, noticed that flowers other people called pink looked blue to him. He described his colour vision to the Manchester Literary and Philosophical Society, and for a long time colour blindness was called Daltonism.
Why it mattered. It was one of the first careful scientific reports of colour vision deficiency.
Vaughan designed a carriage axle in which balls ran along a groove, so the parts rolled instead of rubbing. In 1869 a radial ball bearing designed by Jules Suriray helped James Moore win the Paris–Rouen bicycle race.
Why it mattered. Rolling instead of sliding cuts friction enormously: every fan and mixer motor depends on it.
The Scottish maker John Broadwood took over Burkat Shudi's harpsichord firm. In 1789, at the pianist Dussek's suggestion, he stretched his grand piano beyond five octaves, and by 1794 to six full octaves. English grands had a heavier action and a bigger sound than Viennese ones.
Why it mattered. Composers wrote for the notes that makers added, and makers added notes for composers.
Nannette Stein grew up in her father's workshop in Augsburg and carried it on after he died in 1792. In 1794 she moved the business to Vienna with her husband. Her firm grew to make 50 to 65 grand pianos a year, and she was a close friend of Beethoven.
Why it mattered. One of the leading piano makers of Beethoven's Vienna was a woman.
Bramah, a locksmith and inventor of an improved flush toilet, patented a press with a small pump piston and a large ram joined by water. It put Pascal's idea to work, pressing cloth, paper and metal with enormous force.
Why it mattered. It turned Pascal's principle from a thought experiment into a factory machine.
Jenner scratched cowpox from a milkmaid’s hand into the arm of eight-year-old James Phipps, then later exposed him to smallpox. The boy did not fall ill. Jenner called the method vaccination, from vacca, Latin for cow.
Why it mattered. Vaccines would go on to wipe out smallpox and drive polio out of India.
Hahnemann published his "Essay on a New Principle for Ascertaining the Curative Powers of Drugs" in a leading German medical journal, arguing that drugs should be tested on healthy people and used for similar symptoms.
Why it mattered. This is usually counted as homeopathy's founding paper.
Jenner scratched material from a cowpox sore on a milkmaid’s hand into the arm of eight-year-old James Phipps. Weeks later he exposed the boy to smallpox, and Phipps did not fall ill. Cowpox is Latin vacca, cow, which gave us the word vaccine.
Why it mattered. It was the first vaccine: a mild, related germ that trained the body to resist a deadly one.
Thompson, an American-born scientist, published an essay on chimney fireplaces. He made them shallower with angled sides, and narrowed the throat where smoke enters the chimney so the draught sped up. Many London houses were rebuilt to his plans and became smoke-free.
Why it mattered. He showed that the shape of the opening decides whether smoke goes up the flue or into the room, the same reason a hood has a narrow throat into its duct.
Pandit Ram Sahai (1780–1826)Lucknow and Benares (Varanasi)
Ram Sahai went from Benares to Lucknow as a boy to learn from Modhu Khan. At about 17 he is said to have played for the new Nawab for seven nights in a row. Back home in Benares he spent months working out a new, powerful style, which became the Benares gharana.
Why it mattered. The Benares style could accompany soft singing and thunderous dance alike, and it is still one of the most played.
Nathaniel Briggs of New Hampshire received a United States patent titled 'Clothes Washing'. On 15 December 1836 a fire at the Patent Office in Washington destroyed thousands of early patents and models, including his. Nobody today knows for sure what his machine looked like.
Why it mattered. The very first American washing machine patent is a mystery, a reminder of how much of this history was never written down or has been lost.
Rumford noticed dust inside a large thermometer rushing up and down in two opposite streams as the liquid cooled. He worked out that liquids and gases carry heat mainly by moving: warm parts rise and cool parts sink. He also found that fur and wool keep us warm by stopping air from moving.
Why it mattered. This is the idea we now call convection, the second of the three ways heat travels.
Bramah's press leaked where the ram slid through its cylinder. His young workman Maudslay is credited with a cupped leather collar that the water pressure itself pressed tighter against the ram.
Why it mattered. Without good seals no hydraulic machine can hold high pressure; the same idea is in every brake calliper.
Giovanni Battista VenturiModena (published in Paris)
Venturi measured water flowing through pipes that narrowed and widened again, and showed that the pressure drops in the narrow part. He also studied how a fast jet drags still water along beside it.
Why it mattered. His name went on every tube with a neck, from carburettors to gas burners.
Using a torsion balance designed by John Michell, Cavendish hung a 1.8 m rod with small lead balls on a thin wire and swung 158 kg lead balls close. The rod twisted by a tiny angle, which he watched with telescopes from outside the room. He found the Earth is 5.48 times as dense as water (5.45 after a slip was corrected); today's value is 5.51.
Why it mattered. His result gave the mass of the Earth and, later, the value of G.
Henry Cavendish, using John Michell's designClapham, London, England
Cavendish used a torsion balance to measure the gravity pulling small lead balls towards big ones. The force was only about 0.00000017 newtons. From it he worked out that the Earth is about 5.5 times as dense as water.
Why it mattered. It measured gravity between everyday objects for the first time and connected weight to the mass of the whole planet.
At the Munich arsenal, Rumford put a cannon barrel in water and turned a blunt drill inside it. After about two and a half hours the water boiled, and the heat seemed to keep coming for as long as the drill turned. He told the Royal Society in London that heat could not be a fluid that runs out, but must be a kind of motion.
Why it mattered. It was a big early blow against the caloric theory and pointed toward heat as energy.
Benjamin Thompson, Count RumfordMunich arsenal, Bavaria
Rumford was in charge of drilling out brass cannons. He saw that the blunt drill made heat for as long as the horses kept turning it, enough to boil water in a few hours. Heat that never runs out could not be a fluid stored in the metal, he argued. It had to come from the motion.
Why it mattered. It was strong evidence that heat is a kind of motion, not a substance.
Benjamin Thompson, Count RumfordMunich arsenal, Bavaria
Most scientists thought heat was an invisible fluid called caloric. Rumford watched brass cannons being drilled and saw that the rubbing made heat without end. He put a cannon in water, used a blunt borer, and made the water boil in about two and a half hours without any fire.
Why it mattered. Heat that never runs out cannot be a stored fluid, so it pointed to heat being a kind of motion.
Doctors of George WashingtonMount Vernon, Virginia
As George Washington lay ill with a throat infection, his doctors drained an estimated 2.4 litres of his blood in about 12 hours, around 40% of the total. He died that night. Estimates vary.
Why it mattered. Next to "heroic" treatments like this, gentle remedies that did no harm looked very attractive.
Rumford also designed closed kitchen ranges with holes in the top for pots, and a cast-iron oven called the Rumford roaster. They used far less fuel than an open hearth. By the 1850s smaller cast-iron stoves were replacing brick ones in homes.
Why it mattered. A closed stove with pot holes on top is the ancestor of the hob on your kitchen counter.
F. C. Rein started the first firm to make ear trumpets commercially, along with hearing fans and speaking tubes. In 1819 it built an acoustic throne for King John VI of Portugal, with hidden trumpets in the arms.
Why it mattered. Hearing help became something you could buy, not just a home-made horn.
Volta stacked discs of zinc and copper separated by cloth soaked in brine, and got a steady flow of electricity for the first time. He described his 'pile' in a letter to the Royal Society in London. The unit of voltage, the volt, is named after him.
Why it mattered. The first steady current: electricity could now flow, not just spark.
Kallu Khan and Miru Khan learned from Sitab Khan, a master of the Delhi gharana, and took his teaching home to their village of Ajrara. There they built longer, trickier patterns of spoken drum syllables, called bols. Their school is called the Ajrara gharana.
Why it mattered. It showed how one tradition can branch into new styles.
Herschel split sunlight into a rainbow with a prism and put thermometers in each colour. The temperature rose from violet to red, and it was even higher just past the red end, where there was no visible light at all. He called these invisible rays calorific rays.
Why it mattered. He had found infrared, the invisible light that carries heat by radiation, even across empty space.
Volta stacked discs of zinc and copper with cloth soaked in salty water between them. The pile gave a steady electric current, something no one had made before. He described it in a letter to Joseph Banks, president of the Royal Society in London, dated 20 March 1800.
Why it mattered. For the first time people could store electricity in chemicals and let it out as a steady current, just as an inverter battery does.
Hawkins, an English engineer living in Philadelphia, patented a piano with its strings running down to the floor, the keyboard raised above them and a complete iron frame. Thomas Jefferson bought one.
Why it mattered. An upright piano fits against a wall, so a piano could fit in an ordinary home.
Volta stacked discs of zinc and copper with brine-soaked cloth between them and described the 'pile' in a letter to the Royal Society in London. Unlike a Leyden jar, which empties in a spark, it pushed a steady current for as long as the chemicals lasted.
Why it mattered. Without a steady current, no one could measure how current depends on anything.
In his 1801 Bakerian lecture Young explained colours by interference: waves that meet in step add, and waves out of step cancel. By 1803 he described light passing two slits and making bright and dark bands.
Why it mattered. It was strong evidence that light is a wave, against Newton's popular idea of particles.
Dalton, a teacher who was fascinated by weather, studied how water vapour mixes into air. He found that in a mixture of gases, each gas pushes as if the others were not there. The total pressure is just the sum of the parts. The same year he showed that different gases expand alike when heated.
Why it mattered. It is why divers and doctors can work out how much oxygen is in each breath.
Smallpox vaccine lymph reached India in May 1802, carried along a chain of vaccinated people. A three-year-old girl in Bombay, Anna Dusthall, became the first person in India to be vaccinated, on 14 June 1802.
Why it mattered. Vaccination arrived in India just six years after Jenner’s experiment.
Young proposed that the eye does not need a receptor for every colour: three kinds, sensitive to different parts of the spectrum, are enough. In the 1850s Hermann von Helmholtz developed the idea further, so it is called the Young–Helmholtz theory.
Why it mattered. It is the three-cone theory of colour, confirmed by measurements more than 150 years later.
Winzler, a chemist, built a ‘thermolamp’ that heated wood to make a burnable gas. He is often credited with making the first gas stove in 1802, and his gas is reported to have heated rooms and cooked food. Like other early gas cooking, it stayed an experiment.
Why it mattered. It showed that a gas made in one place could be piped away and burned to cook.
Gay-Lussac measured carefully how gases grow when heated at a steady pressure. He found they all grow by about 1/267 of their size at 0 °C for every degree. He also said that Charles had found this about 15 years earlier, which is why we call it Charles's law.
Why it mattered. The number 267 hid a secret: cool a gas to about minus 267 °C and its volume would, in theory, shrink to nothing.
Wedgwood captured silhouettes and camera images on paper or leather treated with silver nitrate, and Davy published the results. But they couldn't stop the images darkening, so they could only be looked at by candlelight.
Why it mattered. Capturing an image wasn't the hard part. Making it permanent was.
In Éléments de statique, Poinsot showed that any set of forces on a solid body can be replaced by one force plus a 'couple': two equal, opposite forces that twist without pushing, like two hands on a steering wheel.
Why it mattered. The couple is pure torque, and it made the maths of rotation far simpler.
Jacquard's loom wove patterns by reading a chain of cards with holes punched in them. A hole meant lift this thread, no hole meant leave it. Change the cards and the same loom weaves a different pattern.
Why it mattered. Holes and no holes are a kind of 1s and 0s, and the chain of cards was a stored list of instructions.
Leslie filled a metal cube with hot water and gave each side a different surface, some shiny and some dull or blackened. All four sides were at the same temperature, yet the dull sides sent out much more heat than the shiny ones. He described this in his 1804 book on the nature of heat.
Why it mattered. It shows why shiny surfaces, like the silvered walls of a vacuum flask, are good at holding heat in.
John Gibb ran a bleaching works and needed clean water. He built a sand filter designed by the engineer Robert Thom, and sold his extra filtered water to the townspeople.
Why it mattered. It is the first recorded sand filter to supply water to the public.
Elliott patented the elliptic leaf spring: curved strips of steel stacked into an oval under a carriage. Earlier carriages had hung from leather straps.
Why it mattered. Springy steel under the body became the standard way to smooth a ride, for carriages, trains and early cars.
Hope cooled a tall jar of water around its middle and watched thermometers at the top and bottom. Above about 4 °C the cooled water sank; below it, the cold water rose. He placed the density maximum at about 39.5 °F, near today's 3.98 °C.
Why it mattered. It explains why lakes freeze from the top and life survives beneath the ice.
In a book about steam engines, the American inventor Evans described a closed machine that would boil ether in a vacuum to make ice, then squeeze the vapour back into a liquid to use again. He named all the main parts, but he never built it.
Why it mattered. It was the first detailed design for the cycle that modern fridges run on.
Bozzini built the Lichtleiter, a “light conductor”: a candle, a mirror and a set of tubes for looking into body openings. The medical faculty in Vienna dismissed it as a curiosity.
Why it mattered. It was the first attempt at an endoscope, the tool doctors now use to look inside the stomach.
Tudor shipped ice cut from New England ponds to Martinique in the Caribbean, and people laughed at the idea. By 1833 a ship packed with 180 tons of ice sailed to Calcutta, and the trade went on to reach Madras, Bombay, Hong Kong and more.
Why it mattered. Cold became something you could buy, and the world grew hungry for a way to make it anywhere.
Hahnemann first used the term, from the Greek for "similar" and "suffering", in an essay in Hufeland's Journal. He also coined "allopathy" for ordinary medicine.
Why it mattered. The name stuck, and so did the split between the two words.
Young's Course of Lectures on Natural Philosophy, from talks at the Royal Institution in 1801–1803, described a material's stiffness as a single number: stress divided by strain. His name stuck to it.
Why it mattered. Engineers could now say steel is about 200 GPa and rubber a tiny fraction of that, and design with it.
De Rivaz built an engine that burned a mix of hydrogen and oxygen, set off by an electric spark, and patented it in France in 1807. A year later he put it on a small cart. It had no compression and no crankshaft, so it was very weak.
Why it mattered. It is often called the first vehicle driven by an internal combustion engine, where the fuel burns inside the engine itself.
In his lectures on natural philosophy, Young suggested that mass times speed squared could properly be called a body's 'energy'. The word comes from ancient Greek and used to mean activity. Young was probably the first to use it in something like its modern scientific sense.
Why it mattered. It gave the idea the name we still use.
Robert Willan sorted skin diseases by how they look, such as spots, blisters or scales, and gave each a clear name with coloured pictures. His book On Cutaneous Diseases came out in parts, and its first volume was completed in 1808. Many of his names are still used.
Why it mattered. Clear names let doctors everywhere agree on what they were seeing, the start of modern dermatology.
Hahnemann set out his full system in "Organon der rationellen Heilkunde": like cures like, provings on healthy people, one remedy at a time and the smallest dose. He revised it five times.
Why it mattered. The Organon is still the core text taught in homeopathy colleges, including India's BHMS course.
Grenié built the orgue expressif, a small organ with free reeds. He showed it in 1810, though the 1911 Britannica says his first one was finished in 1812. When the player pushed more air, the reeds sounded louder, which a normal organ pipe cannot do without going out of tune.
Why it mattered. Control over the air pressure became the harmonium's special power.
Haji Vilayat Ali Khan learned from several masters and blended their ideas into a new style named after his home town. His title Haji is said to come from making the pilgrimage to Mecca several times. He is remembered for winning a tabla contest said to have lasted 15 days.
Why it mattered. It became the youngest of the six classic schools and mixed ideas from the older ones.
Amedeo Avogadro; later championed by Stanislao CannizzaroTurin, Kingdom of Sardinia (published in Paris)
Gay-Lussac had noticed in 1808 that gases react in simple volumes, like two litres of hydrogen to one of oxygen. Avogadro explained it with a bold guess: equal volumes of any gas, at the same temperature and pressure, hold the same number of particles. Almost nobody listened until Cannizzaro handed out a pamphlet at a big chemistry meeting in Karlsruhe, Germany, in 1860.
Why it mattered. It is the n in PV = nRT: it lets you count particles by measuring a gas.
Legallois removed parts of the brain in young rabbits, one layer at a time. Taking away the big upper brain did not stop breathing, but cutting a small area of the medulla, at the base of the brain, stopped it at once. He published his results in a book in 1812.
Why it mattered. He found the place where the automatic rhythm of breathing starts, even while you sleep.
Johann Nepomuk Maelzel for Ludwig van BeethovenVienna
Maelzel, the inventor who popularised the metronome, made several ear trumpets for Beethoven as the composer lost his hearing. Some fitted round his head with a metal band. They are kept at the Beethoven-Haus in Bonn.
Why it mattered. It is a famous reminder that hearing loss can happen to anyone, even the greatest musicians.
Inspired by the reports from India, surgeon Joseph Carpue rebuilt an army officer's nose with a flap of skin from the forehead. The operation took about 15 minutes, with no anaesthetic. In 1816 he published two successful cases, and the method spread across Europe.
Why it mattered. It was the first plastic surgery operation in Britain, and it came straight from Indian practice.
Coal mines were full of firedamp, methane, which exploded when miners' candles lit it. Davy wrapped the flame in fine iron gauze. The gauze soaks up heat so fast that flame can't pass through it to the gas outside.
Why it mattered. It saved many lives, and showed that a flame needs heat as well as fuel and oxygen.
Laennec did not want to press his ear to a young woman’s chest, so he rolled paper into a tube and listened through it. He heard the heart more clearly than ever, and soon made wooden tubes. In 1819 he published a book linking the sounds of the chest to lung diseases.
Why it mattered. Doctors could now listen to the lungs, which they still do every day.
Laennec felt it would be improper to press his ear to a young woman's chest. He rolled some paper into a tube, put one end on her chest, and heard her heart more clearly than ever. He then made wooden tubes and wrote a book in 1819 linking chest sounds to diseases.
Why it mattered. Doctors could now listen to the heart's valves closing without cutting anyone open.
Napoleon's Academy offered a prize for the mathematics of Chladni's patterns. Sophie Germain, a self-taught mathematician barred from universities as a woman, entered three times and won in 1816, the first woman to win a prize from the Paris Academy of Sciences.
Why it mattered. Her work began the theory of elastic plates, still used to design everything from loudspeakers to bridges.
Laplace realised that squeezed air in a sound wave warms up and stretched air cools, too fast for the heat to escape. Adding that effect raised Newton's speed of sound to match the measured value, about 340 m/s.
Why it mattered. It closed a 130-year puzzle and is why the box uses v = 331 √(1 + T/273) m/s.
Bohnenberger built a heavy spinning sphere in a set of rings, which he simply called 'the Machine'. However its frame was tipped, the spinning ball kept its axis steady.
Why it mattered. The first instrument built to show how spin resists torque.
Ludwig van Beethoven, Érard and BroadwoodParis, London and Vienna
In October 1803 Beethoven got a grand piano from the Érard firm in Paris and loved it at first. In December 1817 Thomas Broadwood sent him a six-octave grand from London. It arrived in Vienna about seven months later, and Beethoven kept it for the rest of his life.
Why it mattered. Beethoven's music pushed pianos to be louder and wider, and makers followed.
Drais rode his Laufmaschine, a wooden frame with two in-line wheels and a steerable front, from Mannheim to a coaching inn and back, about 13 km in a little over an hour: faster than walking. Some historians link the invention to the “Year Without a Summer” of 1816, when failed harvests made horses costly to feed, but the link is debated.
Why it mattered. It proved that you can balance on two wheels in a line as long as you keep moving and can steer.
The obstetrician Blundell, desperate to save women bleeding after childbirth, gave the first human-to-human blood transfusion in 1818. That patient died, but in 1825 a mother bleeding after birth recovered. Nobody yet knew why some transfusions went badly wrong.
Why it mattered. It started the long road to safe transfusion.
Laennec, who also invented the stethoscope, described the scarred, lumpy liver of a former soldier in a footnote to his famous book on listening to the chest. He called the disease cirrhosis, from the Greek kirrhos, meaning tawny yellow, the colour of the lumps. Earlier doctors had described it, but his name stuck.
Why it mattered. Cirrhosis, the end result of long liver damage, finally had a name that doctors everywhere used.
The Madras Eye Infirmary opened in 1819, the second eye hospital in the world after Moorfields in London (1805). It became the Regional Institute of Ophthalmology in Egmore, Chennai.
Why it mattered. It began a long tradition of eye care and training in India.
London coachmaker Denis Johnson built an improved version, the “pedestrian curricle”. Fashionable young men rode “hobby horses” or “dandy horses” until the fad faded, partly because riders on pavements annoyed pedestrians.
Why it mattered. The first bike boom, and the first complaints about cyclists.
During a lecture, Ørsted saw a compass needle swing when a current from a battery flowed in a nearby wire. Electricity and magnetism were linked (see MagnetismClear).
Why it mattered. The discovery behind every electric motor and meter needle.
Within weeks of hearing of Ørsted's result, Ampère showed that two parallel wires carrying current attract or repel each other. He called the flow an electric 'current', worked out the law of the force between currents, and studied it until 1827. The unit of current, the ampere, honours him.
Why it mattered. Current became something you could measure by its force.
Ørsted saw a compass needle swing when current flowed in a wire above it, reportedly first during a lecture in the spring of 1820. He published the result in a short Latin paper that summer. The needle turned across the wire, showing the field goes round it.
Why it mattered. It joined electricity and magnetism for the first time and set off a burst of discoveries within months.
Within weeks of hearing of Ørsted's result, Ampère showed that two parallel wires attract when their currents flow the same way and repel when opposite. He suggested that all magnetism comes from tiny circulating currents. The unit of current, the ampere, is named after him.
Why it mattered. It showed that magnets and coils of current are the same kind of thing.
Ørsted showed that a wire carrying current swings a nearby compass needle. He described it in a short Latin pamphlet dated 21 July 1820 and posted it to scientists all over Europe.
Why it mattered. Electricity could make magnetism. Everyone now asked: can magnetism make electricity?
Ørsted showed that a wire carrying current swings a nearby compass needle, and published it in July 1820. Within months others turned the effect into the galvanometer: the stronger the current, the further the needle turns.
Why it mattered. It gave scientists the first way to measure current, which Ohm would use.
Faraday hung a wire so its end dipped into a bowl of mercury round a standing magnet. When current flowed, the wire swept round and round the magnet. It was the first device to turn electric current into continuous motion.
Why it mattered. Every electric motor, from a mixer grinder to an electric car, grows from this experiment.
Prony clamped a friction band round a drum on an engine's shaft and fixed a lever arm to it. The force on the scale at the arm's end, times the arm's length, gives the engine's torque.
Why it mattered. For the first time an engine's turning strength could be measured, not guessed.
Thomas Johann SeebeckBerlin, Prussia (today Germany)
Seebeck noticed that a compass needle moved near a loop of two different metals when one of the joins was heated. Heat was making an electric current. A pair of metals joined like this is now called a thermocouple.
Why it mattered. Much later, a thermocouple sitting in a gas flame became the safety device that shuts the gas off if the flame goes out.
Faraday made a wire carrying current spin round and round a magnet standing in a cup of mercury. It was the first time electricity had been turned into steady motion.
Why it mattered. It is the ancestor of every electric motor, and it set Faraday thinking about forces curling around wires.
Sébastien and Pierre ÉrardLondon, England, and Paris, France
Sébastien Érard's 'double escapement' was patented in London in 1821 by his nephew Pierre. A repetition lever catches the hammer part-way, so you can play the same note again before the key has fully risen.
Why it mattered. Almost every grand piano action today is based on this design, which makes fast repeated notes possible.
Davy found that a wire conducts less the longer it is and more the thicker it is, and that metals conduct worse as they get hotter. He ranked silver first, then copper.
Why it mattered. These are the rules behind R = ρL ÷ A, and behind the hot bulb filament of chapter 5.
Seebeck found that a loop of two different metals makes a current when one junction is hotter than the other. The push depends only on the temperature difference, so it is very steady.
Why it mattered. Ohm's first batteries drifted too much. A thermocouple with one end in ice and one in boiling water gave him a push he could trust.
A young farmer who had healed his own broken ribs with wet bandages began treating neighbours with cold water. In 1822 he rebuilt his father's house as a spa: cold baths, wet wraps, fresh air, walks and plain food.
Why it mattered. It started the European 'water cure', the root of the hip baths and packs used in naturopathy today.
Charles Babbage designed a Difference Engine to print mathematical tables without human mistakes. By 1837 he had designed something far bigger: the Analytical Engine, with a 'store' for numbers and a 'mill' to work on them, fed by Jacquard-style punched cards. Neither was finished in his lifetime.
Why it mattered. The store and the mill are the memory and the processor of every computer since.
Charles Bell and François MagendieLondon and Paris
Bell suggested in 1811, and Magendie proved in 1822, that the roots at the back of the spinal cord carry sensations in and the roots at the front carry commands out to the muscles.
Why it mattered. It is the wiring plan of every reflex.
Alexis St. Martin and William BeaumontMackinac Island, Michigan
A musket went off by accident and wounded Alexis St. Martin, a young French-Canadian fur trader. The army surgeon William Beaumont saved him, but the wound healed with an opening from the stomach to the skin. From 1825 to 1833 Beaumont dangled food on silk threads through it and drew off gastric juice, and in 1833 he published his results.
Why it mattered. For the first time a living human stomach could be watched at work, though St. Martin, a poor and dependent patient, had little real choice.
Alexis St. Martin and William BeaumontMackinac Island, Michigan
A musket went off by accident at close range and wounded Alexis St. Martin, a young French-Canadian fur trader. The army surgeon William Beaumont saved his life, but the wound healed with a permanent opening, a fistula, from his stomach to the skin.
Why it mattered. For the first time, a living human stomach could be watched at work.
Fourier worked out how heat creeps through solids: it flows from hot to cold, faster when the temperature changes steeply and faster in some materials than others. He first presented this work in 1807 and published his full book, The Analytical Theory of Heat, in 1822. To solve his equations he invented Fourier series, which are now used everywhere from music to phones.
Why it mattered. Fourier's law is still the rule engineers use for conduction, the first of the three ways heat moves.
In a memoir read to the French Academy of Sciences, Cauchy defined stress: the forces acting across any surface inside a solid. He built the full theory of linear elasticity on it, Hooke's law in three dimensions.
Why it mattered. It is the maths behind every bridge, building and aircraft checked by engineers today.
Snell's law says where light goes, but not how much of it reflects instead. Fresnel, treating light as a sideways-wobbling wave, wrote equations for how much light is reflected and how much passes through at each angle, for each direction of wobble.
Why it mattered. His equations explain why a window is also a faint mirror, and why polarising sunglasses cut the glare off water.
Faraday put gases such as chlorine under high pressure until they turned into liquids, and went on to liquefy several more, including ammonia. When the pressure was released, the liquid boiled back into a gas and grew cold.
Why it mattered. Squeeze to make a liquid, release to make cold: that is what an air conditioner's compressor and valve still do.
The English doctor and chemist Prout analysed stomach contents and showed that the acid in them is hydrochloric acid, the same acid chemists made from sea salt.
Why it mattered. It named the stomach’s strongest weapon and explained its very low pH.
The English doctor and chemist Prout analysed stomach contents from animals and showed that the acid is hydrochloric acid, the same acid chemists made from sea salt. He presented the paper to the Royal Society in December 1823.
Why it mattered. It named the stomach’s strongest weapon.
The Royal Navy's ships were covered in copper that slowly corroded in seawater. Davy showed that fixing a more reactive metal to the copper made that metal corrode instead, and he tested it on HMS Samarang.
Why it mattered. The same trick protects geyser tanks today: a magnesium ‘sacrificial anode’ rod slowly wears away so the steel tank does not rust.
Carnot asked how much work a steam engine could possibly get from its fuel. He found a limit set by how hot and how cold its two ends are, so no heat engine can turn all its heat into work.
Why it mattered. It explains why a petrol engine is only about 30% efficient.
Fourier calculated that a planet as far from the Sun as Earth should be much colder than it is. He suggested the air might act a little like the glass panes of a heat box made by the Swiss scientist Saussure, letting sunlight in but holding heat back. It was an early, rough version of what we now call the greenhouse effect.
Why it mattered. It connected radiation to the temperature of a whole planet for the first time.
A young French engineer wrote a short book called Reflections on the Motive Power of Fire. He imagined a perfect engine and showed that the work it can give depends only on how hot its hot side is and how cold its cold side is. Few people read it at the time, and Carnot died of cholera in 1832.
Why it mattered. It set a limit on every engine ever built, and it became the seed of the second law.
Carnot, a 28-year-old army engineer, wrote a short book asking how much useful work a steam engine can get out of heat. He showed that an engine works because heat flows from something hot to something cold, and that there is a best possible efficiency. He still believed in caloric, and only 600 copies were printed.
Why it mattered. His ideas became the starting point for thermodynamics, the science of heat and energy.
William Beaumont and Alexis St. MartinMackinac Island, Michigan, USA
Alexis St. Martin, a French-Canadian fur trader, was shot in the stomach by accident, and the army surgeon William Beaumont saved him. The wound healed with a permanent hole into the stomach. Beaumont dangled food on strings through the hole and drew out digestive juice, and in 1833 published what he learned.
Why it mattered. It proved in a living person that digestion is done by chemical juices, and showed how food leaves the stomach for the intestine.
Sturgeon varnished a horseshoe of iron, wound about 18 turns of bare copper wire round it and connected a single battery cell. The 200 g magnet held up about 4 kg of iron, and let go the moment the current stopped. The Society of Arts gave him a silver medal.
Why it mattered. It was the first magnet you could switch on and off, the ancestor of cranes, relays, bells and MRI magnets.
Babcock patented a complete iron frame cast in one piece for the square piano. Wood warps and moves with heat and damp, but iron could hold the strings' huge pull steady.
Why it mattered. Iron let makers use thicker, tighter strings for a bigger sound, and all modern pianos use a one-piece metal frame.
Ohm taught mathematics and physics at the Jesuit Gymnasium in Cologne. In his spare time he measured how the magnetic effect of a current weakens as the wire gets longer, and published his first paper on it in 1825.
Why it mattered. He was an outsider with a school lab, not a university professor.
The French physician Henri Dutrochet studied how water moves into living tissues and through membranes. He called the inward flow endosmose and the outward flow exosmose, from Greek words for pushing. He built simple osmometers, tubes closed by a membrane, to watch liquid climb.
Why it mattered. His words gave us the name osmosis, and he suspected it was central to how plants and animals move water.
Sharp patented a gas stove and went on to open a gas stove factory in 1836. The Science Museum in London keeps a sheet-iron gas cooker of his design, made around 1845 to 1855.
Why it mattered. It is widely seen as the first commercial gas cooker, the great-grandparent of the Indian gas hob.
The Viennese maker Conrad Graf lent Beethoven a 6½-octave piano. From the note D upwards it had four strings for each key, not three, to make it louder for the deaf composer. It is now at the Beethoven-Haus in Bonn.
Why it mattered. More strings per note means more sound, which is why modern pianos use up to three.
Using a bismuth–copper thermocouple as a steady source and a torsion galvanometer as his meter, Ohm tested wires of different lengths. His readings fitted a simple rule, x = a ÷ (b + l): the current falls as the wire's length l is added to the circuit's own resistance b.
Why it mattered. It is Ohm's law in the form 'current = push ÷ total resistance'.
Karl Ernst von BaerKönigsberg, Prussia (now Kaliningrad, Russia)
Karl Ernst von Baer opened a follicle from a dog's ovary and found a tiny yellowish speck floating inside it. It was the real egg, far smaller than de Graaf's bubble. He published the discovery in a short Latin book.
Why it mattered. It settled a 150-year-old question: mammals, including humans, do begin from a single egg cell.
Bright linked three things in his patients: swelling of the body, protein in the urine (it thickened when heated in a spoon) and hard, damaged kidneys seen after death. For a century, kidney disease of this kind was called Bright's disease.
Why it mattered. It was the first time a disease was clearly tied to the kidneys by testing urine at the bedside.
Jean-Pierre Duvelleroy opened a fan shop in Paris in 1827. His son Jules later handed out leaflets claiming that women used fans to send coded messages, such as fanning slowly to say “I am married”. Historians now think this language was invented in the 1800s to sell more fans.
Why it mattered. It is a reminder that a good story can travel further than the truth.
From an upstairs window, Niépce photographed the rooftops of his estate on a pewter plate coated with bitumen, which hardens in light. The exposure lasted at least eight hours, and probably several days, which is why sunlight falls on both sides of the buildings. He called the process heliography.
Why it mattered. It's the first camera image that still exists. You can see it at the Harry Ransom Center in Austin, Texas.
Ohm published his theory as a book, The Galvanic Circuit Investigated Mathematically, modelled on Fourier's mathematics of heat flow. It was coldly received. One critic called it a web of naked fancies, and Ohm left Cologne for years of poorly paid work.
Why it mattered. A correct law can be ignored when it arrives as maths from an unknown teacher.
Hahnemann published "The Chronic Diseases", proposing that long-lasting illness comes from deep underlying "miasms". He also moved towards higher dilutions such as 30C.
Why it mattered. Miasm theory and high potencies became central to classical homeopathy.
Wöhler heated ammonium cyanate, a salt made from non-living chemicals, and got urea, a substance until then made only by living bodies. It surprised even him.
Why it mattered. It helped end the belief that the chemistry of life follows special rules.
Wöhler made urea, the main waste in urine, from chemicals that had nothing to do with living things. Urea is made by the liver from spare protein and removed by the kidneys.
Why it mattered. It helped show that the body's chemistry follows the same rules as any other chemistry.
Honigberger, a doctor from Transylvania, reached Lahore in 1829 and later returned at Maharaja Ranjit Singh's request. Accounts say he treated the Maharaja with a homeopathic remedy around 1839. Details come mostly from his own memoir.
Why it mattered. He is usually named as the person who brought homeopathy to the Indian subcontinent.
In Du calcul de l'effet des machines, Coriolis called force times distance moved 'travail', work. He also put the half into ½ m v², showing that the work done on a body equals the change in its energy of motion. He even proposed a unit, the dynamode, 1,000 kilogram-metres, which never caught on.
Why it mattered. Work became a precise, measurable quantity for engineers.
Teaching engineers and workers at Metz, Poncelet used 'mechanical work' as the key idea for judging machines, independently of Coriolis. His Introduction à la mécanique industrielle came out in 1829, and he also designed better water wheels.
Why it mattered. He made work the everyday language of engineering.
James Simpson, Chelsea Waterworks CompanyLondon, England
The engineer James Simpson built slow sand filter beds for the Chelsea Waterworks Company. River water trickled slowly down through sand and gravel, which caught dirt and, as we now know, many germs.
Why it mattered. It is often called the first treated public water supply in the world.
In his book on calculating what machines do, Coriolis defined 'work' as a force times the distance it moves something. He put a half in front of Leibniz's living force, giving ½mv², so that the work done on a body exactly equals the energy of motion it gains.
Why it mattered. Engineers finally had a clean way to count energy going into and out of machines.
When cholera swept Europe, homeopathic hospitals reported fewer deaths than hospitals using bleeding and purges. Historians note the records are hard to compare, and avoiding harmful treatment may explain much of the difference.
Why it mattered. The reports helped homeopathy spread fast across Europe and to India.
Faraday found that a changing magnetic field drives a current in a coil: electromagnetic induction. Every generator and transformer since depends on it (see FaradayClear).
Why it mattered. It made electricity something power stations could produce in bulk.
Faraday wound two coils of wire around an iron ring. When he switched the current in one coil on or off, a current jumped into the other coil for a moment. Only a changing current could do this.
Why it mattered. This is how a transformer works, and a home inverter still uses one to lift the battery's low voltage up to mains voltage.
Faraday wound two coils of wire on opposite sides of an iron ring. When he connected a battery to one coil, a meter on the other coil flicked, then fell back to zero. It flicked again, the other way, when he disconnected it.
Why it mattered. A current appears only while the magnetism is changing. That is Faraday's law, and the ring was the first transformer.
Faraday pushed a bar magnet in and out of a coil and the meter jumped every time it moved. On 28 October he spun a copper disc between the poles of a big magnet and got a steady current from it. He read his results to the Royal Society on 24 November 1831.
Why it mattered. The Faraday disc was the first electric generator: motion in, electricity out.
Clara Wieck, later Schumann, gave concerts for 61 years, and more than 1,300 of her concert programmes survive. She played from memory at 13, which reviewers found remarkable, and helped make that the normal way to give a piano recital.
Why it mattered. Star pianists like her made the piano the centre of concert life.
Gauss worked out how to measure the strength of the Earth's field in absolute units, using a swinging magnet and a fixed one. With Wilhelm Weber he set up a network of observatories to record the field at the same moments. The old unit of field, the gauss (1/10,000 of a tesla), is named after him.
Why it mattered. It turned the Earth's field into something you could measure and compare around the world.
In 1831 the Munich flautist and goldsmith Theobald Boehm heard the English player Charles Nicholson in London, whose flute had extra large holes and a huge sound. The next year Boehm built a new conical flute with holes placed for good tuning, not for easy reach. Rings and linked keys let nine fingers open and close all the holes.
Why it mattered. It put the holes where the physics wanted them and let a clever mechanism deal with the fingers.
During a cholera epidemic, Kitty Wilkinson, an Irish migrant and labourer's wife, had the only boiler in her neighbourhood. She let neighbours wash their clothes and bedding in her home for a penny a week and showed them how to use chloride of lime. Ten years later, in 1842, a public baths and wash house opened on Upper Frederick Street in Liverpool, and she became its superintendent in 1846.
Why it mattered. Hot water and clean clothes can stop disease, and her work helped start the public wash house movement in Britain.
Henry, a teacher at the Albany Academy, built some of the strongest electromagnets in the world. He saw induction on his own, and also self-induction, where a coil pushes back against changes in its own current. Faraday published first, so Faraday got the credit.
Why it mattered. The unit of inductance, the henry, was named after him in 1893.
Pixii, an instrument maker, spun a horseshoe magnet past two coils with a hand crank. It made a current that flipped back and forth, so a switch called a commutator was added to make it flow one way.
Why it mattered. It was the first dynamo, the kind of machine that would later light cities.
Joseph Plateau (and, separately, Simon Stampfer)Ghent, Belgium, and Vienna, Austria
Plateau put a ring of drawings on a slotted disc. Spin it in front of a mirror, look through the slits, and the figures move. Stampfer made a similar stroboscopic disc in Vienna at about the same time.
Why it mattered. It proved that a cycle of slightly different drawings, glimpsed one at a time, looks like motion.
Joseph Plateau; Simon StampferBrussels, Belgium and Vienna, Austria
Plateau's phenakistiscope was a disc of drawings with slits round the edge. Spin it in front of a mirror, look through the slits, and the drawings seem to move. Stampfer made a similar disc in Vienna at almost the same time.
Why it mattered. It proved that a quick series of still pictures, glimpsed one at a time, looks like motion.
Kiernan, an Irish-born anatomist, studied pig livers under the microscope. He saw that they are built from many small units, lobules, each roughly six-sided with a vein running through its middle and vessels at its corners. He published his work in the Philosophical Transactions of the Royal Society.
Why it mattered. The lobule is still how students learn the liver's basic building block.
William BeaumontFort Niagara, Plattsburgh and other posts
Over eight years Beaumont dangled pieces of food on silk threads into St. Martin’s stomach, pulled them out to see how far they had digested, and drew off gastric juice to digest food in jars. In 1833 he published Experiments and Observations on the Gastric Juice.
Why it mattered. It proved gastric juice digests food chemically and that the stomach churns, and it became a classic of physiology.
C. F. Martin, a guitar maker from Markneukirchen in Saxony, arrived in New York in 1833 and opened a small shop. In 1839 the company moved to Nazareth, Pennsylvania, where it still makes guitars today. It is still run by the Martin family.
Why it mattered. Martin went on to shape the American steel-string guitar more than any other maker.
Tudor began shipping ice cut from New England ponds to the Caribbean in 1806, and people laughed at the idea. In 1833 the ship Tuscany carried about 180 tons of ice to Calcutta, and around 100 tons survived the long voyage and sold at a profit. Calcutta built a stone ice house to store more.
Why it mattered. Cold became something you could buy, and the world grew hungry for a way to make it anywhere.
Thomas Graham measured how fast different gases leak and mix through porous plugs. Lighter gases were quicker: the rate went as one over the square root of the gas's density. We still call it Graham's law.
Why it mattered. It was one of the first measurements showing that diffusion follows simple rules set by the molecules themselves.
Horner described a drum with slits in its side and a strip of drawings inside, which he called the daedaleum. Several people could watch at once. It was sold as a toy from the 1860s under the name zoetrope.
Why it mattered. The slits work like a camera's shutter: you see one picture, then darkness, then the next.
Weber touched people's skin with the two tips of a compass and asked if they felt one point or two. On the fingertips and tongue, points a few millimetres apart felt separate, but on the back they had to be several centimetres apart. He published this in De Tactu (On Touch) in 1834.
Why it mattered. It showed that some patches of skin are packed with far more touch sensors than others.
In a book on chemistry and weather, the doctor and chemist William Prout used a common fireplace to explain that heat moves in three ways. He coined the word convection for heat carried along by a moving liquid or gas, like warm air rising up a chimney.
Why it mattered. An air fryer is a forced convection machine, so it runs on the idea Prout named.
Perkins, an American inventor living in London, patented a closed machine that evaporated a liquid to make cold, then pumped the vapour back into a liquid to use again with no waste. His prototype worked, but it never sold.
Why it mattered. Evaporate, compress, condense, repeat: this closed loop is the cycle inside almost every fridge today.
Lenz worked out which way an induced current flows: always so that its own magnetism fights the change that made it. Push a magnet towards a coil and the coil pushes back.
Why it mattered. Lenz's law is the minus sign in Faraday's law, and the reason a generator gets harder to turn when it powers something.
Clapeyron, an engineer who had taught in St Petersburg and built early French railways, was explaining Sadi Carnot's ideas about steam engines. To do it, he joined Boyle's law and Gay-Lussac's law into one equation, pv = R(267 + t), and drew engine cycles as loops on a pressure against volume graph. That graph is still used for every engine today.
Why it mattered. It is the ideal gas law almost as we write it now.
Perkins, an American inventor living in London, patented a closed machine that evaporated a liquid to make cold, then pumped the vapour back into a liquid to use again with no waste. His prototype worked, but it never sold.
Why it mattered. Evaporate, compress, condense, repeat: this closed loop is the cycle inside almost every fridge and air conditioner today.
Clapeyron rewrote Carnot's ideas in mathematics. He drew the engine's cycle as a closed loop on a graph of pressure against volume, and the area inside the loop is the work done. That is how Carnot's forgotten book reached Kelvin and Clausius.
Why it mattered. The pressure-volume diagram is still how engineers picture engines today.
The Native Medical Institution (1822) had taught Ayurveda at the Sanskrit College and Unani at the Madrasa alongside Western medicine. A government order ended these classes, and the new Medical College taught only Western medicine.
Why it mattered. For the next century Ayurveda survived outside official support, in families, pathshalas and pharmacies.
Deep in the skin sit tiny capsules made of many layers, like an onion, wrapped around a nerve ending. Abraham Vater in Germany reported them in 1741, but they were forgotten until Filippo Pacini found them again in 1835. They respond to vibration and pressure.
Why it mattered. They were among the first touch sensors ever found in the skin.
Studying machines with turning parts, Coriolis showed that anyone describing motion from a rotating frame must add two extra terms: the centrifugal one, and a sideways one that grows with speed. The sideways one now carries his name.
Why it mattered. It explains why winds and cyclones curve on the turning Earth.
Schwann found a substance in gastric juice, different from the acid, that breaks down egg white and meat. He named it pepsin, from the Greek word for digestion. It was one of the first enzymes ever described.
Why it mattered. It showed that molecular “scissors”, not acid alone, do the cutting.
Schwann found a substance in gastric juice, different from the acid, that breaks down egg white and meat. He named it pepsin, from the Greek word for digestion. It was one of the first enzymes ever described.
Why it mattered. It showed that the acid has a partner that does much of the protein cutting.
Thomas Drummond; Goldsworthy GurneyCovent Garden Theatre, London
A flame of oxygen and hydrogen heats a block of quicklime until it glows white hot. Gurney found the effect in the 1820s and Drummond built a working lamp in 1826. In 1837 limelight was first used indoors on a theatre stage, at Covent Garden, to pick out a single performer.
Why it mattered. It was the first bright, aimable stage light, the grandparent of every spotlight.
Richard Salter's nephews, trading as George Salter & Co., patented the spring balance. They also used spring balances on steam locomotives to hold safety valves shut, in place of dead weights that bounced.
Why it mattered. A calibrated spring held back a precise force, a job springs still do in valves everywhere.
Daguerre photographed the busy Boulevard du Temple. The exposure was so long that moving traffic vanished, except a man having his boots polished, who stood still long enough to appear.
Why it mattered. It shows why exposure time mattered: anything that moved simply disappeared.
About 1,500 patients arrived in a single year, among them a duke, princes and counts, and 120 doctors came to study the method. Priessnitz had received an official licence the year before.
Why it mattered. Water cure became a fashion across Europe and spread to Britain and America.
Macmillan, a blacksmith, is said to have built a two-wheeler driven by treadles and rods to the rear wheel. The evidence is thin and historians still argue about it.
Why it mattered. A reminder that ‘who was first’ is often uncertain.
The French government bought Daguerre's process and published it for anyone to use. A daguerreotype was a one-off, astonishingly detailed image on a polished silver-coated copper plate, exposed for several minutes.
Why it mattered. Photography spread around the world within months. 19 August is still World Photography Day.
Herschel popularised “photography” (Greek for “drawing with light”) and later “negative” and “positive”. He also showed that sodium thiosulfate, “hypo”, fixes an image so it stops reacting to light.
Why it mattered. Hypo solved the problem that defeated Wedgwood.
Poiseuille, a doctor who had already measured blood pressure with a mercury gauge, timed water flowing through fine glass tubes. He found the flow depends on the radius to the fourth power: halve the width and only a sixteenth gets through. Gotthilf Hagen found the same rule in Germany in 1839.
Why it mattered. It explains why tiny arterioles control where your blood goes.
Debain patented a keyboard instrument with free reeds and foot-pumped bellows and called it the harmonium. He put several sets of reeds with different tone colours on one keyboard, chosen with stops. The 1911 Britannica and most sources give 1840 for the patent, though a few say 1842.
Why it mattered. Almost every reed organ made afterwards follows his basic plan.
Petzval calculated a portrait lens with an aperture of about f/3.6, many times brighter than the lenses on early daguerreotype cameras. Voigtländer built it into a camera in 1841.
Why it mattered. Exposures dropped to under a minute, and the portrait studio business was born.
Joule, a brewer's son, measured the heat from wires carrying current. He found it was proportional to the resistance times the square of the current: I² × R. He sent the work to the Royal Society in 1840 and published it in full in 1841.
Why it mattered. Joule's law is Ohm's law's partner: it explains every heater, fuse and warm cable.
Colaba Observatory, later directed by Nanabhoy MoosColaba, Bombay (Mumbai)
Regular magnetic observations began at Colaba in Bombay in 1841. In 1904 electric trams began to disturb the readings, so the observatory moved across the harbour to Alibag, where it still runs. Its first Indian director, Nanabhoy Moos, published two huge volumes of its records in 1910.
Why it mattered. Colaba–Alibag is one of the world's longest-running magnetic observatories.
The young Joule dipped wires in water and passed electric currents through them for half an hour at a time. He found the heat made grows with the wire's resistance and with the square of the current. This is Joule heating, the same effect that warms the element in an electric water heater.
Why it mattered. It showed electricity turns into heat by a precise rule, one more sign that different forms of energy are linked.
The Royal Society awarded Ohm its Copley Medal, then its highest prize, and made him a foreign member the next year. By then physicists in Britain and elsewhere had confirmed his law.
Why it mattered. Fourteen years after the book, Ohm's law was mainstream science.
Bowman showed that each glomerulus sits inside a cup that is the blind end of a tubule, so blood vessels and the urine tube meet there. He suggested that water leaves the blood in the glomerulus. The cup is named after him.
Why it mattered. It revealed the basic plan of the nephron: a filter joined to a tube.
To light up a lecture on water jets, Colladon shone sunlight into a tank so that it came out with the stream. The light stayed inside the curving jet, bouncing off its inner surface, and lit up the spot where the water landed. John Tyndall showed a similar jet in London in 1854 and made it famous.
Why it mattered. It was the first light guide, the ancestor of every optical fibre.
Doppler proposed that a wave's frequency depends on how its source and listener move: higher when approaching, lower when moving apart. In 1845 C. H. D. Buys Ballot tested it in the Netherlands with musicians playing a steady note on a moving train.
Why it mattered. The Doppler effect now measures blood flow, weather and the expansion of the universe.
Wornum patented a small upright in 1811 and a taller cottage piano by 1813. In 1826 and 1842 he patented actions for uprights, including a new way to work the dampers and springs to return the hammers.
Why it mattered. His design is the ancestor of the action inside most upright pianos.
Julius Robert MayerVoyage to the Dutch East Indies, then Heilbronn
In 1840 Mayer sailed to Java as a ship's doctor. When he bled sick sailors in the tropics, their vein blood was surprisingly bright red, and he reasoned that the body burns less food to stay warm in a hot place. Back home he argued that heat and motion are two forms of the same thing, and in 1842 estimated how much work equals a given amount of heat.
Why it mattered. He was the first to state the equivalence of heat and work as a general law of nature.
Hahnemann died aged 88, after years of practice in Paris with his second wife, Mélanie d'Hervilly. His 6th edition of the Organon, finished in 1842, stayed unpublished.
Why it mattered. By then homeopathy had followers across Europe, the Americas and Asia.
Ada Lovelace translated an article about the Analytical Engine and added notes three times longer than the article. Her Note G set out, step by step, how the engine could calculate Bernoulli numbers. It is widely called the first published computer program.
Why it mattered. She also saw that such a machine could work with symbols and even music, not just numbers.
Scottish clockmaker Alexander Bain patented a way to copy a pattern over telegraph wires. Two pendulums, kept in step by clocks, swept a probe across metal pins line by line, and the receiver marked paper soaked in chemicals wherever current flowed.
Why it mattered. It already had the two big fax ideas: scan line by line, and keep both ends in step. His machines were never truly synchronised, so the copies were poor.
John Turnbull patented a 'Clothes Washer With Wringer Rolls', a washer joined to a pair of rollers that squeezed water out of the clothes. Mangles and wringers like this became a common sight in Victorian homes, and in 1862 Richard Lansdale of Manchester showed a rotary washer with wringing rollers at the London Exhibition.
Why it mattered. Getting water out is half the job, and it is what today's fast spin does without any rollers.
Babcock worked as foreman for Chickering's firm. In 1843 Chickering patented the first full iron frame for a grand piano. By his death in 1853 the company had built more than 12,000 pianos.
Why it mattered. Iron-framed grands could fill a large hall with sound.
Charles Wheatstone, after Samuel Hunter ChristieLondon, England
Christie devised it in 1833; Wheatstone improved it and made it famous in 1843. Four resistances form a diamond with a galvanometer across the middle. When the needle reads zero, the unknown resistance equals a simple ratio of the others.
Why it mattered. It made resistance measurable with great precision, which telegraph engineers badly needed.
Homeopaths founded the American Institute of Homeopathy, three years before the American Medical Association. Homeopathy became popular in the US in the 1800s.
Why it mattered. Homeopathy was once part of mainstream medicine in several countries.
Ludwig proposed that blood pressure pushes fluid out of the glomerulus by plain physical filtration, and that the tubules then change it on its way. Many scientists thought only a 'vital force' could make urine.
Why it mattered. His filtration idea is the basis of how we explain the kidney today.
Vidi sealed a thin, springy metal box with most of the air removed. As air pressure rises and falls the box squeezes and swells a tiny amount, and levers turn that into a needle on a dial. It was small, safe and easy to carry, unlike a long glass tube of mercury.
Why it mattered. It put barometers in homes and ships, and later became the aircraft altimeter.
Boisselot & Fils, then Albert SteinwayParis, France, and New York, USA
A pedal that holds up only the dampers of keys already pressed was first shown by Boisselot & Fils at the Paris exhibition of 1844. Albert Steinway perfected and patented this sostenuto pedal in 1874.
Why it mattered. It lets a pianist hold one chord while playing other notes cleanly.
Joule let falling weights spin a paddle wheel in an insulated can of water and measured how much the water warmed. The same amount of work always gave the same amount of heat: 819 foot-pounds per British thermal unit in 1845, refined to about 772 by 1850.
Why it mattered. It proved that work and heat are both energy, which is why the unit of work is the joule.
Waterston, a Scot teaching naval cadets for the East India Company in Bombay, worked out a detailed theory of gases made of moving molecules. He sent it to the Royal Society in London, and a referee wrote that it was "nothing but nonsense". It sat in the archive until Lord Rayleigh found and printed it in 1892, nine years after Waterston died.
Why it mattered. His ideas were right, and the story is still told as a warning about ignoring outsiders.
Joule, from a brewing family, let falling weights spin a paddle wheel in water and measured how much warmer the water got. Over years of careful work he showed that the same amount of work always makes the same amount of heat. In Germany, Julius Robert Mayer had argued for the same idea in 1842.
Why it mattered. Heat and work turned out to be one thing, energy, which led straight to the first law.
Joule let a falling weight turn a paddle wheel inside a can of water and measured the tiny rise in temperature. After years of careful repeats, in 1849 he reported that 772 foot-pounds of work warm one pound of water by one degree Fahrenheit. That is within about 1 percent of the modern value.
Why it mattered. It turned the link between work and heat into a precise, trusted number.
Julius Weisbach and Henry DarcyFreiberg, Saxony, and Paris
Real water loses pressure along a pipe because it rubs on the walls. Weisbach wrote the friction loss as f × (L/D) × ½ρv² in 1845, and Darcy's careful pipe experiments of the 1850s pinned down how the factor f depends on the pipe.
Why it mattered. It fixed Bernoulli's biggest blind spot for engineers who build water mains.
While still a student, Kirchhoff generalised Ohm's work into two rules: the currents into any junction add up to the currents out, and the voltages round any loop add up to zero.
Why it mattered. With Ohm's law and Kirchhoff's rules you can work out any network of resistors.
William T. G. Morton and John Collins WarrenMassachusetts General Hospital, Boston
In a packed operating theatre, the dentist William Morton had a patient breathe ether vapour until he was unconscious, and the surgeon John Collins Warren removed a tumour from his neck. The patient felt no pain. News of anaesthesia spread around the world within months.
Why it mattered. Before anaesthesia, surgery had to be done in minutes on a screaming patient; after it, careful operations became possible.
Hutchinson built a spirometer, a bell floating in water that rises as you blow into it. He measured thousands of people and named the biggest breath you can blow out the 'vital capacity'. He found it grows with height and falls with age and illness.
Why it mattered. Blowing into a spirometer is still how doctors test lungs today.
Hutchinson built a spirometer, a bell floating in water that rises as you blow into it. He measured thousands of people and named the biggest breath you can blow out the ‘vital capacity’. He found it grows with height and falls with age and illness.
Why it mattered. Blowing into a spirometer is still how doctors test lungs today.
Carhart patented a bellows that pulls air in through the reeds instead of pushing it out through them. Melodeons with suction bellows soon spread through American homes. After 1885 Mason & Hamlin also adopted suction, and it became the American standard, while the French harmonium kept pushing air.
Why it mattered. It split reed organs into two families: pressure harmoniums and suction organs.
Urbain Le Verrier and Johann GalleParis, France, and Berlin, Prussia
Uranus kept drifting from where Newton's law said it should be. Le Verrier calculated that an unseen planet must be pulling it, and where to look. Galle pointed the Berlin telescope there and found Neptune within about 1 degree of the prediction on his first night. John Couch Adams in England had made similar calculations.
Why it mattered. It was a triumph for Newton's gravity: a new world discovered by mathematics.
Armstrong, then a lawyer, persuaded Newcastle to let him drive a quayside crane with the pressure of the new water mains. It worked so well that more followed, and he gave up law to build hydraulic cranes, sold around the world.
Why it mattered. It showed that pressure piped from far away could do heavy work, a network of force.
Mothers were dying of childbed fever far more often in the ward run by doctors, who came straight from dissecting bodies, than in the midwives’ ward. Semmelweis made the doctors wash their hands in chlorinated lime, and deaths fell from about 18% in April to about 1–2% within a few months.
Why it mattered. Hand-washing is still one of the cheapest life-savers in medicine, though Semmelweis was mocked for it in his lifetime.
Babbage designed Difference Engine No. 2 between 1846 and 1849, with a printing unit that would print results onto paper and press them into soft moulds for making printing plates. It was never built in his lifetime. London's Science Museum finished building the engine, and then its printer in 2002.
Why it mattered. It was perhaps the first design for a computer printer: a machine that writes its own answers, with no person copying them out.
Ignaz Semmelweis noticed that far more mothers died of childbed fever on the ward run by doctors, who came straight from dissections, than on the ward run by midwives. He made staff wash their hands in chlorinated lime, and deaths on his ward dropped sharply.
Why it mattered. Handwashing became one of the simplest and most powerful ways to keep mothers and babies safe.
Government of Mysore, under British ruleBangalore, India
The Bangalore Lunatic Asylum opened in 1847. It was renamed the Mental Hospital in 1925 and later grew into one of India’s leading institutes for the brain and mind.
Why it mattered. It is the root of NIMHANS, India’s national institute for mental health and neurosciences.
Theobald Boehm, with Karl von SchafhäutlMunich, Bavaria
After acoustic studies with the scientist Karl von Schafhäutl, Boehm built a new flute of metal with a straight, cylindrical tube and a head joint that narrows in a smooth curve. Its holes were so big that fingertips could not cover them, so he covered them with keys. Almost every concert flute today follows this design.
Why it mattered. The Boehm flute gave the instrument a bigger, even sound and better tuning across all its notes.
Helmholtz was a 26-year-old army surgeon when he read his paper Über die Erhaltung der Kraft to the Physical Society in Berlin. Using mathematics, he showed that the same rule covers falling weights, heat, electricity, magnetism and living muscles. The main physics journal turned it down as too speculative, so he printed it as a booklet.
Why it mattered. It stated the conservation of energy as one general law for all of nature.
Frederick Bakewell improved on Bain with rotating cylinders at each end, a design later called the image telegraph. He showed it at the Great Exhibition in London in 1851.
Why it mattered. Spinning drums scanned more evenly than swinging pendulums, and drums stayed in fax and wirephoto machines for a century.
Bernard, a French physiologist, found that pancreatic juice turns fat into a milky mix and splits it. Without this juice, fat was not digested. His memoir on the pancreas came out in 1856.
Why it mattered. It showed that most of the real work of digestion happens in the small intestine, with juice from the pancreas.
Bernard found sugar in the liver, even in animals that had eaten no sugar, while other tissues had none. Scientists had thought only plants could make sugar and animals just burned it. Bernard showed the liver makes sugar itself and releases it into the blood.
Why it mattered. It proved animal bodies build chemicals, not only break them down.
Bernard, a French physiologist, found in 1848 that pancreatic juice turns fat into a milky mix and splits it into smaller pieces. He showed that without this juice, fat is not digested. His famous memoir on the pancreas came out in 1856.
Why it mattered. It showed that the real work of digestion happens in the small intestine, helped by juice from the pancreas.
Phineas Gage and Dr John HarlowCavendish, Vermont, USA
A tamping iron blasted through the left frontal lobe of railway foreman Phineas Gage. He survived and could walk and talk, but his doctor reported that his personality changed. Historians now think he later recovered much of his social skill.
Why it mattered. His case suggested the frontal lobes shape behaviour and self-control.
In Christmas lectures for young people, Faraday burned candles and caught what came off. He showed that the wax turns into water and carbon dioxide, using oxygen from the air, and that we do the same when we breathe. He gave the lectures again in 1860, and they became a famous book.
Why it mattered. It is still one of the best explanations of combustion ever written for young people.
William Thomson (later Lord Kelvin)Glasgow, Scotland
Thomson, aged 24, used Carnot's ideas to propose a temperature scale that does not depend on any one liquid or gas. It starts at an absolute zero, the coldest anything can ever be, which works out to about minus 273 degrees Celsius. We now measure it in kelvins, named after him.
Why it mattered. Temperature got a true zero, which later made the third law possible.
Berthold removed the testes from young roosters, and they grew up without big red combs or crowing and fighting. When he put a testis back in a different place in the belly, the rooster grew up normal. No nerves had been reconnected, so something must travel in the blood.
Why it mattered. It is widely called the first experiment in endocrinology, showing that a gland can work through the blood.
With very sensitive meters, du Bois-Reymond detected a brief change in a nerve’s electrical charge whenever it carried a signal. We now call it the action potential.
Why it mattered. It showed the nerve signal itself is electrical.
Bourdon patented a gauge built around a curled, flattened metal tube. When the pressure inside rises, the tube tries to straighten, and that small movement swings a pointer. Edward Ashcroft bought the American rights in 1852. The same design still sits on boilers, gas cylinders and tyre pumps.
Why it mattered. It made high pressures easy to read at a glance, which made steam power safer.
His teacher had said nerve signals were too fast ever to measure. Helmholtz stimulated a frog’s nerve at two different distances from the muscle and timed the twitches. The difference gave a speed of about 27 metres a second (his runs gave roughly 25 to 43).
Why it mattered. Thought and feeling became physical processes that take time.
Lala Bhavani Das, then Qadir Bakhsh and Fakir BakhshLahore, Punjab
In Punjab a famous pakhawaj tradition began with Lala Bhavani Das. Later players in Lahore, including Qadir Bakhsh and Fakir Bakhsh, moved its big, bold compositions onto the tabla. This became the Punjab gharana, the school of Alla Rakha and Zakir Hussain.
Why it mattered. It carried the power of the old pakhawaj into the new drum.
Inside the top of a guitar are thin wooden struts called braces. Martin is generally credited with developing X-bracing in the 1850s: two braces crossing in an X below the sound hole. Historians say Martin may not have invented it, but was the first to use it on a large scale.
Why it mattered. X-bracing let a thin top survive the pull of steel strings, and nearly every steel-string guitar uses it today.
Faraday noticed that two pieces of ice pressed together freeze into one, even in warm air. He suggested that ice is covered by a thin film of liquid even below 0 °C. James Thomson and his brother William, later Lord Kelvin, argued instead that pressure melts the ice.
Why it mattered. The argument over why ice is slippery lasted until X-ray studies in the 1980s and 1990s found Faraday's layer.
Houghton won US patent 7,365 for a ‘table furniture cleaning machine’. It was a wooden tub with a rack for dishes and a paddle wheel that you turned by hand to throw hot water over them. It could not really replace scrubbing.
Why it mattered. It was the first time anyone patented the idea of a machine that splashes water onto dishes.
Léon Foucault; Hippolyte Fizeau and Louis BreguetParis
Foucault sent two beams to a fast-spinning mirror, one through air and one through a tube of water. The water beam came back later, so light was slower in water. Fizeau and Breguet found the same seven weeks later. Descartes and Newton had thought light went faster in water.
Why it mattered. It settled the argument: the bend comes from light slowing down, just as Fermat and Huygens said.
Clausius showed that Carnot and Joule were both right. Energy is never lost, only changed, which is the first law. And heat does not flow by itself from something cold to something hot, which is the heart of the second law.
Why it mattered. It is widely seen as the birth of thermodynamics as a science.
Clausius showed how Carnot's ideas about engines could fit with Joule's discovery that heat and work are the same kind of thing. He wrote that the heat you add to a gas either raises its internal energy or does work. Today this is called the first law of thermodynamics.
Why it mattered. Energy conservation became the first law of the new science of heat.
Charles Xavier Thomas de Colmar patented his arithmometer in 1820, and from 1851 it was made and sold in numbers. Based on Leibniz's stepped drums, it was the first mechanical calculator strong and reliable enough for offices, insurers and banks, and was made until about 1915.
Why it mattered. Calculating machines stopped being curiosities and became office equipment.
Mathijsen, a Dutch army surgeon, rubbed plaster of Paris into cloth bandages. Wetted and wrapped around a broken limb, they set hard in minutes, instead of the day that older starch bandages took. He tried it on chickens first, and his method spread around the world within about ten years.
Why it mattered. The plaster cast made it easy to hold a broken bone still while it heals.
The Italian anatomist Alfonso Corti used a microscope to describe the strip of hair cells and supporting cells on the basilar membrane. His paper appeared in 1851, and the structure is still called the organ of Corti.
Why it mattered. It is where sound actually becomes a nerve signal.
Helmholtz built the ophthalmoscope, a mirror that sends light into the eye and lets a doctor look along the same path to see the retina, its blood vessels and the optic disc.
Why it mattered. For the first time doctors could see diseases of the retina and optic nerve in living patients.
Foucault hung a heavy bob on a 67 m wire in the Panthéon. As it swung, its line slowly turned round through the day, because the floor, the Earth, was turning underneath it.
Why it mattered. It showed the Earth is a rotating frame, where Coriolis effects are real but slow.
Exhibitors at the Great ExhibitionCrystal Palace, London, England
A gas stove was shown to the crowds at the Great Exhibition. Even so, most people still cooked on coal, and gas cookers only became a commercial success in England in the 1880s.
Why it mattered. New kitchen ideas can take decades to reach ordinary homes, as LPG in India would too.
Gorrie cooled the rooms of patients sick with fevers like yellow fever by blowing air over ice. Shipped ice was scarce, so he built a machine that compressed air to make ice, and won US patent 8,080. It failed as a business, but his model is kept at the Smithsonian.
Why it mattered. It was one of the first attempts to cool rooms, not just food, with a machine.
William Thomson (later Lord Kelvin)Royal Society of Edinburgh, Scotland
Thomson gave his own version of the second law. No engine working in a cycle can take heat from one place and turn all of it into work. Some heat must always be passed to something colder.
Why it mattered. It explains why every car engine and power station has to throw heat away.
The wet collodion process coated glass plates just before exposure. It combined the sharpness of the daguerreotype with printable negatives, and exposures fell to a few seconds.
Why it mattered. It made photography practical for portraits, war reporting and travel. Archer didn't patent it.
Georg Meissner and Rudolf WagnerGöttingen, Germany
Working in Rudolf Wagner's lab, the young Georg Meissner found small oval bodies wrapped around nerve endings in the ridges of fingertip skin. The two published them together in 1852, then argued for years over who deserved the credit. Meissner corpuscles sense light touch and gentle flutter.
Why it mattered. It linked a feeling, light touch, to a structure you can see in the skin.
Foucault spun a heavy rotor in gimbals and watched its axis hold still while Earth turned beneath it, for the eight to ten minutes it kept spinning. He named it the gyroscope, from Greek words for 'turn' and 'watch'.
Why it mattered. Spin and torque became a tool to see Earth's own rotation.
Antonio de Torres made his guitars bigger, but with thinner, lighter tops held up by a fan of braces. In 1862 he even built one with papier-mâché back and sides, to show that the top, not the back, makes the sound. He used a string length of about 650 mm, which classical makers still follow.
Why it mattered. Most classical guitars today are still built to Torres’s plan.
Foucault spun a heavy wheel in a set of rings and watched its axis hold its direction in space while the Earth turned underneath. He called it a gyroscope, 'to see the rotation'.
Why it mattered. Rotational inertia became a tool, now used in compasses, ships and spacecraft.
The Metropolis Water Act said that all of London's drinking water had to be effectually filtered from the end of 1855. Later laws added regular checks of what was in the water.
Why it mattered. It was one of the first laws anywhere to demand treated drinking water.
William Rankine, William Thomson (Lord Kelvin) and Peter Guthrie TaitGlasgow and Edinburgh
In 1853 the Scottish engineer Rankine wrote about 'the law of the conservation of energy' and coined 'potential energy' for stored energy, like a raised weight. He called the energy of motion 'actual energy'. Thomson and Tait swapped that for 'kinetic energy', which appeared in their 1862 article titled Energy.
Why it mattered. These are the two words every student now uses to describe energy stored and energy in motion.
During a cholera outbreak, the doctor John Snow marked each death on a street map and found them clustered around one water pump on Broad Street. He persuaded the local council to take off the pump handle, and showed that cholera spreads through dirty water, not bad air.
Why it mattered. It founded epidemiology: finding the cause of disease by counting who gets ill and where.
George Boole, a self-taught English mathematician working in Ireland, published The Laws of Thought. He showed that true and false could be handled like numbers, with rules for AND, OR and NOT.
Why it mattered. Boole's algebra of true and false is exactly what a computer's logic gates do.
Snow mapped cholera deaths in Soho and traced them to one water pump, whose well was polluted by a nearby cesspit. When the handle was removed the outbreak was already fading, but his evidence stuck.
Why it mattered. It showed that human waste in drinking water spreads deadly disease.
Mustel, a carpenter from Le Havre, patented his double expression in 1854. Knee levers let the player make the bass and the treble louder or softer on their own. His harmonium won a first-class medal at the Paris Exposition of 1855, and Mustel harmoniums became among the most admired in Europe.
Why it mattered. It let players shape the sound almost like a singer.
When cholera killed hundreds of people in Soho, the doctor John Snow marked each death on a map. The deaths clustered around one water pump on Broad Street. He persuaded the local officials to take the pump's handle off.
Why it mattered. It helped prove that dirty water spreads disease, the reason we purify drinking water at all.
A Swiss dye-works owner turned healer opened a centre where patients sunbathed, walked in light clothes and slept in open-air huts, his 'atmospheric cure'.
Why it mattered. It added sun and air to water, two of naturopathy's five elements.
Thomas Addison published a short book about patients who grew weak, thin and oddly bronze-skinned before they died. When the bodies were examined, their adrenal glands were damaged. The illness is now called Addison's disease.
Why it mattered. It was the first clear link between a damaged gland and a disease of the whole body.
Cooks in Chile, Belgium and France (disputed)Chile, Belgium and Paris, France
A Chilean manuscript mentions papas fritas, fried potatoes, eaten in 1629. A famous Belgian story says villagers fried potato slices before 1680, but historians doubt it. The long thin fries we know most likely took shape in Paris around 1855.
Why it mattered. Fries became the food that air fryers are judged on.
The young German physiologist Adolf Fick, working in Zurich, argued that salt spreads through water just as heat spreads through a metal bar. The flow of stuff is proportional to how steeply its concentration changes. He tested it with salt diffusing up tall columns of water.
Why it mattered. Fick's law is still how we calculate diffusion everywhere, from oxygen crossing the lungs to dye spreading in a glass.
Robert Bunsen and Peter DesagaUniversity of Heidelberg, Germany
The chemist Robert Bunsen wanted a hot, clean flame for his new laboratory. The university mechanic Peter Desaga built the burner, which mixes gas with air before it burns, and made 50 of them by the time the lab opened in 1855. Michael Faraday had used a similar idea earlier.
Why it mattered. Mixing air in first gives a hot blue flame with no soot. Every gas hob burner uses this trick.
Soon after Addison's book, Brown-Séquard removed the adrenal glands from animals. They all died quickly. So these small glands were not spare parts: life depended on them.
Why it mattered. It proved by experiment what Addison had seen in his patients.
The French physiologist Claude Bernard showed that pancreatic juice breaks down fats, and also starch and protein, far better than stomach juice. Soon after, he found that the liver stores sugar as glycogen and releases it into the blood.
Why it mattered. He proved the pancreas is the gut's main enzyme factory, and that the body controls its blood sugar.
Collier, a tinsmith, patented a mixer with rotating parts. Within a few years inventors were selling hand-cranked rotary egg beaters, where gears turn a slow crank into fast-spinning beaters.
Why it mattered. Gears showed that a slow hand could make a whisk spin fast, the same trade of force for speed a motor makes.
Harrison, a Scottish-born printer and newspaper owner, reportedly noticed that ether used to clean metal type made the metal cold. He built machines that compressed ether vapour and turned it back into a liquid, first to make ice and then to cool a brewery in Bendigo. He patented his process in Britain in 1856 and his apparatus in 1857.
Why it mattered. He is widely credited with the first practical vapour-compression machine, doing real work in industry.
Foote put thermometers inside glass cylinders filled with different gases and set them in sunlight. The cylinder with carbonic acid gas, which we call carbon dioxide, heated up the most and took longest to cool. Her paper was read at a science meeting in Albany by Joseph Henry of the Smithsonian, and she suggested that more of this gas in the air would make the Earth warmer.
Why it mattered. She was the first known person to link carbon dioxide with a warmer planet.
Bernard found that the liver makes sugar even in animals fed no sugar, and in 1857 he isolated the starch-like store it comes from, glycogen. Blood from the gut reaches the liver first, which stores and releases what the meal provided.
Why it mattered. It showed that absorbed food is managed by the liver, not simply burned.
Bernard washed a liver clean of sugar, yet found new sugar in it the next day. Something in the liver was turning into sugar. In 1857 he isolated that substance and described it as animal starch. We call it glycogen.
Why it mattered. It explained how the liver stores energy after a meal and releases it between meals.
Rudolf Clausius (and August Krönig in 1856)Zürich, Switzerland
A year after August Krönig in Berlin, Clausius published a fuller theory of gases as molecules racing about and bumping into things. He showed how their speed sets the pressure and the temperature, and later worked out how far a molecule travels between bumps. Together they turned Bernoulli's old picture into real physics.
Why it mattered. It explained where PV = nRT comes from: it is just molecules hitting walls.
Rudolf Virchow, then Louis Pasteur and Robert KochBerlin and Paris
Virchow’s Cellular Pathology (1858) explained disease as trouble in cells, and in the following decades germ theory showed that microbes cause many illnesses. European medicine left the four humours behind.
Why it mattered. It is the split between modern medicine and humoral systems like Unani.
After the smelly summer of 1858, Parliament paid for a network of brick sewers that carried waste far downstream. Its main parts were finished by 1875 and are still in use.
Why it mattered. Cities learned that sanitation is infrastructure, like roads.
After Richard Carrington saw a brilliant flare on the Sun, the biggest magnetic storm on record hit the Earth. Colaba's hand-read instruments saw the horizontal field drop by about 1,600 nanotesla, far more than in any storm since, and aurora were seen close to the tropics.
Why it mattered. Colaba's readings are among the best measurements of how strong a solar storm can be.
Carré built a machine that used heat, not a pump, to push ammonia around a loop: water soaks up ammonia gas, and heating the water drives the gas out again under pressure. It was patented in France in 1859 and in the US in 1860. During the American Civil War one of his machines was smuggled through the Union blockade to make ice in Texas.
Why it mattered. It showed that heat alone can power a fridge, an idea still used where there is no steady electricity.
Tyndall sent infrared heat through long tubes of different gases and measured how much got through with a sensitive heat detector. Oxygen and nitrogen let almost all of it pass. Water vapour and carbon dioxide soaked it up, with water vapour the strongest absorber in air.
Why it mattered. His careful measurements showed exactly how gases in the air can trap radiated heat.
Kirchhoff showed that, at the same temperature, a surface that absorbs a kind of light well also gives it out well. He imagined a perfect absorber that soaks up every ray that hits it, and called it a black body. He said its glow should depend only on its temperature, but nobody yet knew the formula.
Why it mattered. The hunt for the black body formula led straight to quantum physics.
Planté rolled two sheets of lead into a spiral, kept apart by strips of rubber, and dipped them in dilute sulfuric acid. When the battery ran down, he could push current back in to charge it again. It was the first rechargeable battery.
Why it mattered. The lead-acid battery is still the heavy box sitting next to most home inverters in India.
Steinway & Sons was founded in a Manhattan loft on 5 March 1853. In 1859 Henry Steinway Jr. patented a grand piano with its bass strings crossing over the others at an angle, on an iron frame. That brought the bridges nearer the middle of the soundboard.
Why it mattered. Longer bass strings over the liveliest part of the soundboard gave a richer sound, and nearly every grand is built this way now.
Italian priest and physicist Giovanni Caselli tested his pantelegraph on a telegraph line from Paris to Amiens, about 140 km. The image sent was the signature of the composer Gioacchino Rossini.
Why it mattered. It proved a picture or handwriting could survive a real long-distance line.
Missionaries, traders and the Tagore familyKolkata (Calcutta), India
Portable reed organs came to India in the mid-1800s, carried by missionaries, chaplains and traders to accompany hymns. In 1860 Dwijendranath Tagore used an imported one in his private theatre in Calcutta. Nobody knows exactly where in India the first one arrived.
Why it mattered. It planted a European church instrument in a land with a very different music.
Louis Dorus and flute maker Louis LotParis Conservatoire, France
When Louis Dorus became professor of flute at the Paris Conservatoire in 1860, he persuaded the school to make the Boehm flute the official flute for its students. The maker Louis Lot became official supplier of flutes to the Conservatoire. Players trained there spread the new flute and a light, bright French style around the world.
Why it mattered. With Paris behind it, the Boehm flute beat its rivals and became the standard.
Joseph Malin, and John Lees (attributed)Bow, London, and Mossley, Lancashire, England
Joseph Malin is said to have opened the first shop selling fried fish with chips in east London around 1860. John Lees did something similar in the north of England around 1863. Fried fish is often said to have come to Britain with Jewish families of Spanish and Portuguese origin, though historians still argue about the details.
Why it mattered. Deep-fried food became cheap everyday food, and later a health worry.
Lenoir, born in what is now Belgium, patented an engine in 1860 that burned coal gas and air, lit by electric sparks. Hundreds were sold to power workshops. In 1863 he fitted one to a three-wheeled carriage, the Hippomobile, and drove it about 11 km from Paris to Joinville-le-Pont.
Why it mattered. It was the first internal combustion engine to sell in large numbers, and its spark ignition lives on in every petrol engine.
James Clerk Maxwell, then Ludwig BoltzmannAberdeen, Scotland
Maxwell realised the molecules in a gas have a spread of speeds, a few slow, most in the middle, a few very fast. He worked out the shape of that spread, and it was the first law of physics based on chance. In 1872 Boltzmann in Graz showed why any gas settles into exactly this spread.
Why it mattered. It showed that a gas law is really the average behaviour of trillions of molecules.
Pasteur boiled broth in flasks with long swan-shaped necks. Air could get in but dust and microbes were trapped in the bend, and the broth stayed clear. When he broke the neck, it went cloudy with microbes. Germs come from other germs.
Why it mattered. It led to the germ theory of disease, pasteurisation and, later, Pasteur’s own vaccines.
The German teacher Philipp Reis showed a device he called the Telephon. It sent musical tones, and by some accounts a few words, down a wire. Historians still argue about how well it carried speech.
Why it mattered. It gave the telephone its name, 15 years before Bell's patent.
Broca examined the brain of a patient, Louis Leborgne, who could understand speech but say only one syllable, “tan”. He found damage in the left frontal lobe, the area now called Broca’s area.
Why it mattered. It was strong evidence that particular brain areas have particular jobs.
Mason & Hamlin, Estey and many other firmsBoston, Massachusetts, and Brattleboro, Vermont, USA
Mason & Hamlin, founded in Boston in 1854, launched its American organ in 1861 and showed it in Paris in 1867. Between the 1850s and 1920s, several million reed organs and melodeons were made in the United States and Canada. Estey alone made about half a million.
Why it mattered. The reed organ became the ordinary family's keyboard, long before pianos were cheap.
Graham noticed that small molecules like salt and sugar pass through parchment paper quickly, while gluey substances like gum and gelatin hardly pass at all. He called these colloids and named the separation method dialysis.
Why it mattered. Dialysis became a standard lab tool, and eighty years later the basis of the artificial kidney.
Latimer Clark and Charles Bright; British AssociationManchester and London, England
Clark and Bright proposed naming electrical units after scientists, including the 'ohma'. The British Association set up a committee with Maxwell and William Thomson, and in 1864 it defined the 'B.A. unit' of resistance, later found to be about 1.3% too small.
Why it mattered. Electricity got a shared language, and Ohm's name became a unit.
Duchenne stimulated single muscles through the skin with small electric currents to see what each one does. In 1862 he published photographs of faces made to smile and frown this way. He also invented a needle for taking tiny samples of living muscle.
Why it mattered. He mapped what individual muscles do and started modern muscle medicine.
Georg Meissner and Leopold AuerbachBasel, Switzerland, and Breslau (now Wrocław, Poland)
Meissner described a net of nerve cells under the gut lining, and Auerbach a second net between the gut’s muscle layers. Together they form the enteric nervous system, which runs the gut’s movements.
Why it mattered. It was the first sign that the gut has its own nervous system.
In his book Zur Anatomie der Niere, Henle described the hairpin loop that the tubule makes deep into the medulla, with drawings of its thin and thick parts. For almost a century nobody knew what it was for.
Why it mattered. It is the part of the nephron that lets us make concentrated urine.
Snellen designed letters on a grid, each part one-fifth of the letter's height, so that sharpness of sight could be measured and compared. His chart, with the big E at the top, is still used around the world.
Why it mattered. It turned "I can't see well" into a number, like 6/6 or 20/20.
In On the Sensations of Tone, Helmholtz proposed that the cochlea holds a row of tuned resonators, like piano strings, each answering one pitch. He thought the fibres across the basilar membrane were the strings.
Why it mattered. His idea of a place for each pitch was right in spirit, and set the question Békésy answered.
Hermann von Helmholtz; Robert BosanquetHeidelberg, Germany, and London, England
In his 1863 book On the Sensations of Tone, Helmholtz used a harmonium with 24 notes to the octave, tuned so its chords were perfectly pure. In 1872 to 1873 Bosanquet had a harmonium built with 53 notes to the octave. Steady reeds made harmoniums perfect for hearing tiny differences in tuning.
Why it mattered. It showed that the usual 12 equal notes are a compromise, the same worry later raised in India.
In 1863 Richards and Alexander patented a tub with dishes held in a rack around the edge and curved paddles spinning in the middle. In 1865 Alexander patented a version with gears that spun the dishes through the water. Dozens more dishwasher patents followed over the next 25 years.
Why it mattered. Inventors kept trying, but a hand crank could not move enough water to get dishes truly clean.
Donders' book On the Anomalies of Accommodation and Refraction of the Eye explained myopia, hyperopia, astigmatism and presbyopia and how to measure and correct them with lenses.
Why it mattered. It made fitting glasses a science.
Antonin Prandtl proposed spinning milk so the denser skim milk flies outwards and the lighter cream gathers in the middle. His brother Alexander showed a working machine in 1875.
Why it mattered. It was the start of the centrifuge as an everyday machine.
Pierre Michaux, Pierre Lallement and othersParis, France
French makers fitted cranks and pedals straight onto the front wheel. The Michaux company began producing these velocipedes in quantity in the late 1860s. On cobbled streets their iron tyres earned them the nickname “boneshakers”.
Why it mattered. For the first time, a rider could keep their feet off the ground.
Loschmidt made the first estimate of the size of molecules and how many there are in a given amount of gas. This led to Avogadro's number, 6.022 × 10²³.
Why it mattered. It made it possible to show that high dilutions like 30C hold no molecule of the starting substance, something Hahnemann could not have known.
Giovanni Caselli and the French telegraph serviceParis and Lyon, France
The French telegraph service opened a pantelegraph service between Paris and Lyon, extended to Marseille in 1867. Pendulums kept the machines in step, and the receiving paper was soaked in potassium ferricyanide, which darkened where current passed. It mostly carried signatures and handwritten messages.
Why it mattered. Fax was offered to the public, and paid for, more than a decade before the telephone was invented.
Maxwell gathered everything known about electricity and magnetism into one set of equations. They predicted waves of electric and magnetic field travelling at the speed of light, and he concluded that light is one of them.
Why it mattered. It unified electricity, magnetism and light, and led to radio, microwaves and MRI.
In A Dynamical Theory of the Electromagnetic Field, Maxwell showed that electric and magnetic fields can travel together as a wave. The speed his equations predicted matched the measured speed of light.
Why it mattered. It joined light, electricity and magnetism, and predicted invisible waves nobody had yet made.
Maxwell, a Scottish physicist, wrote down a set of equations that tie electricity and magnetism together. They showed that the two could travel through space as a wave, and that light itself is one of these waves. His equations also said there should be waves much longer than light, which no one had seen yet.
Why it mattered. Microwaves are one of the invisible waves Maxwell's equations predicted.
Maxwell turned Faraday's pictures of 'lines of force' into mathematics. His great paper, read to the Royal Society on 8 December 1864 and published in 1865, predicted waves of electricity and magnetism that travel at the speed of light.
Why it mattered. Faraday's law became one of Maxwell's equations, and light turned out to be electricity and magnetism inducing each other.
Clausius needed a name for the quantity that always grows when heat spreads out. He built the word entropy from the Greek for transformation, and chose it to sound like energy. He summed up: the energy of the universe stays the same, and its entropy tends to a maximum.
Why it mattered. Entropy gave the second law a number you can calculate.
The first rotary ceiling fans in the United States had no electric motor. A stream of water turned a turbine, which drove long belts that spun several two-bladed fans at once in stores, restaurants and offices. In 1886 John Hunter and his son James, immigrants from Ireland, started making water-powered belt fans in Syracuse, New York.
Why it mattered. Ceiling fans were ready and waiting; they only needed a better engine.
Mahendralal Sircar, one of the first MD graduates of Calcutta University, publicly declared his support for homeopathy after being introduced to it by Rajendralal Dutta. He later founded the Indian Association for the Cultivation of Science (1876).
Why it mattered. His support gave homeopathy standing among educated Bengalis.
Christian Lovén and Gustav SchwalbeStockholm, Sweden, and Germany
Working separately, the Swedish anatomist Christian Lovén and the German anatomist Gustav Schwalbe looked at the tongue under the microscope and found small onion-shaped clusters of cells, which they called taste bulbs or taste goblets.
Why it mattered. It showed that taste is sensed by special groups of cells, not by the whole tongue surface.
Moritz TraubeBreslau, Prussia (now Wrocław, Poland)
Moritz Traube found that when copper sulphate meets potassium ferrocyanide they form a thin film of copper ferrocyanide that lets water through but holds back many dissolved substances. It was a membrane made in a test tube instead of taken from an animal.
Why it mattered. Traube's membranes were far more selective than bladders, which made real measurements of osmotic pressure possible.
Samuel Varley, Werner Siemens, Charles WheatstoneLondon and Berlin
Early generators used weak permanent magnets. Varley, Siemens and Wheatstone each found, within weeks of each other, that a dynamo can feed part of its own current into electromagnets and make its field stronger and stronger. Ányos Jedlik in Hungary had the same idea around 1856.
Why it mattered. Big, cheap generators became possible, and the age of electric power began.
In a letter to his friend Peter Guthrie Tait, Maxwell imagined a tiny being guarding a door between two boxes of gas. It lets fast molecules through one way and slow ones the other, so one side gets hot and the other cold without any work. Maxwell made it public in his book Theory of Heat in the early 1870s, and Kelvin later nicknamed it a demon.
Why it mattered. It showed that the second law is about probability, and the puzzle took about a century to solve.
Linnett patented the “kineograph”, a little book of pictures that seem to move when you flick the pages with your thumb. It is the earliest known flip-book patent.
Why it mattered. Every animator’s first tool is still a pile of paper flipped under the thumb.
Duchenne described boys whose calf muscles looked big but grew steadily weaker, and examined their muscle under the microscope. The condition now carries his name: Duchenne muscular dystrophy.
Why it mattered. It began the scientific study of muscular dystrophies.
Breuer, a young doctor working in Hering's lab, found that stretching an animal's lungs made it stop breathing in for a while. The message travelled to the brain along the vagus nerve. This is now called the Hering-Breuer reflex.
Why it mattered. It showed that breathing is a loop: sensors in the lungs report back, and the brain adjusts each breath.
Paul Langerhans, a 21-year-old medical student, spotted branching cells in the epidermis. Because of their branches he thought they were part of the nervous system. They turned out to be immune cells that catch germs and show them to the body's defences.
Why it mattered. The skin is not just a wall: it has its own guards.
Kussmaul pushed a straight, rigid metal tube, lit from outside by a lamp, down the throat of a professional sword swallower and looked into his stomach. It worked, but the light was poor and the tube dangerous for ordinary patients.
Why it mattered. It was the first look inside a living human stomach through the mouth.
Maughan, a painter, invented a water heater for the home that burned gas instead of wood or coal. Cold water ran through pipes heated by the gas flame and came out hot, straight into the bath. It had no flue to carry the fumes away, so it could be dangerous.
Why it mattered. It was the first instant water heater for homes, and its name ‘geyser’ is still what much of South Asia calls a water heater.
Pierre Michaux and Louis-Guillaume PerreauxParis, France
Perreaux fitted a small steam engine to one of Michaux's iron-framed velocipedes. Its boiler sat under the saddle and belts drove the back wheel. In the United States, Sylvester Roper built steam cycles around the same time.
Why it mattered. Before petrol engines were light enough, people were already trying to make bicycles move by themselves.
A 1,200 m race in the park of Saint-Cloud is often cited as the first recorded bicycle race. It was won by James Moore, an English rider living in France.
Why it mattered. Racing drove bicycle design from the start.
The Government Oriental Manuscripts Library opened in Madras, starting with Colin Mackenzie's collection. Today it holds about 50,000 palm-leaf and 22,000 paper manuscripts, including Siddha medical texts.
Why it mattered. Much of Siddha's written heritage survived because libraries like this collected and copied it.
As a 22-year-old medical student, Paul Langerhans looked at the pancreas under a microscope. He saw small clusters of cells scattered like islands among the cells that make digestive juice. He did not know what they did.
Why it mattered. These islets of Langerhans turned out to make insulin.
Jaques-Louis Reverdin, a Swiss surgeon training in Paris, placed tiny pinches of healthy skin onto a wound that would not heal. Each little island spread outwards until the wound closed over. These pinch grafts began the modern era of skin grafting.
Why it mattered. It proved that skin cells can spread and cover a wound, the idea behind every skin graft.
In his thesis, 22-year-old medical student Paul Langerhans described small clusters of cells, scattered through the pancreas, that looked different from the rest. He honestly wrote that he did not know what they were for.
Why it mattered. These islets turned out to make insulin, and they still carry his name.
Andrews squeezed carbon dioxide at different temperatures. Below about 31 °C, squeezing turned it into a liquid. Above that temperature, no amount of squeezing made a liquid at all. He called this the critical point and described it in the Royal Society's Bakerian Lecture.
Why it mattered. It showed real gases break the ideal gas law, and explained how to turn gases into liquids by cooling them first.
Meyer built wheels whose thin wire spokes were pulled tight, instead of heavy wooden spokes that push. The rim is held in shape by tension from every side.
Why it mattered. Light, strong wheels made bigger, faster bicycles possible, and every spoked wheel since works this way.
The Italian inventor Antonio Meucci had been working on a talking telegraph, his telettrofono, for years. Too poor to pay for a full patent, he filed a cheaper caveat in 1871 and let it lapse in 1874. In 2002 the US House of Representatives passed a resolution saying his work in the invention of the telephone should be acknowledged. Who deserves the most credit is still debated.
Why it mattered. The telephone had several parents, and not all of them got the credit.
James Starley and William Hillman (Ariel)Coventry, England
With the pedals fixed to the front wheel, the only way to go further per pedal turn was a bigger wheel. Front wheels grew to 1.5 m across. Later nicknamed “penny-farthings”, they were fast but dangerous: a bump could pitch the rider headfirst over the bars.
Why it mattered. A giant wheel was a gear ratio you could see. Chains would soon do the same job safely.
Ranvier noticed that red muscles in rabbits contracted slowly and steadily, while pale muscles twitched fast. It was the first clear sign of slow and fast muscle fibres.
Why it mattered. Sprinters and marathoners differ in exactly this mix.
Kölliker, a Swiss anatomist, wrote a book on how bone is normally dissolved. He described large cells with many nuclei sitting in little pits on the bone surface, and named them osteoclasts, bone breakers. We now know they work with bone-building cells called osteoblasts.
Why it mattered. It explained who does the removing when bone remodels.
Working in a hospital kitchen turned laboratory, Golgi found that silver staining turns a few whole nerve cells jet black, branches and all, against a clear background.
Why it mattered. For the first time single neurons could be seen complete.
Golgi found that silver nitrate stains a few nerve cells completely black, showing every branch. For the first time, single neurons could be seen whole under a microscope.
Why it mattered. His stain made it possible to study the brain one cell at a time.
Maxwell's theory of electromagnetism predicted that light carries momentum and presses on anything it hits. The pressure of sunlight on Earth, he worked out, is tiny: a few millionths of a pascal.
Why it mattered. It meant momentum was not just for things with mass.
British Association for the Advancement of ScienceUnited Kingdom
A committee of British scientists set up the centimetre-gram-second system and named its unit of force the dyne, from the Greek word for power. One dyne speeds up one gram by one centimetre per second, every second.
Why it mattered. It was an early unit of force built from Newton's law instead of from the weight of a lump of metal.
Van der Waals, a former schoolteacher, fixed the ideal gas law in his PhD thesis. He added two corrections: molecules take up some space, and they pull on each other a little. His equation described gases and liquids together, and Maxwell praised it in the journal Nature.
Why it mattered. It won him the 1910 Nobel Prize in Physics and is still the first step past PV = nRT.
Carl WernickeBreslau, then Germany (now Wrocław, Poland)
Wernicke described patients who spoke fluently but made little sense and struggled to understand others. The damage was in the left temporal lobe, in what is now called Wernicke’s area.
Why it mattered. It showed that language relies on connected areas, not a single spot.
S. M. Tagore, a music scholar who ran a music school, published Harmonium Sutra, a guide to playing the harmonium with an Indian notation. Early music schools across North India taught the harmonium to large numbers of students.
Why it mattered. Students wanted harmoniums, which gave makers a reason to build one for Indian music.
Dmitri Mendeleev (and August Horstmann in 1873)St Petersburg, Russia
Earlier versions of the gas law used a different constant for each gas. Mendeleev, famous for the periodic table, used Avogadro's idea to write the law for a mole of any gas as pV = RT, with one shared R. His value was within about 0.3% of today's. In Russia the ideal gas law is still called the Clapeyron–Mendeleev equation.
Why it mattered. The single R is what makes PV = nRT work for every gas.
Friedrich Merkel gave the first full description of special cells at the base of the epidermis, each paired with a nerve ending. He called them Tastzellen, touch cells. Today Merkel cells are known to help us feel edges, shapes and textures.
Why it mattered. It added another type of sensor to the growing map of how skin feels.
Dwarkanath Ghose (Dwarkin & Son)Lower Chitpur Road, Kolkata (Calcutta), India
Dwarkanath Ghose started a music business in Calcutta in 1875, the firm later called Dwarkin. He is widely credited with the Indian harmonium: a small box you pump by hand from the back, played sitting on the floor with singers and drummers. He made it simpler and tougher, and added drone stops for Indian music.
Why it mattered. This is the design almost every Indian harmonium still follows.
After a cyclone struck Calcutta in 1864 and monsoon failures caused famines in 1866 and 1873, the government set up one weather service for the whole country. Barometer readings from stations across India could now be collected and compared. Falling pressure in one place helps forecasters spot storms and follow the monsoon.
Why it mattered. Pressure readings became a tool for warning millions of people about cyclones.
Crookes and other scientists pumped most of the air out of glass tubes and ran a high voltage through them. Invisible 'cathode rays' streamed from one end and made the glass glow green. These rays were later shown to be electrons.
Why it mattered. Every early X-ray machine was a tube like this: fast electrons hitting something hard is what makes X-rays.
Bell's lawyer filed his patent application on 14 February 1876, the same day Elisha Gray filed a caveat for a similar idea. US patent 174,465 was granted on 7 March. Three days later Bell spoke the first words over his liquid transmitter: 'Mr. Watson, come here, I want to see you.'
Why it mattered. It was one of the most valuable patents ever, and the start of the Bell telephone companies.
Oscar HertwigMediterranean coast (sea urchin eggs); based at Jena, Germany
Oscar Hertwig studied the clear eggs of a Mediterranean sea urchin, which are easy to see through. He mixed eggs and sperm and watched a single sperm enter an egg. About ten minutes later the sperm's nucleus had travelled to meet the egg's nucleus and joined with it.
Why it mattered. It showed that fertilisation is the joining of one sperm and one egg, nucleus with nucleus.
Karl Wilhelm von KupfferKönigsberg, Prussia (now Kaliningrad, Russia)
Using a gold stain, Kupffer saw star-shaped cells, which he called Sternzellen, along the liver's tiny blood channels. At first he thought they were a kind of connective tissue cell. Some historians think he was actually seeing a different cell type that stores vitamin A.
Why it mattered. It started the hunt for the liver's own cleaning cells.
Bell taught deaf pupils in Boston, using his father's "visible speech" system, and opened his own school in 1872. His study of speech and sound led to the telephone, patented on 7 March 1876. Many Deaf people today criticise his push to teach speech in place of sign language.
Why it mattered. The unit of sound level, the bel and the decibel, is named after him.
Boll saw that the reddish-purple colour of a frog's retina faded in bright light and came back in the dark. The pigment, rhodopsin, was then studied by Wilhelm Kühne.
Why it mattered. It was the first clue to how light is caught by the eye's chemistry.
Samuel Plimsoll, a member of parliament, campaigned against overloaded 'coffin ships' that sank with their crews. The Merchant Shipping Act of 1876 made a load line mark compulsory: a circle with a line through it on each ship's side. Its exact position was fixed by law in 1894.
Why it mattered. Buoyancy became a safety rule painted on every ship in the world.
Linde, an engineering professor, built his first refrigeration machine for the Spaten brewery in Munich in 1873. By 1876 he had a reliable, efficient machine that compressed ammonia, and in 1879 he founded a company to sell his ice machines.
Why it mattered. Brewers, meat packers and ice plants could now make cold dependably, on demand.
Otto built an engine that sucked in fuel and air, squeezed it, burned it and pushed out the exhaust, in four strokes of the piston. Squeezing the mixture before lighting it made it far more efficient than earlier gas engines.
Why it mattered. Nearly every petrol car and motorbike engine still works this way.
Margaret P. ColvinBattle Creek, Michigan, and Philadelphia, USA
Margaret Colvin, a mother of seven, patented an improved washing machine in 1871: a hollow cylinder that turned inside a boiler and could clean many kinds of cloth without damaging them. She showed her Triumph Rotary Washer in the Women's Pavilion at the Centennial Exhibition in Philadelphia in 1876. It did so well that her husband left farming to make and sell it.
Why it mattered. The people who did the washing were often the ones who best understood how to make it easier.
Otto's company Deutz ran a new engine in 1876 that worked in four strokes: draw in fuel and air, squeeze it, burn it, push out the exhaust. Squeezing the mixture first made it far stronger and smoother than older gas engines. German patent DRP 532 followed on 4 August 1877, though a Frenchman, Alphonse Beau de Rochas, had described the idea in 1862.
Why it mattered. Almost every petrol car engine still runs on Otto's four-stroke cycle.
Gibbs, a quiet professor at Yale, published a very long paper called On the Equilibrium of Heterogeneous Substances in a small local journal. It used energy and entropy to predict when chemicals react, when ice melts and when mixtures separate. It took Europe years to notice.
Why it mattered. It turned thermodynamics into a tool for chemistry and materials science.
Thomas Edison, David Edward HughesMenlo Park, USA; London, England
Early telephones were faint. Thomas Edison filed a patent in 1877 for a transmitter that used carbon, whose resistance changes when pressed. David Edward Hughes showed a carbon 'microphone' in London in 1878, and many historians credit him with the idea. Carbon microphones were used in telephones for about a hundred years.
Why it mattered. The carbon microphone let a voice control a battery's current, making calls loud enough to be practical.
Maximilian Nitze and Josef LeiterDresden, Germany, then Vienna, Austria
Nitze showed his first cystoscope in Dresden in 1877, lit by a glowing platinum wire cooled with water. With the Viennese instrument maker Leiter he made a practical version, first shown on a patient in 1879.
Why it mattered. Doctors could finally look inside the bladder instead of guessing.
In his book The Theory of Sound, Lord Rayleigh worked out the physics of air vibrating in pipes. He showed that the vibrating air pokes out a little past an open end, so the pipe acts as if it were longer, by roughly 0.6 times its radius. Flute makers still allow for this end correction when they place holes.
Why it mattered. It explains why the note of a flute depends on the length of air that rings, not just the length of the tube.
The botanist Wilhelm Pfeffer grew a Traube membrane inside the pores of an unglazed clay pot, so it could stand high pressure. Filled with sugar solution and sealed to a pressure gauge, it gave the first reliable numbers: the pressure grew with the concentration and with the temperature. He published them in his book Osmotic Investigations.
Why it mattered. These were the numbers van 't Hoff would turn into a law. A weak 1% sugar solution already pushed with about two-thirds of an atmosphere.
The botanist Wilhelm Pfeffer made a man-made membrane inside the wall of an unglazed clay pot. With sugar water inside and pure water outside, water flowed in and pushed up the pressure. He measured that pressure and found it grew with how much sugar there was.
Why it mattered. It was the first measurement of osmotic pressure, the push an RO purifier's pump must beat.
Downes and Blunt left test tubes of a nutrient liquid in the sun and others in the shade. The ones in sunlight stayed free of microbes. The part of sunlight that did the killing turned out to be ultraviolet light.
Why it mattered. It is the discovery behind the UV lamp inside many home purifiers.
Boltzmann showed that entropy measures how many ways the tiny particles of a thing can be arranged and still look the same from outside. Messy arrangements vastly outnumber tidy ones, so things drift towards mess. Max Planck later wrote it as S = k log W, around 1900, and that formula is carved on Boltzmann's grave in Vienna.
Why it mattered. It explained the second law using atoms, before most scientists believed atoms were real.
Eadweard MuybridgePalo Alto, California, United States
Muybridge lined up a row of cameras along a racetrack, each fired by a thread as the horse ran past. The sequence proved that all four hooves leave the ground at once. Shown quickly one after another, the still photos looked like motion.
Why it mattered. It showed that movement can be stored as a stack of still pictures, the idea every video still uses.
George Coy opened the first commercial telephone exchange, with 21 subscribers. His switchboard was built from carriage bolts and wire from ladies' bustles, and could connect two conversations at a time.
Why it mattered. For the first time you could call anyone on the exchange, not just one other phone.
Early operators were teenage boys, who were often rude to callers. Emma Nutt was hired as the first woman operator, and her sister Stella started a few hours later. Within a few years, switchboards everywhere were run by women.
Why it mattered. Operating the switchboard became one of the first big jobs open to women.
Eadweard Muybridge, for Leland StanfordPalo Alto, California, USA
Muybridge lined up a row of cameras beside a racetrack. Threads across the track fired the shutters one after another as the horse ran past, catching each phase of its stride.
Why it mattered. It proved that a camera could take movement apart, and showed that all four hooves leave the ground at once.
Leland Stanford wanted to know if a galloping horse ever has all four hooves off the ground. Muybridge lined up a row of cameras along a track, and the horse tripped their shutters one after another as it ran past. The pictures showed the answer was yes.
Why it mattered. It proved that a fast series of still photos can capture movement too quick for the eye to see.
Muybridge set up a row of cameras beside a track, each fired by a thread as the racehorse Sallie Gardner galloped past. The photographs showed that all four hooves leave the ground at once. He later projected his sequences with his own zoopraxiscope.
Why it mattered. It was the first time a fast motion was cut into a series of photographs, frame by frame.
Bert put animals and himself in steel chambers where he could lower the air pressure, as on a high mountain. In his book La pression barométrique he showed that altitude sickness comes from the low pressure of oxygen, not from low pressure itself, and that breathing extra oxygen helps. He also showed that too much oxygen can be poisonous.
Why it mattered. He is often called the father of high-altitude medicine.
Antonín DvořákPrague, Bohemia (now Czech Republic)
Dvořák wrote his Bagatelles for two violins, cello and harmonium. His friend's flat had no piano, only a harmonium, so he wrote for that. It was first played there in February 1879.
Why it mattered. It shows how common the harmonium was in European homes.
De Laval patented a separator that took in milk and let cream and skim milk flow out non-stop while it spun. With Oscar Lamm he founded AB Separator in 1883, now Alfa Laval. Dairies everywhere still separate cream this way.
Why it mattered. Continuous spinning made centrifuges practical for industry.
The earliest record of ‘geyser’ meaning a water heater, in the Oxford English Dictionary, is an 1878 advertisement for ‘Maughan's Patent Geyser’. The word comes from Geysir, a hot spring in Iceland whose name means ‘gusher’.
Why it mattered. A hot spring gave its name to a machine, and the name travelled across the British Empire to India.
Richard Leach Maddox, Charles Bennett and othersEngland
Gelatin dry plates, proposed by Maddox in 1871 and made much more sensitive by Bennett in 1878, could be bought ready-made and kept for months. Exposures dropped to fractions of a second.
Why it mattered. Cameras could now be held by hand, and needed real shutters.
Muybridge lined up twelve cameras with very fast shutters triggered as a galloping horse passed. The photos proved that all four hooves leave the ground at once.
Why it mattered. A fast shutter showed something the human eye had never been able to see. It pointed the way to cinema.
The anatomist Paul Broca noticed that the human olfactory bulb is small compared with the rest of our brain and grouped humans with the “non-smellers”. He did no smell tests. The idea that humans have a poor sense of smell stuck for over a century.
Why it mattered. Modern tests show human noses are far better than this old myth suggests.
The first public demonstration of electric light in India took place in Calcutta. Twenty years later, in 1899, the Calcutta Electric Supply Corporation opened the city's first power station.
Why it mattered. Electric light reached India within months of Edison's lamp.
Edison's team and Joseph Swan in England each made practical carbon-filament light bulbs. A good lamp gave people a reason to want electricity in every home.
Why it mattered. The light bulb created the demand for electricity supply.
Josef Stefan and Ludwig BoltzmannVienna, Austria-Hungary
Using Tyndall's measurements of a glowing platinum wire, Stefan found that the heat an object radiates grows with the fourth power of its absolute temperature. Double the temperature and the glow grows sixteen times. In 1884 his former student Boltzmann showed why this must be true.
Why it mattered. With it Stefan gave the first sensible estimate of the Sun's surface temperature, about 5,400 °C.
The Curie brothers found that squeezing certain crystals makes an electric voltage. This is called the piezoelectric effect. Pierre later became famous for his work on radioactivity with Marie Curie.
Why it mattered. The click of a gas lighter or hob knob is a tiny hammer hitting a crystal like this to make a spark.
Swiss-born engineer Hans Renold invented the bush roller chain, whose rollers turn on bushes to cut friction and wear. It became the chain used on almost every bicycle.
Why it mattered. A reliable chain made it possible to drive the rear wheel and choose any gear ratio.
Delegates from many countries agreed on practical electrical units, naming them after scientists: the volt, the ampere, the ohm, the coulomb and the farad.
Why it mattered. Engineers everywhere could now measure current and voltage the same way.
Planté's batteries took a long time to prepare. Faure pressed a paste of lead oxide into a lead grid, which held far more charge and was much quicker to make. Factories could now build lead-acid batteries in large numbers.
Why it mattered. Pasted plates descended from this idea are still inside many inverter batteries today.
Scientists from many nations agreed on the practical units of electricity, including the ohm. For decades after, the ohm was realised as a column of mercury about 106 cm long at 0 °C.
Why it mattered. A resistor made in one country could now be trusted in another.
After proving in 1876 that a bacterium causes anthrax, Koch announced that a rod-shaped bacterium causes tuberculosis, then the world’s biggest killer. His rules for proving that a germ causes a disease are still called Koch’s postulates.
Why it mattered. Each disease could now be traced to a specific cause, the first step to a specific cure.
Marey, a doctor who studied how animals move, built a chronophotographic gun that took 12 pictures a second, all from one viewpoint, to study birds in flight.
Why it mattered. Measuring motion from many timed pictures is exactly what a mocap camera still does, only faster.
Marey, a scientist who studied how animals move, built a chronophotographic gun. You aimed it like a rifle, and a spinning disc inside took 12 pictures in one second, all from a single lens. He used it to study birds in flight.
Why it mattered. One camera taking rapid pictures through one lens is the basic idea of every movie camera.
The scientist Marey built a chronophotographic gun that took 12 pictures a second on a rotating plate, to study birds in flight. He went on to record motion on strips of film.
Why it mattered. One camera, not a row of them, could now capture a sequence of moments.
Watching see-through starfish larvae under a microscope, Metchnikoff pushed rose thorns into them. The next morning, moving cells had crowded around the thorns. He named such cells phagocytes, “eating cells”, and argued they defend the body.
Why it mattered. It was the discovery of innate immunity: neutrophils and macrophages at work, like the splinter in chapter 2.
Tuberculosis was one of the biggest killers in the world. At a meeting of the Berlin Physiological Society, Koch showed the microbe that causes it, using more than 200 slides he had prepared. The date, 24 March, is now World TB Day.
Why it mattered. Knowing the cause made it possible to find TB, stop it spreading and, later, cure it, a fight that matters most of all in India.
Bizzozero showed that tiny discs in blood, which others thought were broken cells or even germs, are a separate part of blood. In living animals they were the first to stick to a damaged vessel wall and they started clots.
Why it mattered. Platelets are the first responders to every cut.
Tuberculosis was one of the biggest killers in the world. At a meeting of the Berlin Physiological Society, Koch showed the microbe that causes it, using more than 200 slides he had prepared. The date, 24 March, is now World TB Day.
Why it mattered. Knowing the cause made it possible to find TB, stop it spreading and, later, cure it, a fight that still matters most in India.
Edison's Pearl Street Station began supplying direct current (DC) to customers in lower Manhattan. DC could not easily be changed in voltage, so it only reached about a mile from the station.
Why it mattered. The start of electricity supplied from a central station.
William Soltau Davidson and the crew of the DunedinPort Chalmers, New Zealand, to London
The sailing ship Dunedin left New Zealand with nearly 5,000 frozen sheep and lamb carcasses, kept cold by a steam-driven Bell-Coleman refrigeration machine. It reached London 98 days later and the meat sold at Smithfield market. Within five years, 172 more shipments followed.
Why it mattered. It launched New Zealand's frozen meat trade and proved food could stay frozen across the planet.
Edison's Pearl Street Station began sending 110-volt direct current through cables under the streets of lower Manhattan. It started with 82 customers and 400 lamps. But low-voltage DC loses a lot of power in the wires, so it could only reach a short distance.
Why it mattered. It showed the problem that AC would solve, and DC is still what every battery stores.
Wheeler put a two-bladed propeller on an electric motor and made a desk fan. The same year Diehl adapted the motor from a Singer sewing machine to drive a fan on the ceiling.
Why it mattered. Electric fans brought cheap moving air into homes, and every air conditioner still has fans inside.
Wheeler, a young American engineer, put a two-bladed propeller on the shaft of an electric motor. The Crocker and Curtis company went on to sell electric fans in the 1880s.
Why it mattered. A motor plus a propeller is still the basic recipe of almost every fan.
Diehl, a German-born engineer who designed motors for Singer sewing machines, fixed a fan blade to one of those motors and hung it from the ceiling. He patented his “electric-motor fan” in 1889 and later added a light to it.
Why it mattered. It turned the water-and-belt ceiling fan into a self-contained machine you could hang in any room with electricity.
Marey dressed a man in black with thin white stripes and dots along his arms and legs, then photographed him walking and running in front of a black wall. Only the white lines showed, so each photo became a moving stick figure.
Why it mattered. Black suit, bright marks, dark background: it is the idea behind every optical marker suit today.
Working with the eggs of a roundworm that has very few chromosomes, Edouard van Beneden showed that the egg and the sperm each bring the same number of chromosomes, half of what the body's cells carry, and that they come together at fertilisation.
Why it mattered. This is the idea behind 23 + 23 = 46 in humans.
Ringer found that a frog heart kept beating in London tap water but stopped in distilled water. The missing ingredient was calcium: without it the heart muscle could not contract.
Why it mattered. Calcium, it turned out, is the switch that turns every muscle on.
Testing railway axle bearings for the Institution of Mechanical Engineers, Tower drilled a hole in a bearing and plugged it. The plug kept being forced out by the oil. He measured the pressure and found that the oil film itself was carrying the load.
Why it mattered. It revealed hydrodynamic lubrication: a shaft can float on oil.
A company began pumping water at about 800 psi (55 bar) through cast-iron mains under London's streets. Customers used it to run lifts, cranes, dock gates and even theatre stages.
Why it mattered. Pascal's principle carried the pressure, and so the power, through miles of pipe.
Reynolds let a thin thread of dye into water flowing through a glass pipe. At low speed it stayed a neat line; faster, it suddenly broke into swirls. The switch depends on speed × width ÷ viscosity, a ratio later named the Reynolds number.
Why it mattered. It explained when friction in pipes changes its behaviour.
James Thomson, an engineer and the elder brother of Lord Kelvin, used 'torque' in print in 1884, from the Latin torquere, to twist. Silvanus Thompson took it up the same year in his book on dynamos.
Why it mattered. Engineers finally had a short word for a twisting force.
Hugo de Vries dipped plant cells in solutions of different strengths and watched under the microscope. In strong ones the living contents pulled away from the cell wall, which he called plasmolysis. By finding the strength that just started it, he could compare how hard different substances pulled. He called solutions that balanced a cell isotonic.
Why it mattered. He showed that living cells obey the same osmosis rules as clay pots, and his data helped van 't Hoff.
Applied 6 January 1884, granted 15 January 1885 · No. 014 TVClear
A spinning disc full of holes
Paul NipkowBerlin, Germany
A 23-year-old student in Berlin patented an “electric telescope”. Its heart was a disc with a spiral of small holes. As the disc spun, each hole swept across one thin strip of the picture, so the whole image was read line by line.
Why it mattered. Breaking a picture into lines, one after another, is still how every TV picture is built.
Waterman patented a feed with fine channels that let ink out by capillary action while letting air in, so the pen stopped blotting. The popular story that a leaking pen cost him a contract may be a legend.
Why it mattered. Balancing ink out and air in is still how every fountain pen works.
Lala Deen Dayal set up studios in India and became court photographer to the Nizam of Hyderabad. His thousands of glass-plate negatives record late 19th-century India.
Why it mattered. He's one of the most celebrated early photographers in India.
Pasteur found that old, weakened chicken cholera germs protected hens (1879). He made an anthrax vaccine for sheep (1881), and on 6 July 1885 his team gave a rabies vaccine to nine-year-old Joseph Meister, who had been bitten by a rabid dog. He survived.
Why it mattered. Pasteur showed vaccines could be made on purpose in the lab by weakening a germ.
Gottlieb Daimler and Wilhelm MaybachBad Cannstatt, Germany
Daimler and Maybach needed a test bed for their new small, fast-running petrol engine. They put it in a wooden frame with two wheels and two small outrigger wheels. Daimler's 17-year-old son Paul rode it about 5 km, at up to 11 km/h. Its single cylinder made about half a horsepower.
Why it mattered. It is widely recognised as the first motorcycle with a petrol engine, the kind every commuter bike still uses.
Rufus Eastman is thought to have invented the first mixer driven by an electric motor. Few homes had electricity yet, so electric mixing stayed rare for decades.
Why it mattered. It swapped the tired human arm for a motor, the step every electric kitchen machine depends on.
Károly Zipernowsky, Ottó Bláthy and Miksa Déri; William StanleyGanz factory, Budapest, Hungary; Great Barrington, USA
At the Ganz works in Budapest, three engineers built efficient transformers with closed iron cores, known as the ZBD transformer. In March 1886 William Stanley, backed by George Westinghouse, used ideas from these designs to run a demonstration AC lighting system in Great Barrington, Massachusetts.
Why it mattered. Transformers let AC be sent at high voltage and stepped down safely, which DC could not do.
Gottlieb Daimler and Wilhelm MaybachCannstatt, Germany
After leaving Deutz, Daimler and Maybach built a light, fast-running petrol engine nicknamed the ‘grandfather clock’. In 1885 they put it on a wooden two-wheeler, the Reitwagen, often called the first motorcycle. In 1886 they fitted a stronger version to a horse carriage, making one of the first four-wheeled motor cars.
Why it mattered. Their small high-speed engine showed that petrol engines could be light enough to power almost anything.
Károly Zipernowsky, Ottó Bláthy and Miksa DériGanz Works, Budapest
Three engineers at the Ganz factory wound coils on a closed iron core, just like Faraday's ring, and got efficient transformers. They were shown at the Budapest National Exhibition in 1885.
Why it mattered. Transformers let power travel far at high voltage and arrive safely at low voltage, which is why homes use AC.
Starley's Rover had two wheels of similar size, a chain driving the rear wheel, and a steerable front with the rider sitting between the wheels. Gearing replaced the giant wheel, so it was fast and much safer.
Why it mattered. It's the basic shape of almost every bicycle since.
A priest who believed cold baths in the Danube had helped him recover from tuberculosis wrote 'Meine Wasserkur'. It taught cold affusions, walking barefoot in wet grass, herbs, exercise and simple food, and was translated into many languages.
Why it mattered. Kneipp's book made nature cure a household idea, and his 'five pillars' still shape spa therapy.
Anandibai Joshi and Kadambini GangulyPhiladelphia, USA, and Calcutta, India
Anandibai Joshi earned a medical degree from the Woman’s Medical College of Pennsylvania in March 1886, and Kadambini Ganguly graduated from Calcutta Medical College the same year and went on to practise for decades. Both faced fierce opposition for wanting to become doctors.
Why it mattered. They opened modern medicine to Indian women, at a time when many families would not let a male doctor examine a woman.
Anandibai Joshi lost her baby son days after birth, and resolved to study medicine. She sailed to the United States and graduated from the Woman's Medical College of Pennsylvania with a thesis on obstetrics among Hindus.
Why it mattered. She showed Indian women could become doctors, and she chose care for mothers and babies as her subject.
Reynolds explained Tower's result: a turning shaft drags oil into the narrowing gap of its bearing, building enough pressure to lift the shaft off the metal. His equation is still used to design engine bearings.
Why it mattered. It turned lubrication from guesswork into engineering.
Joly calculated the pressure under a skate blade at about 466 atmospheres, enough to lower ice's melting point by about 3.5 °C. For decades this pressure-melting idea was the textbook reason skates glide.
Why it mattered. It explained skating near 0 °C, but not why skating works at −20 °C.
Jacobus Henricus van 't HoffAmsterdam, Netherlands
Using Pfeffer's and de Vries's numbers, van 't Hoff showed that a dissolved substance pushes on a membrane with exactly the pressure it would have as a gas in the same space: π = MRT. Salts pushed more than expected, and he added a factor i to count that. Svante Arrhenius soon explained why: salts split into ions.
Why it mattered. It tied osmosis to the gas laws and helped found physical chemistry.
Josephine Cochrane and George ButtersShelbyville, Illinois, USA
Cochrane's heirloom dishes kept getting chipped in the washing up, so she designed a better way. Wire compartments held plates, cups and saucers on a wheel inside a copper boiler, and hot soapy water squirted up from below and rained down on them. With the mechanic George Butters she built it in a shed and won US patent 355,139.
Why it mattered. It was the first dishwasher to clean with the force of water instead of scrubbers, the idea every dishwasher still uses.
Using Pfeffer's numbers, the Dutch chemist Jacobus van 't Hoff showed that dissolved substances push on a membrane much like a gas pushes on a container. The more stuff dissolved, and the warmer it is, the bigger the push. In 1901 he won the very first Nobel Prize in Chemistry, partly for this work.
Why it mattered. His law tells engineers how hard they must push salty water to force it backwards through a membrane.
Benz applied for German patent number 37435 for a ‘vehicle powered by a gas engine’. His Patent-Motorwagen had three wheels, a single-cylinder petrol engine at the back, electric ignition and a chain drive. Unlike earlier attempts, the engine and the carriage were designed together as one machine.
Why it mattered. The Mercedes-Benz Group calls this patent the birth certificate of the automobile.
William Stanley Jr.Great Barrington, Massachusetts
Stanley, working for George Westinghouse, sent alternating current along the main street at high voltage and used transformers to step it down for the shops and offices.
Why it mattered. It was the first complete system of generator, transformers and high-voltage AC line.
Felt patented the Comptometer, a key-driven adding machine: pressing a key in a column added that digit at once, with no crank to turn. Skilled operators, many of them women, added long columns of figures astonishingly fast, and Comptometers stayed in offices until the 1970s.
Why it mattered. It made calculating a matter of pressing keys, the way we still use calculators today.
Augustus WallerSt Mary's Hospital, London, England
Waller used a capillary electrometer, a thin tube of mercury that twitches with electric current, to record a human heartbeat from the outside of the body. The trace was faint and blurry. Later he even recorded his dog Jimmy standing in bowls of salty water.
Why it mattered. It proved the heart's electrical signal can be picked up on the skin, the idea behind every ECG.
With a spark gap and a loop of wire, Hertz sent and detected invisible electromagnetic waves across his lab. He reflected them off a metal sheet to make standing waves a few metres long, and showed they travel at the speed of light.
Why it mattered. It proved Maxwell right and opened the way to radio, TV, Wi-Fi and microwave ovens. The unit of frequency is named after him.
Ellen Swallow Richards, the first woman admitted to MIT, tested about 40,000 water samples for the Massachusetts Board of Health. She drew a 'normal chlorine' map showing how much salt the water naturally had in each place. Extra salt pointed to sewage pollution.
Why it mattered. Her work led to the first water-quality standards in the United States.
Hertz made sparks jump across a gap and found that a small loop of wire across the room sparked too. Invisible waves were crossing the room. He showed they bounce and bend like light, just as Maxwell had predicted.
Why it mattered. It proved electromagnetic waves were real, and the unit of frequency, the hertz, is named after him.
Hertz noticed that a spark in one coil made a tiny spark jump in another nearby. He went on to show these were Maxwell's waves, travelling through the air and behaving like light. He published from November 1887.
Why it mattered. Maxwell was right, and radio, TV and Wi-Fi all follow from it.
Clemens HerschelHolyoke Water Power Company, Massachusetts
Herschel built a pipe with a gentle neck and read the flow from the pressure drop across it. He tested it from 1886, filed a patent in December 1887 and named it after Venturi. The patent was granted in April 1888.
Why it mattered. Water companies used it to measure huge flows with no moving parts.
Le Prince, a French inventor living in Leeds, used his single-lens camera to film family and friends walking in a garden at Roundhay. The clip lasts only about two seconds, yet it is often called the oldest surviving motion picture. In 1890 Le Prince boarded a train to Paris and was never seen again.
Why it mattered. He made working moving pictures years before the famous names, a reminder that 'firsts' are often disputed.
Le Prince filmed his family walking in a garden with his single-lens camera. The Roundhay Garden Scene lasts about two seconds. In 1890 he vanished from a train before he could show his work in public, and was never seen again.
Why it mattered. It is widely considered the oldest surviving motion picture.
Using and improving Golgi’s stain, Cajal showed that nerve cells are separate units that touch but do not join, and that signals flow one way through them. In 1906 the two men shared a Nobel Prize, though Golgi still thought the nerves formed one continuous net.
Why it mattered. The neuron doctrine is the foundation of all brain science.
Gee, a London children's doctor, described children with pale, bulky stools, swollen bellies and poor growth in a paper called On the coeliac affection. He guessed that diet was the key to treating it. He did not yet know which food was to blame.
Why it mattered. It gave the disease a clear modern description, the starting point for finding its cause.
Zwaardemaker built a device with a glass tube that slid inside a tube lined with a smelly material. Sniffing through it, a person got a stronger smell the further the tube was pulled out, so the weakest detectable smell could be measured.
Why it mattered. For the first time, the strength of a smell and a person’s sensitivity could be put into numbers.
Fick made a glass shell that sat on the white of the eye over the cornea, tried it on rabbits, then on himself and a few volunteers, and published it as a "Contactbrille".
Why it mattered. Contact lenses now correct the sight of well over a hundred million people.
Using an improved version of Golgi’s stain, Cajal showed that nerve cells are separate units that nearly touch, not one continuous net. His thousands of drawings still appear in textbooks.
Why it mattered. The neuron doctrine is the foundation of modern neuroscience.
Thomas Edison vs George Westinghouse and Nikola TeslaUnited States
Westinghouse backed alternating current (AC), using transformers to send high voltages far and step them down for homes, and bought Nikola Tesla's AC motor patents in 1888. Edison campaigned that AC was deadly. AC lit the 1893 Chicago World's Fair and in 1895–96 carried power from Niagara Falls to Buffalo.
Why it mattered. It is why the socket in your wall gives AC.
Galileo Ferraris and Nikola TeslaTurin and New York
Ferraris demonstrated a rotating-field motor in 1885 and Tesla, working independently, was granted his induction motor patents in May 1888. A rotating magnetic field drags the rotor round with a steady torque, as in a ceiling fan today.
Why it mattered. Electric torque began to replace belts and steam in factories and homes.
Dunlop, a vet, wrapped an inflated rubber tube around the wheels of his son's tricycle for a smoother ride. His patent later turned out to be invalid, because Robert William Thomson had patented a pneumatic tyre in 1847. Dunlop's tyre still took over bicycles and then cars.
Why it mattered. Air pressure became the thing that holds up bicycles, cars and aircraft on the ground.
Working for Westinghouse, Shallenberger noticed a loose spring turning in the magnetic field of an AC lamp. He turned the idea into a meter that measured how much alternating current a customer used. About 120,000 were sold within ten years.
Why it mattered. Homes could now be charged for the energy they used, not a flat fee per lamp.
Nikola Tesla and Galileo FerrarisNew York, USA, and Turin, Italy
Tesla, a Serbian-American engineer, was granted US patents for motors driven by a rotating magnetic field made from AC. In Italy, Galileo Ferraris had built a similar motor on his own. In July 1888 George Westinghouse paid to license Tesla's patents.
Why it mattered. Once AC could run motors as well as lights, it had everything it needed to win the grid.
Bradley's rotary converter was a spinning machine that took in AC and gave out DC for trams, trains and factories. Run the other way, such machines could turn DC into AC. That is where the word ‘inverter’ comes from: an inverted converter.
Why it mattered. For half a century, turning one kind of current into the other meant a big machine spinning in a room.
Without telling her husband Karl, Bertha Benz drove the Motorwagen about 106 km to her mother's town, with her two teenage sons. She bought fuel at a pharmacy in Wiesloch, cleared a blocked fuel line with her hatpin, and had a cobbler fit leather to the brakes. On steep hills the boys had to push, because the car's two gears were not low enough.
Why it mattered. Her trip showed the public that a motor car really worked, and helped bring the Benz company its first sales.
Galileo Ferraris and Nikola TeslaTurin, Italy; New York, USA
Ferraris in Turin and Tesla in New York each made a magnetic field that rotates. It induces currents in a metal rotor, which chases the field round with no sliding contacts. Ferraris published in April 1888 and Tesla's patents were granted in May 1888.
Why it mattered. Induction motors now spin most fans, pumps, washing machines and factory machines.
For years many pianos had 85 keys, seven octaves from A to A. In the late 1880s Steinway built pianos with 88 keys, from A0 to C8, and other makers followed. By the early 1900s 88 keys was the standard around the world.
Why it mattered. 88 keys covers almost every note an orchestra can play.
Tesla was granted patents for a motor with no brushes, driven by a magnetic field that spins as alternating current flows through its coils. Galileo Ferraris in Italy worked out the same idea independently. George Westinghouse bought the rights to Tesla's patents in 1888.
Why it mattered. The induction motor had no sparking brushes to wear out, and it went on to power most fans for more than a century.
Dunlop, a vet, made air-filled tyres for his son's tricycle to smooth out bumpy roads, and patented them. Robert William Thomson had patented a pneumatic tyre in the 1840s, but it hadn't caught on.
Why it mattered. Comfort and speed together. Pneumatic tyres went on to every car.
Loud, a leather tanner, patented a pen with a small rotating steel ball held in a socket, for marking rough surfaces like leather. It was too coarse for writing letters and the patent lapsed.
Why it mattered. The rolling ball worked, but the right ink was still fifty years away.
Gray's telautograph used a pen connected to linkages that turned its movements into electrical signals. A second pen, miles away, copied the writing as it happened.
Why it mattered. An ancestor of the fax machine and of the digital stylus.
The first Kodak came loaded with a roll for 100 pictures. When it was full, you mailed the whole camera back to Kodak, which developed the prints and reloaded the camera. A year later, Eastman switched to transparent celluloid film.
Why it mattered. Anyone could take photographs without knowing any chemistry.
Joseph von Mering and Oskar MinkowskiStrasbourg (then Germany, now France)
Von Mering and Minkowski removed the pancreas from a dog to study digestion. The dog began to pass large amounts of urine full of sugar, just like a person with diabetes. The pancreas was doing something to control sugar.
Why it mattered. It pointed the hunt for a diabetes treatment at the pancreas.
Oskar Minkowski and Joseph von MeringStrasbourg (then Germany, now France)
Studying digestion, Minkowski and von Mering removed a dog's pancreas. The dog soon passed large amounts of urine full of sugar: it had diabetes. A popular story says flies around the urine gave it away, but that detail may be legend.
Why it mattered. It proved that the pancreas controls blood sugar, and started the hunt for the substance it makes.
Joseph Kekuku said that as a schoolboy in Honolulu he picked up a bolt and slid it along his guitar strings. He refined the trick with a polished steel bar, playing with the guitar flat on his lap. He took this Hawaiian steel guitar on tours of America and Europe.
Why it mattered. Sliding a bar instead of pressing frets gave the guitar a gliding, singing voice that later travelled to India.
Ruud, a Norwegian engineer who had moved to Pittsburgh, designed an automatic gas water heater with a storage tank. Metal rods that grew longer as they warmed worked a valve, turning the gas flame down when the water was hot and up when it cooled. He later founded the Ruud Manufacturing Company.
Why it mattered. A tank of water kept hot by its own switch is the plan of almost every storage water heater since.
Meeting during the Paris World's Fair, the congress adopted the joule for work and the watt, one joule per second, for power. Joule died in October that year, weeks after his unit became official.
Why it mattered. Scientists and engineers everywhere could now use the same words for work and power.
Bláthy's induction meter, shown at the Frankfurt Fair, used a spinning disc to add up power over time and show kilowatt-hours. The same principle ran most electricity meters for the next hundred years.
Why it mattered. The kilowatt-hour became the unit on every electricity bill.
1st General Conference on Weights and MeasuresSèvres, near Paris, France
The conference approved the International Prototype of the Kilogram: a cylinder of 90% platinum and 10% iridium, 39 mm high and 39 mm across, kept in a vault near Paris. For 130 years a kilogram was, by definition, its mass.
Why it mattered. Every scale in the world was traceable to one metal cylinder.
Loránd Eötvös, with Dezső Pekár and Jenő FeketeBudapest, Hungary
With a delicate torsion balance, Eötvös checked whether materials with the same weight also have the same inertia. By 1890 he found no difference to about 5 parts in 100 million; long runs with Pekár and Fekete from 1906 to 1908, published in 1922, pushed that to a few parts in a billion.
Why it mattered. It showed inertial and gravitational mass are the same to astonishing accuracy.
Thorp and Marsh patented a practical coin-in-the-slot gas meter. Families could drop in a penny and get a little gas, with no big bill. In 1898 gas engineers reported that working-class homes that had rarely used gas now used much more.
Why it mattered. Paying in small amounts helped gas reach poorer homes, much like buying one LPG cylinder at a time.
Following an idea put forward by the engineer William Siemens in 1882, an international congress adopted the joule as a unit of energy, along with the watt. One joule is roughly the energy needed to lift an apple one metre. Joule himself died that October.
Why it mattered. Every kind of energy, from food to lightning, can now be measured in the same unit.
Emil von Behring and Kitasato ShibasaburōBerlin, Germany
Von Behring and the Japanese scientist Kitasato showed that the blood serum of animals that survived tetanus or diphtheria could neutralise the germ’s poison and protect other animals. Serum therapy soon saved many children with diphtheria.
Why it mattered. It revealed antibodies in the blood, and it won the first Nobel Prize in medicine in 1901.
Dhobi Ghat in Mumbai was built in 1890, when the city was under British rule. Rows of open concrete wash pens each have a flogging stone, where washers called dhobis soak, beat and rinse clothes by hand. It is still working today, and more than 100,000 pieces of clothing are washed there every day.
Why it mattered. Washing by hand with water, soap and muscle is the oldest method of all, and for many people it is still how laundry gets done.
Kuhne's 'Die neue Heilwissenschaft' (The New Science of Healing) claimed that every illness is one thing, a build-up of 'foreign matter'. His cure: cold hip and friction sitz baths at about 10 to 14 °C, steam baths and a raw vegetarian diet.
Why it mattered. His 'unity of disease' idea and his hip bath became the backbone of Indian nature cure.
Almon Strowger, an undertaker, patented an automatic stepping switch. The story goes that he believed a local operator was sending his customers' calls to a rival. In his switch, electrical pulses from the caller move a wiper up and round to the right line.
Why it mattered. It began the end of manual switchboards: the exchange could now count the number itself.
William Kennedy Dickson and Thomas Edison's teamWest Orange, New Jersey, USA
Dickson led the work at Edison's laboratory on a camera called the Kinetograph and a peep-show viewer called the Kinetoscope. An electric motor pulled a strip of perforated film past the lens, stopping it for each picture. By 1893 they had built the Black Maria, a film studio that could turn to follow the sun.
Why it mattered. Their strip of film, about 35 mm wide with holes along the edges, became the shape of cinema for the next century.
George Redmayne MurrayNewcastle upon Tyne, England
A 46-year-old woman had myxoedema: her thyroid was failing, and she was slow, cold and puffy. George Murray injected her with an extract of sheep thyroid, and within months she was much better. She kept taking it and lived to 74.
Why it mattered. It was one of the first times a missing hormone was replaced, an idea still used by millions today.
Kemp patented a solar water heater made of iron tanks inside a glass-topped box on the roof. Sunlight passed through the glass, and the box kept the wind from stealing the heat. Sold as the Climax, it became popular in sunny southern California: by 1897 about a third of homes in Pasadena used one.
Why it mattered. It was the world's first commercial solar water heater.
Westinghouse built small alternating-current induction motors to drive fans. A Westinghouse fan motor at the Smithsonian still carries a nameplate listing Tesla's patent.
Why it mattered. Fans were one of the first everyday machines to use the new AC motor.
The first commercial automatic exchange, using Strowger's switch, opened in La Porte. Early callers pressed buttons to send the pulses; the finger-wheel rotary dial followed over the next years.
Why it mattered. A small town showed that a phone network could run without operators.
Reynaud’s Théâtre Optique projected long strips of hand-painted pictures, with a separate background, for paying crowds. Pauvre Pierrot and two other films opened the show, which ran until 1900 and drew over 500,000 visitors.
Why it mattered. It was the first public show of projected animated pictures, three years before the Lumière brothers’ films.
Wolff, a Berlin surgeon, published The Law of Transformation of Bone. It says the shape and inner struts of a bone change to match the forces put on it. Use a bone more and it grows stronger. Leave it unused and it thins.
Why it mattered. Wolff's law is why exercise builds bone and astronauts lose it.
Using a silver stain, Cajal drew the retina's layers of rods, cones, bipolar cells and ganglion cells and argued that signals flow from one cell to the next in a set direction.
Why it mattered. His drawings are still used to teach how the retina is wired.
Dewar needed to keep liquefied gases extremely cold, so he made a glass vessel inside another with a vacuum between them. With no air in the gap, heat cannot cross by conduction or convection, and a silvered coating cuts down radiation. Dewar never patented it, and in 1904 two German glassblowers, Reinhold Burger and Albert Aschenbrenner, sold it as the Thermos.
Why it mattered. One simple object blocks all three ways heat moves, which is why your flask keeps chai hot for hours.
Emerson, founded in 1890, began selling electric fans in 1892. Makers such as Emerson, Westinghouse and General Electric soon filled offices and shops with desk and ceiling fans.
Why it mattered. Fans became one of the first electric appliances people bought for everyday comfort.
Thomas Edison's laboratory; W. K. L. DicksonWest Orange, New Jersey
Early film needed a huge amount of light, so Edison's team built the Black Maria, a tar-papered studio with a roof that opened to the sky. The whole building sat on a turntable and was turned to face the sun as it moved. It cost $637.67 to build.
Why it mattered. The first film lighting was simply daylight, steered by turning the building.
Thomas Edison's laboratory; W. K. L. DicksonWest Orange, New Jersey
Dickson and his team built the Kinetoscope, a cabinet in which one person at a time watched a loop of 35 mm film. To make films for it they built the Black Maria, a tar-papered studio that turned to follow the sun. Kinetoscope parlours opened in 1894.
Why it mattered. It set the 35 mm film width, with holes along the edges, that cinema used for a century.
Built for the World's Columbian Exposition, Ferris's wheel stood 80 m high with 36 cars that each held up to 60 people. It turned slowly, about 9 minutes for a non-stop turn, so riders barely felt the circle.
Why it mattered. It started the giant wheels found at every mela and fair.
Josephine CochraneWorld's Columbian Exposition, Chicago, USA
Nine of Cochrane's machines washed dishes in the restaurants and pavilions of the huge Chicago fair. Her machine won a prize for ‘best mechanical construction, durability and adaptation to its line of work’. Restaurants and hotels took notice.
Why it mattered. The fair turned a clever idea into a business with real customers.
George Westinghouse and Nikola TeslaWorld's Columbian Exposition, Chicago, USA
Westinghouse won the contract to light the Chicago World's Fair with alternating current, underbidding General Electric. By some counts about 200,000 lamps glowed across the grounds. Tesla showed his motors and generators at the Westinghouse exhibit.
Why it mattered. Millions of visitors saw that AC could light a whole city safely.
Diesel, born in Paris to German parents, patented an engine that squeezes air so hard it gets hot enough to light the fuel by itself. His German patent dates from 1892–1893. After years of work at the Augsburg machine works, a test engine ran successfully in 1897.
Why it mattered. Diesel engines are very efficient and still move most of the world's trucks, ships and trains.
Maybach's carburettor put a fuel jet in the narrow throat where the engine's incoming air is fastest. The low pressure there sprays petrol into the air in step with how hard the engine breathes. In Hungary, Donát Bánki and János Csonka patented a carburettor the same year.
Why it mattered. Most petrol engines used this idea for about a century, until fuel injection took over.
Kuhne's book was translated into Telugu, one of its earliest translations into an Indian language. Nature cure groups grew in Andhra, Bengal, Gujarat, Maharashtra and Uttar Pradesh.
Why it mattered. Indian naturopathy counts this translation as its starting point.
George Oliver and Edward SchäferUniversity College London, England
The story goes that George Oliver, a country doctor, gave adrenal extract to his son and noticed a change in his pulse. He took it to Edward Schäfer in London. When they injected it into a dog, the blood pressure shot up.
Why it mattered. It showed that the adrenal glands release a powerful substance into the blood.
Junkers had built a calorimeter, a device that measured how much heat a gas gave off by warming flowing water. He used the same idea to make a gas bath heater, then refined it into a heater that warmed water as it flowed. In 1895 he founded Junkers & Co. to make them.
Why it mattered. Heating water only as it flows, with no tank, is how instant gas and electric geysers still work.
Heinrich and Wilhelm Hildebrand, Alois WolfmüllerMunich, Germany
Hildebrand & Wolfmüller sold the first motorcycle made in series, and they were the first to call it a Motorrad, 'motor wheel'. Its 1,489 cc two-cylinder engine made about 1.9 kW and drove the back wheel directly. About 2,000 were built.
Why it mattered. For the first time, you could simply buy a motorcycle.
Sir W. G. Armstrong, Mitchell and Co.London, England
Tower Bridge opened with its two bascules, each weighing over 1,000 tonnes, raised by hydraulic engines. Steam pumps charged six accumulators with water at about 750 psi, and the stored pressure drove the machinery. The water system worked until 1974, when oil and electric motors replaced it.
Why it mattered. A landmark still moved by the principle that moves a car's brakes.
Röntgen noticed a screen glowing across his dark lab while he worked with a cathode-ray tube. The invisible rays passed through paper, wood and flesh but not bone. Within weeks, doctors were using X-rays to find bullets and broken bones.
Why it mattered. It began medical imaging, which now includes CT and MRI scans.
The Lumière brothers patented a machine that could film, print and project moving pictures. It was a hand-cranked wooden box that pulled the film along with a claw, one frame at a time. It ran at about 16 frames each second, which became the usual speed of early silent films.
Why it mattered. Moving the film in short, exact steps, not smoothly, is the trick that makes still frames look like motion.
Auguste and Louis LumièreSalon Indien, Grand Café, Paris
In a basement room of the Grand Café in Paris, the Lumières showed ten short films to a paying audience of about thirty people. Within weeks, crowds of up to 2,500 a day queued to get in. It is widely seen as the birth of cinema as a paid show, though others, like the Eidoloscope in New York, had shown films for money a few months earlier.
Why it mattered. A projector and a big screen let many people share one film, which is what made cinema a business.
Cinema pianists, organists and orchestrasCinemas worldwide
From the first public film shows in the 1890s, films were usually accompanied by live music: a pianist, an organ or a small orchestra. Some halls added a person making sound effects, and in India and Japan live narrators explained the story.
Why it mattered. Audiences already expected sound with pictures, long before films could carry it.
Alfred Clark, for the Edison Manufacturing CompanyEdison company, New Jersey
The Execution of Mary Stuart lasts about 18 seconds. Just before the axe falls, the camera was stopped, the actor was swapped for a dummy, and filming started again. On screen the swap is invisible.
Why it mattered. It is the first known film to use a special effect, the stop trick or substitution splice.
The Lumière brothers patented a hand-cranked box that could film, print and project. A small claw pulled the film down one frame at a time while a shutter hid the movement. On 28 December 1895 they showed ten short films to a paying audience in a Paris café, a date widely treated as the birth of cinema.
Why it mattered. It turned moving pictures from a peep show into something a whole room could watch together.
The Lumière brothers' Cinématographe could film, print and project. In a basement room of a Paris café they showed ten short films to a paying audience, including workers leaving their factory.
Why it mattered. It is widely counted as the birth of cinema: many people watching one big projected picture together.
Wilhelm Röntgen and Anna Bertha RöntgenWürzburg, Germany
Six weeks after discovering a new kind of ray, Röntgen photographed his wife Anna Bertha's hand with it. The picture showed her finger bones and her wedding ring. She is reported to have said, I have seen my death.
Why it mattered. For the first time, doctors could see bones inside a living person without cutting.
Röntgen discovered a new kind of invisible ray that passes through soft flesh but not bone, and made a picture of the bones in his wife’s hand. Within months doctors were using X-rays.
Why it mattered. The chest X-ray became a key way to see lung disease such as TB and pneumonia.
For his doctoral thesis Pierre Curie measured how magnetism changes with temperature. He found that iron and other ferromagnets lose their strong magnetism above a certain temperature, now called the Curie point: 770 °C for iron.
Why it mattered. It showed that magnetism depends on the order of atoms, which heat can scramble.
Lina Beecher; Edwin PrescottConey Island, New York, USA
The Flip Flap Railway at Sea Lion Park had a perfectly circular loop, and riders complained of neck injuries from the high g-force. In 1901 Prescott's Loop the Loop used a taller, teardrop-shaped loop to ease it.
Why it mattered. Engineers learned that a round loop is the worst shape for riders.
Röntgen noticed a glowing screen across his lab while working with a cathode-ray tube, and found invisible rays that passed through card, wood and flesh but not bone. Within weeks doctors were taking X-ray pictures around the world. (How X-rays are made and stopped is the story of XRayClear.)
Why it mattered. Every CT scanner still starts with the same kind of ray, just measured far more carefully.
Röntgen covered a cathode ray tube in black cardboard and darkened his lab. A screen painted with a glowing chemical lit up across the room. Something unknown was passing through the cardboard, so he called it X, the letter for an unknown.
Why it mattered. It was the discovery of a new kind of ray that could pass through things that block light.
Anna Bertha Röntgen and Wilhelm RöntgenWürzburg, Germany
Röntgen asked his wife Anna Bertha to hold her hand on a photographic plate while the rays shone through it. The picture showed the bones of her fingers and a dark ring on one of them. She is said to have exclaimed that she had seen her own death.
Why it mattered. It became the most famous image of the age and showed at once what X-rays could do for medicine.
Röntgen handed in a short paper describing the rays to the Würzburg Physical-Medical Society. He mailed copies and X-ray pictures to other scientists on New Year's Day. Newspapers carried the story around the world within weeks.
Why it mattered. Because he shared everything fast and freely, labs everywhere could build their own machines.
Jagadish Chandra BosePresidency College, Calcutta (today Kolkata), India
Bose built his own transmitter, horn antennas and detectors for waves only millimetres long, at about 60 GHz. In a public demonstration he sent them 23 m, through two walls, to ring a bell and set off a little gunpowder. An IEEE Milestone plaque now honours the work.
Why it mattered. He showed that very short radio waves could be made, aimed and detected, decades before radar.
Annie LondonderryBoston, USA, and around the world
Annie Cohen Kopchovsky, riding as “Annie Londonderry”, set off from Boston and returned about fifteen months later, having travelled around the world by bicycle and steamship.
Why it mattered. Widely called the first woman to cycle around the world, at a time when women riding at all was controversial.
Just published 'Kehrt zur Natur zurück!' and ran the Jungborn centre, where patients slept outdoors and used wet earth packs, light, air and a vegetarian diet.
Why it mattered. His book taught Gandhi mud treatment, which became a staple of Indian naturopathy.
Thomas Armat, Charles Francis Jenkins and Thomas EdisonKoster and Bial's Music Hall, New York
Armat and Jenkins built a projector called the Phantoscope. Edison's company agreed to make it, but only if it was sold as a new Edison invention, the Vitascope. Its first theatre show was at Koster and Bial's Music Hall in New York.
Why it mattered. It brought projected films to American theatres, and showed how much a famous name could sell a machine.
Marius Sestier, for the LumièresWatson's Hotel, Bombay
Just six months after Paris, the Lumière operator Marius Sestier showed six short films at Watson's Hotel in Bombay, now Mumbai. It was the first time moving pictures were shown in India. A second show followed a week later at the Novelty Theatre.
Why it mattered. The projector carried cinema around the world in a suitcase, and India would go on to make more films than any other country.
Oskar Messter, Max Gliewe and Robert W. PaulBerlin, Germany, and London, England
Projectors began to use the Geneva drive, or Maltese cross: a wheel with four slots that is nudged a quarter turn by a pin, then held still. The first uses in projectors date to 1896, in machines by Oskar Messter and Max Gliewe in Germany and in Robert W. Paul's Theatrograph in London. Each turn moves the film exactly one frame, then locks it steady while it is lit.
Why it mattered. Almost every film projector for the next hundred years used this clever star-shaped wheel.
Méliès said his camera jammed while filming a Paris street. When he projected the film, a bus seemed to turn into a hearse. He began stopping the camera and splicing film on purpose to make things appear and vanish.
Why it mattered. It showed that film could be cut and joined to change what the audience believes they saw.
Méliès was a stage magician who fell in love with film. By his own account, his camera jammed while filming a street, and when he played the film back a bus seemed to turn into a hearse. He turned the accident into the stop trick: stop the camera, change something, start again.
Why it mattered. It showed that film does not have to show reality, which is the whole idea behind visual effects.
Georges Méliès; Jehanne d'AlcyMontreuil-sous-Bois, near Paris
Stage magician Georges Méliès filmed a trick where a woman under a cloth vanishes and a skeleton appears. He used the substitution splice instead of a trapdoor. Méliès later said he found the trick when his camera jammed, but historians think he probably saw it in an Edison film first.
Why it mattered. Méliès turned a simple camera trick into a way of doing real magic on film.
Méliès built a glass-walled studio in his garden so that sunlight could flood in for filming. Inside he built painted sets, trapdoors and stage machinery, just like a theatre.
Why it mattered. It was one of the first buildings made for creating film effects on purpose.
Marius Sestier, for the Lumière companyWatson's Hotel, Bombay (now Mumbai), India
Only about six months after Paris, a Lumière agent showed six short films at Watson's Hotel in Bombay. Tickets cost one rupee. More shows followed within days at the Novelty Theatre.
Why it mattered. India met cinema almost as early as Europe did, and soon began making its own films.
Starling showed that blood pressure pushes fluid out of capillaries while the proteins in plasma pull it back by osmosis. The balance of these Starling forces decides whether tissues stay just moist or swell.
Why it mattered. It explains swelling (oedema) and why the lymph is needed.
Riva-Rocci wrapped an inflatable cuff around the upper arm and read the pressure on a column of mercury. When the pulse at the wrist vanished, the cuff pressure matched the top blood pressure.
Why it mattered. Blood pressure could now be measured safely on anyone, without cutting an artery.
Riva-Rocci wrapped an inflatable cuff around the upper arm, pumped it up with a rubber bulb, and read the pressure on a column of mercury. When the pulse at the wrist vanished, the cuff pressure matched the top blood pressure.
Why it mattered. Blood pressure could now be measured quickly and safely on anyone, without cutting an artery.
Riva-Rocci wrapped an inflatable cuff around the upper arm, pumped it up and read the pressure on a mercury column. When the cuff pressed harder than the heart's push, the pulse at the wrist vanished. He built it from simple parts, including bicycle inner tube, and refused to patent it.
Why it mattered. Measuring blood pressure became quick, cheap and routine for every doctor.
Hall-Edwards X-rayed the hand of a colleague and found a needle buried under the skin. It is often called the first use of X-rays in clinical conditions. A month later he took an X-ray to guide a surgeon during an operation.
Why it mattered. Just two months after the discovery, X-rays were already helping doctors find what they could not see.
Gilman and Edwin FrostDartmouth College, Hanover, USA
Eddie McCarthy broke his wrist skating on the frozen Connecticut River. The Frost brothers, a doctor and an astronomer, X-rayed it in a college physics lab. It is recorded as the first clinical X-ray made in America.
Why it mattered. It showed a broken bone clearly enough to guide treatment, the job X-rays still do most often.
Thomas Edison's laboratoryWest Orange, New Jersey, USA
Edison's team tested thousands of chemicals and found that calcium tungstate glowed brightly when X-rays hit it. They built a fluoroscope: a box with a glowing screen you looked into to see bones move. Screens like this later helped expose X-ray film too.
Why it mattered. Turning invisible X-rays into visible light is still how many detectors work today.
Sircar, a doctor who founded the Indian Association for the Cultivation of Science, ordered an X-ray tube from Europe. His diary says his first try on 20 June was overexposed, but on 23 June he took good pictures of a frog and a coin. On 3 July he explained the new rays to an audience of more than 300 people.
Why it mattered. X-rays reached India within eight months of their discovery, the start of X-ray research in the country.
Arrhenius did long calculations by hand about how carbon dioxide in the air traps heat radiated by the Earth. He worked out that changing the amount of the gas could raise or lower Earth's temperature by several degrees. He was trying to explain the ice ages.
Why it mattered. It was the first attempt to put numbers on how much carbon dioxide warms the planet.
Westinghouse, using Tesla's AC systemNiagara Falls to Buffalo, New York, USA
The Adams hydroelectric plant at Niagara Falls started making AC power in August 1895. On 16 November 1896, power was sent more than 20 miles to the city of Buffalo. It was the first long-distance transmission of hydroelectric power in the United States.
Why it mattered. It settled the war of the currents: the grid would be AC, so a battery's DC must be inverted to use it.
Riva-Rocci wrapped an inflatable band round the upper arm and read its pressure on a mercury column. The cuff's pressure passes through the arm to the artery; when the pulse at the wrist vanished, the cuff matched the peak pressure.
Why it mattered. It made measuring blood pressure safe and simple, without cutting into an artery.
In an interview with the journalist Nellie Bly, the suffragist Susan B. Anthony said she thought the bicycle had done more to emancipate women than anything else in the world. Bicycles gave women independent travel and helped change clothing and ideas about what women could do.
Why it mattered. The bicycle was a social machine as much as a mechanical one.
During the plague epidemic in Bombay, Haffkine made a vaccine from killed plague bacteria and tested it first on himself. Earlier, in 1893–94, he had vaccinated thousands of people against cholera in Calcutta and villages of Bengal and Assam. His Bombay laboratory is today’s Haffkine Institute.
Why it mattered. India became one of the first places where vaccines were tried at large scale and their results counted.
Working in an army hospital in Secunderabad, Ross found malaria parasites in the stomach of an Anopheles mosquito that had fed on a patient. He later worked out the whole cycle in birds. He won the Nobel Prize in 1902.
Why it mattered. Knowing the mosquito spreads malaria made nets, drainage and insect control part of medicine.
Felix Hoffmann at Bayer (credit disputed with Arthur Eichengrün)Elberfeld
For centuries people chewed willow bark for pain and fever. Its active part, salicin, becomes salicylic acid, which upsets the stomach. At Bayer, Felix Hoffmann made a gentler form, acetylsalicylic acid, sold from 1899 as aspirin.
Why it mattered. It showed how a plant remedy can be purified, tested and improved into a medicine.
Kent published a huge index of symptoms, each listing remedies graded by type. It became the most used repertory in classical homeopathy, including in India.
Why it mattered. It is still the model for how homeopaths look up a remedy, now often in software.
Haffkine tested his cholera vaccine on thousands of people in India from 1893. When plague struck Bombay in 1896, he made a plague vaccine in a makeshift lab and tried it on himself first, in January 1897. His Bombay lab later became the Haffkine Institute.
Why it mattered. It is often called the first vaccine developed in India.
Writing for a physiology textbook, Sherrington needed a word for the place where one neuron hands its message to the next. He chose synapse, from Greek for “to clasp”, suggested by a classics scholar.
Why it mattered. The gap he named turned out to be where most of the nervous system’s work is done.
Sherrington introduced the word synapse, from Greek for “to clasp”, for the junction where one neuron passes a signal to the next. He went on to show how nerve signals add up and hold each other back.
Why it mattered. It named the place where almost all brain computing happens.
Thomson showed that cathode rays are streams of tiny negatively charged particles, far lighter than atoms. They were soon called electrons: the charges that actually move in a wire.
Why it mattered. A century after Franklin, the thing that flows in a current was finally identified.
The Sidrapong hydel station, with two 65 kW generators driven by mountain streams, began supplying Darjeeling. It is the oldest hydroelectric station in India and is still preserved.
Why it mattered. One of the first public electricity supplies in Asia.
Studying how magnets change the light from atoms, the Irish physicist Joseph Larmor showed that charges circling in a magnetic field precess: they wobble round the field at a rate set by its strength.
Why it mattered. That wobble, now called Larmor precession, is the frequency every MRI scanner tunes its radio to.
Father Eugène Lafont and Pradyot Kumar TagoreCalcutta (today Kolkata), India
Lafont, a Jesuit science teacher at St. Xavier's College, had brought a Crookes tube to Calcutta years earlier. With the photographer Pradyot Kumar Tagore he made an X-ray of the ringed right hand of Lord Elgin, the Viceroy. It was published by the Photographic Society of India in 1897.
Why it mattered. It showed that people in India were not just reading about X-rays but making skilled pictures with them.
Karl Ferdinand BraunStrasbourg, then Germany (now France)
Braun built a glass tube that fired a beam of electrons at a screen coated with a glowing chemical. Magnets could steer the beam, so a spot of light moved wherever you wanted. In Japan and Korea the CRT is still sometimes called the “Braun tube”.
Why it mattered. The CRT became the screen inside almost every television for the next hundred years.
Chicago's Palmer House hotel is said to have been one of her first customers, in 1887. Her company was renamed Cochran's Crescent Washing Machine Company in 1897 and opened its own factory the next year, with Butters as manager. Big models could wash and dry hundreds of dishes in a few minutes, but most homes had no supply of hot water to run one.
Why it mattered. For decades, dishwashers were machines for hotels, restaurants and hospitals, not families.
Bose built his own senders and detectors of very short radio waves, now called millimetre waves. With prisms, lenses and wire grids he showed they reflect, refract and totally reflect just like light. In 1897 the Royal Society published his tests of total reflection between two prisms with a thin air gap.
Why it mattered. It showed that Snell's law holds for invisible electromagnetic waves too, and made Bose a pioneer of microwave research.
J. Stuart Blackton and Albert E. Smith (attributed)New York, USA
Albert E. Smith later wrote that he and Blackton animated his daughter's jointed wooden circus toys, moving them a little between exposures. The film is lost. Smith dated it to about 1897 or 1898, but a film of that name was reviewed in 1908, so historians are not sure when it was made.
Why it mattered. It is often named as the first stop-motion film, though the date is uncertain.
Months after X-rays were discovered, the medical student Cannon fed animals food mixed with bismuth salts, which show up on X-ray film. He watched waves of squeezing push food along, and saw that fear could stop them.
Why it mattered. It was the first time people could watch peristalsis inside a living body.
The Polish pathologist Browicz saw cells lining the liver's blood channels that had swallowed red blood cells and other material. He recognised them as macrophages, cells that eat germs and debris. Kupffer revised his own view the same year. Today they are called Kupffer cells, or sometimes Browicz-Kupffer cells.
Why it mattered. These cells catch almost all the gut bacteria that reach the liver before they can spread.
Walter B. CannonHarvard Medical School, Boston, USA
Only months after X-rays were discovered, Cannon, a first-year medical student, fed animals food mixed with bismuth, which shows up on X-rays. He could watch waves of squeezing push food along the gut, and see that fear or distress could stop them. He summed up his work in The Mechanical Factors of Digestion in 1911.
Why it mattered. It was the first time people could watch peristalsis happening inside a living body.
Soon after X-rays were discovered, the medical student Walter Cannon fed animals food mixed with bismuth salts, which show up on X-ray, and watched waves of squeezing sweep across their stomachs. His first paper appeared in the first issue of the American Journal of Physiology.
Why it mattered. It revealed peristalsis and the stomach’s mixing, and led to the barium meal X-ray.
Jagadish Chandra BosePresidency College, Calcutta, India
Bose built his own X-ray apparatus and boosted it with a Tesla transformer. In a letter from about February 1898 he wrote of examining a patient with a broken back, the first recorded medical use of X-rays in India. A newspaper in May 1898 described his X-ray of a human palm showing only bones.
Why it mattered. An Indian scientist had designed, built and improved his own machine within about two years of the discovery.
Edwin Votey, Aeolian CompanyDetroit and New York, USA
Votey finished the first Pianola in his Detroit workshop in 1895. It read a punched paper roll and used air pressure to press the keys. The Aeolian Company put it on sale in the autumn of 1898. From 1904 the German Welte-Mignon went further, replaying a real pianist's speed, loudness and pedalling.
Why it mattered. Anyone could now fill their home with piano music, even if they could not play.
A freewheel lets the rear wheel keep turning while the pedals stay still, so riders can coast. Coaster brakes, worked by pedalling backwards, followed.
Why it mattered. You no longer had to pedal every second the wheels turned.
Bhatavdekar, a Bombay photographer, bought a film camera from London and filmed a wrestling match. He is widely considered the first Indian to make a motion picture.
Why it mattered. Indians were filming their own country within four years of cinema's birth.
William Bayliss and Ernest StarlingUniversity College London
In dogs, Bayliss and Starling showed that squeezing the intestine at one point makes the gut above it contract and the gut below it relax. This happens even when the nerves from the brain are cut.
Why it mattered. It explained how peristalsis always pushes food the right way.
William Bayliss and Ernest StarlingUniversity College London, England
Bayliss and Starling found that when something stretches the intestine, the muscle just behind it squeezes and the muscle just ahead of it relaxes. This pushes the contents forward. They called it the law of the intestine, and it works even when the gut's links to the brain are cut.
Why it mattered. It explained the reflex behind peristalsis and showed the gut has its own nervous system.
Fleischman studied the new science herself and opened an X-ray lab in San Francisco by 1897. She X-rayed soldiers wounded in the Spanish-American War, including one with a bullet lodged in his brain. Years of unshielded work gave her cancer, and she died in 1905.
Why it mattered. She was a pioneer of battlefield X-rays and one of the first women to die from radiation.
The Belgian driver Camille Jenatzy built a bullet-shaped electric car called La Jamais Contente, ‘The Never Satisfied’. Two electric motors pushed it to about 105.9 km/h. Sources disagree on whether the record run was on 29 April or 1 May.
Why it mattered. It was the first road vehicle to go faster than 100 km/h, proof that electric cars were once the speed kings.
In Grandma's Reading Glass, a boy looks through a magnifying glass, and Smith cuts to big circular close-ups of what he sees: a watch, a canary, his grandmother's eye.
Why it mattered. It is one of the earliest films to cut between a wide shot and close-ups from a character's point of view.
At the 1900 Paris Exposition the Phono-Cinéma-Théâtre showed short films of famous actors and singers with sound from phonograph cylinders played alongside. Keeping the two in step was hard, and the sound was too quiet for a big hall.
Why it mattered. It showed the dream of talking pictures and its two big problems: sync and loudness.
Ehrlich proposed that cells carry “side chains” that grab a toxin like a lock and key, and that cells release extra copies into the blood as antitoxins. He dreamed of “magic bullets”: medicines that hit only germs. He shared the 1908 Nobel Prize with Metchnikoff.
Why it mattered. His lock-and-key idea is how we still picture antibodies binding antigens.
The US Navy bought John Holland's Holland VI and commissioned it as USS Holland in October 1900. It flooded ballast tanks to dive, used a petrol engine on the surface and electric motors underwater.
Why it mattered. Ballast tanks plus engines made the submarine a practical ship.
Lebedev shone light on tiny metal vanes hung in a vacuum and measured the push, announcing it at the 1900 International Congress of Physics in Paris. Nichols and Hull in the USA confirmed it more precisely in 1901–03.
Why it mattered. The first measurement of light's momentum.
Women in South Indian homesTamil Nadu, Kerala and across South India
South Indian kitchens had two big stones. The flat ammikkal ground masala pastes, and the aattukkal, a heavy stone with a hollow and a round stone turned inside it, made idli and dosa batter from soaked rice and urad dal. Making batter meant soaking grains overnight and then grinding by hand for a long time, work that fell mostly on women.
Why it mattered. Slow stone grinding became the standard every electric grinder has been judged against.
Planck finally found the formula for how much of each colour a black body gives off at any temperature. To make it work he had to assume energy is given out in tiny fixed packets, which he called quanta. He won the Nobel Prize in Physics for 1918.
Why it mattered. His law explains the colour of a red hot coil and the infrared glow of your skin, and it began quantum physics.
Around 1900, electric cars made up about a third of the vehicles on American roads. They were quiet, clean and easy to start, with no crank and no gear changes. But their batteries were heavy and ran out quickly, so they suited short trips in town.
Why it mattered. Cheap petrol, better roads and the electric starter soon pushed electric cars aside for almost a century.
Torakusu Yamaha started out making reed organs in Hamamatsu in 1887. In 1900 his company built an upright, the first piano made in Japan, and its first grand followed in 1902.
Why it mattered. It began a Japanese piano industry that would one day lead the world.
Drude pictured a metal as a gas of free electrons that bump into the atoms. An electric field gives them a slow drift on top of their random motion, and the drift speed grows in proportion to the field. That gives J = σE, Ohm's law for a piece of material.
Why it mattered. Ohm's law stopped being just a rule and got a reason.
Fire! follows a fire from the street to a burning bedroom and back outside, across several shots. A firefighter carries a rescued person out of one shot and into the next.
Why it mattered. It showed how action can carry on across a cut, the seed of continuity editing.
The Japanese chemist Jokichi Takamine and his assistant Keizo Uenaka purified the active substance from adrenal glands and crystallised it. Takamine called it Adrenalin. It was soon used to stop bleeding and to treat asthma attacks.
Why it mattered. It was the first hormone ever to be purified.
Landsteiner mixed the blood of his colleagues and saw that some combinations clumped. He sorted people into groups now called A, B and O; AB was found a year later. In 1940 he and Alexander Wiener described the Rh factor.
Why it mattered. Matching blood groups made transfusion safe; he won the 1930 Nobel Prize.
Examining the pancreases of people who had died with diabetes, the American pathologist Eugene Opie found the islets damaged, even when the rest of the gland looked normal.
Why it mattered. It pointed the search for the missing substance at the islets, not the juice-making cells.
In a paper called "On the psychophysics of the sense of taste", Hänig dripped sweet, sour, salty and bitter solutions on spots around the edge of people's tongues and found the weakest strength each could notice. The differences between spots were small.
Why it mattered. His careful data were later misread as a tongue map, one of the most famous myths in science teaching.
In 1897 the Werner brothers sold a 'Motocyclette' with its engine in front of the handlebars, which made it hard to handle; the name became the French word for motorcycle. At the end of 1901 their 'New Werner' put the engine low in the frame, where a bicycle's pedals would be.
Why it mattered. Low and central is where a motorcycle's engine has sat ever since, still called 'the New Werner position' for years: it keeps the bike stable.
A bicycle and gun-parts maker in Redditch built its first motorcycle in 1901. The name Royal Enfield came from its work for the Royal Small Arms Factory.
Why it mattered. It is the oldest motorcycle brand still in production, and it later became an Indian company.
George Hendee and Oscar HedstromSpringfield, Massachusetts, USA
The Hendee Manufacturing Company, a bicycle maker, built its first motorcycle in 1901 and sold it under the brand name Indian. By the 1910s it was one of the biggest motorcycle makers in the world.
Why it mattered. It showed that motorcycles could be built in large numbers, like bicycles.
Röntgen won the very first Nobel Prize in Physics for discovering the rays. He never patented X-rays, because he felt they should benefit everyone. Biographers say the prize money went to his university in Würzburg.
Why it mattered. Refusing a patent let any company or hospital build X-ray machines, which spread them fast.
3rd General Conference on Weights and MeasuresParis, France
Engineers liked to measure force by weight: a kilogram-force was the pull of gravity on one kilogram. But gravity is slightly different from place to place. So the conference fixed a standard value, 9.80665 metres per second squared.
Why it mattered. It made the kilogram-force exact, and it separated mass, in kilograms, from weight, which is a force.
Carl Miele and Reinhard ZinkannHerzebrock, Germany
Miele began in 1899 making cream separators and butter churns. Its first washing machine was a wooden tub with a paddle inside, turned by hand with a lever, much like a big butter churn. By 1910 Miele was selling a washer with its own electric motor.
Why it mattered. Farm machines for stirring milk gave engineers a ready-made way to stir clothes.
Wilhelm Maybach, Paul Daimler and Emil JellinekStuttgart, Germany
The businessman Emil Jellinek ordered a new racing car from the Daimler company and asked for it to carry his daughter's name, Mercedes. Maybach's Mercedes 35 hp was long and low, with a light engine at the front and a honeycomb radiator. It won races at Nice week in March 1901.
Why it mattered. It is widely considered the first modern car, the layout that replaced the ‘horseless carriage’.
The Wright brothers found that published lift data were wrong, so they built a small wind tunnel and tested about 200 model wing shapes. Two years later, on 17 December 1903, their Flyer made the first controlled powered flight.
Why it mattered. Measured lift, not guesswork, made the first aeroplane possible.
A German migrant trained in Kneipp's methods bought the name from Scheel and used it for his American School of Naturopathy and his magazine. He is called the father of naturopathy in the United States.
Why it mattered. In America naturopathy later grew to include herbs, homeopathy and supplements, unlike India's drug-free nature cure.
P. S. Varier opened a small clinic and pharmacy that grew into one of India’s largest Ayurvedic hospitals and medicine makers. Across India, vaidyas founded colleges and associations to revive the system.
Why it mattered. Standard, factory-made medicines and colleges shaped modern Ayurveda.
Early films flickered badly, because the light went dark each time the film moved. The first three-bladed shutter is credited to Theodor Pätzold and went into production with Messter in 1902. It blinks the light three times for every frame, so the eye sees a fast, steady flicker it can no longer notice.
Why it mattered. Flashing each frame two or three times is still how film projectors trick the eye, at 48 or 72 flashes a second.
Georges Méliès, with hand-colouring studios in ParisParis, France
Méliès filmed A Trip to the Moon in black and white. Some prints were then coloured by hand, one tiny frame at a time, with fine brushes. A coloured print of the film was found in Spain in 1993 and restored.
Why it mattered. It shows that film makers wanted to control colour long before cameras could record it.
A Trip to the Moon sent a group of astronomers to the Moon in a shell fired from a giant cannon. Méliès used substitution splices, double exposures, painted sets, models and smoke to tell the story. Some prints were even coloured by hand, frame by frame.
Why it mattered. It is widely considered the first great special effects film, and its rocket-in-the-eye image is still famous.
A Trip to the Moon used painted scenery, costumes, stage machines and camera tricks to send explorers to the Moon. The shot of the capsule landing in the Moon's face became one of the most famous images in film history.
Why it mattered. It showed that effects could carry a whole story, not just a single surprise.
Méliès wrote, directed and helped design A Trip to the Moon. He sculpted prototypes for the moon creatures' heads and feet himself, and drew sketches for the film's poster. Historians think he also worked with a painter on the painted scenery.
Why it mattered. It showed that a film's look could be invented on paper and in the workshop before the camera rolled.
Méliès, a stage magician turned filmmaker, sold A Trip to the Moon as a grand spectacle in 30 tableaux, a numbered list of scenes. He wrote, designed and drew his films himself, planning every trick before filming. Historians count him among the first filmmakers to use pre-production drawings.
Why it mattered. Breaking a film into a list of scenes is still the first step of every screenplay.
The stage magician Méliès built a glass-walled studio and invented trick effects: stopping the camera to make things vanish, double exposures and painted sets. His 14-minute film sends astronomers to the Moon in a shell fired from a cannon.
Why it mattered. It showed that films could tell invented stories with special effects, not just record real life.
Trying to protect dogs against sea-anemone poison, Richet and Portier found that a second small dose, weeks later, caused a sudden, violent reaction. They called it anaphylaxis, “against protection”.
Why it mattered. It was the first clue that the immune system can overreact, the basis of allergy.
William Bayliss and Ernest StarlingUniversity College London, England
Bayliss and Starling put a little acid into a dog's small intestine after cutting its nerves. The pancreas still poured out juice. When they injected an extract of the intestine lining into the blood, the pancreas responded too: a chemical, which they named secretin, carried the message.
Why it mattered. It proved that the body sends chemical messages through the blood, not only through nerves.
William Bayliss and Ernest StarlingUniversity College London
Bayliss and Starling showed that when stomach acid reaches the duodenum, its lining releases a substance into the blood that makes the pancreas pour out juice. They called it secretin. In 1905 Starling coined the word hormone for chemical messengers like this.
Why it mattered. It showed that organs can talk to each other through the blood, and founded endocrinology.
William Bayliss and Ernest StarlingUniversity College London, England
Bayliss and Starling put acid into a dog's intestine after cutting its nerves, and the pancreas still poured out juice. A chemical from the gut lining, which they named secretin, was travelling in the blood. Starling later coined the word 'hormone'.
Why it mattered. It proved that organs talk to each other with chemical messages, the idea behind insulin too.
William Bayliss and Ernest StarlingUniversity College London, England
Bayliss and Starling showed that when acid from the stomach reaches the intestine, the gut lining releases a substance into the blood that makes the pancreas pour out its juice. They called it secretin. In 1905 Starling coined the word hormone for chemical messengers like this.
Why it mattered. Secretin is often called the first hormone, and it showed organs can talk to each other through the blood.
A Parsi theatre troupe; the twin brothers Nanji and MahanjiMysore, India
Parsi theatre companies used the harmonium to accompany songs on stage all over India. For the coronation of Krishnaraja Wadiyar IV in 1902, a troupe brought harmoniums to Mysore. Two harmonium players kept by the king were among the first to teach it in Carnatic music.
Why it mattered. Travelling theatre spread the harmonium faster than any school could.
Stribeck measured friction in bearings over a range of speeds and loads. Friction was high when starting, fell steeply as an oil film formed, then rose slowly. Adolf Martens had seen the same pattern in 1888.
Why it mattered. The curve shows why engines wear most at start-up.
Otto Schultze (after Josip Belušić's 1888 patent)Berlin, Germany
Croatian inventor Josip Belušić patented an electric speedometer in 1888. Otto Schultze patented the eddy-current speedometer in 1902: a spinning magnet drags an aluminium cup against a spring, turning the needle. Speedometers became standard on cars from about 1910.
Why it mattered. It put instantaneous speed in front of every driver.
Cooper Hewitt found that an electric arc in mercury vapour inside a glass bulb lets current flow only one way. His mercury-arc rectifier turned AC into DC without moving parts. It was used to charge batteries and run trams and trains, and later to send power under the sea.
Why it mattered. A rectifier is the charger half of every inverter: it turns mains AC into DC to fill the battery.
Mysore State, begun under Dewan K. Seshadri Iyer; engineers including A. J. de LotbinièreShivanasamudra, Kingdom of Mysore
Generators at the Shivanasamudra falls sent power 147 km to the Kolar Gold Fields, said to be the longest power line in the world at the time. From 1905 it also lit Bangalore.
Why it mattered. It is often called Asia's first large hydroelectric transmission scheme. Japan's smaller Keage plant in Kyoto had started in 1891.
A Brooklyn printing company had a problem: in humid summers the paper swelled and the colours printed out of line. Carrier, a 25-year-old engineer, designed a system that blew air over cold coils, which cooled the air and made its water vapour condense out. It controlled temperature and humidity together.
Why it mattered. It is widely regarded as the first modern air conditioning system, and it was built to dry the air, not to cool people.
Martin Kutta and Nikolai ZhukovskyMunich and Moscow
Kutta and Zhukovsky (Joukowski) showed independently that a wing's lift equals air density × speed × the circulation of air around it. The flow must leave a wing's sharp back edge smoothly, and that fixes how much lift it makes.
Why it mattered. It is why the wing in chapter 4 can be calculated at all.
Edwin S. Porter, Edison Manufacturing CompanyNew Jersey, USA
Porter's 12-minute western tells its story in about 14 shots, cutting between the robbers, the train and the telegraph office. It was a huge hit in the new nickelodeon theatres.
Why it mattered. Cutting between places that are far apart helped audiences learn to follow a story told in separate shots.
Edwin S. PorterEdison studio, New York and New Jersey
The Great Train Robbery cut between different places, following the robbers and then the posse, and was a huge hit. Film-makers everywhere learned that the cut itself could build suspense.
Why it mattered. It helped turn editing into the language of cinema.
Einthoven built a string galvanometer: a very thin wire between strong magnets that moves when the heart's current flows through it. Its shadow was photographed as a clear wavy line, the electrocardiogram. He named its bumps P, Q, R, S and T, names still used today, and won the 1924 Nobel Prize.
Why it mattered. It gave doctors a picture of the heart's electrical rhythm, still one of medicine's most used tests.
A schoolteacher in Kaluga published 'Exploration of Outer Space by Means of Reaction Devices' in the journal Nauchnoe Obozrenie. Using momentum conservation for each bit of exhaust, he showed a rocket's final speed is exhaust speed × ln(full mass ÷ empty mass). The issue was confiscated by the police for an unrelated article.
Why it mattered. It showed that spaceflight was possible, and why rockets need stages.
Riding a streetcar in snowy New York, Mary Anderson watched the driver keep reaching out to clear the glass. She designed a hand-operated arm with a rubber blade that swept the windscreen from inside, and received US patent 743,801. She never earned money from it, and her patent ran out in 1920.
Why it mattered. Windscreen wipers became standard equipment, and she was inducted into the National Inventors Hall of Fame in 2011.
Wilbur and Orville WrightKitty Hawk, North Carolina, USA
The Wright brothers ran a bicycle shop in Dayton, Ohio. They used its tools, its chain drives and their understanding of balance and control to build the first successful powered aeroplane.
Why it mattered. Balancing a bike taught them that a pilot must actively control an aircraft, not just keep it steady.
Tsiolkovsky, a schoolteacher, used Newton's laws to work out how fast a rocket can go by throwing its fuel out of the back. He showed rockets could reach the speeds needed for spaceflight. A British mathematician, William Moore, had found the same formula back in 1810 to 1813.
Why it mattered. Every space launch is planned with his equation, which is Newton's third law put to work.
Peter Cooper Hewitt; Billy Bitzer (Biograph)Pittsburgh and New York
Cooper Hewitt patented his mercury-vapour lamp in 1901. Its long tubes gave a blue-green glow that suited the film of the day, which could not see red. Biograph's Westinghouse Works films of 1904 are probably the first films lit this way, and Biograph was using the lamps in its studio by about 1905.
Why it mattered. For the first time, film-makers could shoot indoors without waiting for the sun.
Pavlov showed that the sight, smell and taste of food start gastric juice flowing, through nerves including the vagus nerve. He won the Nobel Prize for his work on the physiology of digestion, years before his famous work on conditioned reflexes.
Why it mattered. It showed that the brain switches digestion on before food even arrives.
Christian Bohr, Karl Albert Hasselbalch and August KroghCopenhagen, Denmark
The team measured how much oxygen blood holds at different pressures. The curve was S-shaped, and more carbon dioxide made blood hold oxygen less tightly. This is the Bohr effect. A few years later August and Marie Krogh showed that oxygen simply diffuses from the air sacs into the blood.
Why it mattered. Busy muscles make carbon dioxide, so they get more oxygen exactly when they need it.
Pavlov studied dogs with small surgical pouches of stomach and showed that the sight, smell and taste of food start gastric juice flowing, through nerves including the vagus nerve. He won the Nobel Prize “in recognition of his work on the physiology of digestion”, years before his famous work on conditioned reflexes.
Why it mattered. It showed that the brain and nerves switch digestion on.
Christian Bohr, Karl Albert Hasselbalch and August KroghCopenhagen, Denmark
The team measured how much oxygen blood holds at different pressures. The curve was S-shaped, and more carbon dioxide made blood hold oxygen less tightly. This is the Bohr effect, and it relied on a precise instrument that Krogh designed.
Why it mattered. Busy muscles make carbon dioxide, so they get more oxygen exactly when they need it.
Anschütz-Kaempfe patented a gyrocompass: a fast-spinning rotor that the torque from Earth's rotation turns until it points true north. Elmer Sperry built a rival design in the United States soon after.
Why it mattered. Precession became a way to steer ships without a magnetic compass.
Dally helped Thomas Edison test X-ray tubes and often held his own hands in the beam. His skin was badly burned, cancer followed, and doctors removed both his arms before he died. Edison was so shaken that he stopped working with X-rays.
Why it mattered. His death is widely considered the first in America from X-ray work, and it pushed people to take radiation seriously.
At a mathematics congress Prandtl explained that friction matters only in a thin layer next to a surface. Outside it, Euler's and Bernoulli's frictionless rules work well; inside it, the flow can peel off, which causes stalls and drag.
Why it mattered. It showed when Bernoulli can be trusted and why it sometimes can't.
Strowger's colleagues at Automatic ElectricChicago
Engineers working with Strowger's company developed the rotary dial, which breaks the line current once for each step as a spring turns it back. By about 1907 the familiar finger-wheel dial with a finger stop had arrived.
Why it mattered. The rotary dial made the caller the operator, one pulse at a time.
Early cinemas switched to carbon arc lamps: a blazing spark between two carbon rods. They were the only light bright enough for a large screen. The rods burned away, so projectionists had to keep adjusting the gap and change the rods often.
Why it mattered. A brighter lamp meant bigger screens and bigger audiences, and carbon arcs lit cinemas until the late 1960s.
Painting every frame by hand was slow. Pathé's workers traced parts of each frame, and a machine cut a stencil for each colour. Rollers soaked in dye then coloured many prints quickly, up to about six colours per film. It was called Pathécolor, later Pathéchrome.
Why it mattered. It was the first factory system for deciding what colour each part of a picture should be.
Nettie StevensBryn Mawr College, Pennsylvania, USA
Studying mealworm beetles, Nettie Stevens found that females had pairs of large chromosomes, while males had one large and one small one. She concluded that the sperm's chromosome decides whether the young is female or male. Edmund Wilson reached a similar conclusion the same year.
Why it mattered. It explained why the sperm, carrying an X or a Y, sets a baby's sex.
Ernest StarlingRoyal College of Physicians, London, England
In his Croonian Lectures, Starling needed a name for these chemical messengers. He used hormone, from a Greek word meaning to arouse or set in motion. The idea came from a dinner-table chat with colleagues in Cambridge.
Why it mattered. A single word gave a whole new science something to talk about.
Edkins found that an extract of the lower stomach, injected into the blood, made the stomach produce acid. He called the messenger gastrin. Many doubted it until gastrin was purified in 1964.
Why it mattered. It added the stomach’s own acid switch to the list of gut hormones.
John Scott Haldane and John Gillies PriestleyOxford, England
Haldane and Priestley measured the air at the very end of a breath, which comes from deep in the lungs. Whatever they did, the level of carbon dioxide there stayed almost the same, and even a small rise made people breathe much harder. They showed that the brain controls breathing mainly by watching carbon dioxide, not oxygen.
Why it mattered. It is why holding your breath gets hard so fast: carbon dioxide builds up long before oxygen runs low.
Korotkoff, a young army surgeon, put a stethoscope below a pressure cuff and let the air out slowly. Tapping sounds started and then stopped, marking the top and bottom blood pressure. His report was less than a page long.
Why it mattered. The 120 over 80 you get at a clinic still comes from his method.
Nikolai KorotkoffImperial Military Medical Academy, St Petersburg, Russia
Korotkoff, a young army surgeon, put a stethoscope below a pressure cuff and let the air out slowly. He heard tapping sounds start and then stop, and showed they mark the top and bottom blood pressure. His report was less than a page long.
Why it mattered. The two numbers you get at a clinic, like 120 over 80, still come from his method.
Korotkoff, a young army surgeon, put a stethoscope below the cuff and let the pressure out slowly. Tapping sounds start when blood first squeezes through and stop when the artery is fully open. His report was less than a page long.
Why it mattered. It gave us the two numbers, like 120 over 80, that doctors still write down.
Electric motors of the time were big and heavy. Beach invented a small, high-speed ‘fractional horsepower’ motor that could run on the electricity coming into homes. Hamilton Beach called it a ‘universal’ motor: its magnet coils and spinning coils are wired in a chain, so it runs on AC or DC, starts with a strong twist and spins very fast.
Why it mattered. Most mixer grinders still use a universal motor, which can spin at around 20,000 turns a minute.
In 'On the Electrodynamics of Moving Bodies' Einstein showed that the speed of light is the same for every observer. Velocities then combine as (u + v) ÷ (1 + uv/c²), so nothing with mass can reach c.
Why it mattered. Simple adding of velocities is only an everyday approximation.
Pollen specks in water jiggle for ever, which Robert Brown had seen in 1827. Einstein showed this Brownian motion is caused by water molecules knocking the specks about, and that the distance they wander grows as the square root of time. He linked it to the diffusion coefficient D.
Why it mattered. It explained diffusion from the bottom up, as random molecular kicks, and gave a way to count molecules.
In a short paper, Einstein showed that anything that gives out energy E loses mass E ÷ c². For burning, the loss is about one part in ten billion, far too small to weigh.
Why it mattered. It is the one tiny exception to Lavoisier's law, and it matters only in nuclear reactions.
Korotkov, a military surgeon, listened with a stethoscope below the cuff while letting it down. Taps start at the systolic pressure and stop at the diastolic. His report was only 281 words long.
Why it mattered. It is still how doctors take blood pressure by hand.
In a three-page paper, Einstein showed that when a body gives out energy as light, its mass goes down by that energy divided by the speed of light squared. We now write this as E = mc². Mass and energy turned out to be two faces of one conserved quantity.
Why it mattered. It explained where the Sun's energy and nuclear energy come from, without breaking the conservation law.
As electricity arrived, electric ceiling fans largely took the place of rope-pulled punkahs in barracks and other big buildings. The old name lived on: in aircraft, the little air vent above your seat is still called a punkah louvre.
Why it mattered. A motor did the job that thousands of workers had done by hand.
While working at the patent office, Einstein published special relativity. Near the speed of light, Newton's laws give the wrong answers: an object's momentum grows without limit, so it can never reach light speed.
Why it mattered. It showed Newton's laws are a superb approximation for everyday speeds, not the final word.
Physicist Arthur Korn used a selenium cell to scan a photograph and sent a picture of the German Crown Prince over about 1,800 km of wire. His telephotography networks soon linked newspapers in Berlin, Paris and London.
Why it mattered. News photos could now travel faster than trains, and newspapers started to use them.
In “The Integrative Action of the Nervous System” Sherrington showed how reflexes combine, including how one muscle is told to relax while its partner contracts. He shared a Nobel Prize in 1932 with Edgar Adrian, who recorded single nerve fibres firing.
Why it mattered. It explained how simple circuits build smooth movement.
Carnot and his colleague Deflandre reported that blood from anaemic rabbits made other rabbits produce more red blood cells, and proposed a hormone behind it. The idea was debated for decades before it was proved.
Why it mattered. It started the search for erythropoietin, which turned out to come mainly from the kidneys.
Camillo Golgi and Santiago Ramón y CajalStockholm, Sweden
Golgi and Cajal shared the Nobel Prize for their work on the structure of the nervous system. In their lectures they still disagreed: Golgi defended a continuous net, Cajal separate neurons. Cajal was right.
Why it mattered. It crowned the discovery of the neuron as the brain’s basic unit.
Thaddeus CahillHolyoke, Massachusetts and New York City, USA
Cahill patented a way to make music with electricity in 1897. His Telharmonium used spinning dynamos to make pure tones, then added them together to build richer sounds. In 1906 the machine, weighing about 200 tons, opened in Telharmonic Hall in New York and sent music down telephone lines to hotels and restaurants.
Why it mattered. It was the first big machine to build musical sounds from electricity, by adding simple tones together, an idea every synthesizer still uses.
Ragis (kirtan singers) of Darbar SahibAmritsar, Punjab, India
The harmonium is thought to have entered kirtan at the Golden Temple in the early 1900s, probably between 1905 and 1908. Over the next century it replaced most of the older string instruments in Sikh devotional singing. Today ragi groups sing there for about 20 hours a day.
Why it mattered. It became the sound of Sikh worship for millions of people.
Brunhes found volcanic rocks magnetised in the opposite direction to today's field. In 1929 Motonori Matuyama in Japan showed such reversed rocks come from a particular age. Together they revealed that the Earth's field flips; the last full reversal was about 780,000 years ago.
Why it mattered. It showed the Earth's magnet is not fixed, and later helped prove that the sea floor spreads.
Marsh patented nichrome, a mix of nickel and chromium. It resists electricity, so it gets very hot when a current flows, but it does not melt or crumble quickly in air.
Why it mattered. Nichrome-type wire inside a metal tube is the heating element in most electric geysers.
Gaston Dumond, Ernest Mathis, Maurice HoudailleFrance
French engineers patented hydraulic shock absorbers, which force oil through small holes. Houdaille's lever-arm design was widely used after the First World War.
Why it mattered. A spring alone keeps bouncing; a damper turns the bounce into heat. Every car and motorbike now pairs the two.
Stuart Cramer and Willis CarrierAsheville, North Carolina, and Buffalo, New York, USA
In a May 1906 speech to cotton mill owners, the engineer Stuart Cramer used the words ‘air conditioning’ for controlling the moisture and cleanliness of air in mills. That January, Carrier had been granted US patent 808,897 for an ‘Apparatus for Treating Air’.
Why it mattered. The idea got its name, and Carrier's company later took the name too.
Nernst studied chemical reactions at lower and lower temperatures. In 1906 he proposed his heat theorem: as things approach absolute zero, their entropy changes shrink towards nothing. By 1912 he argued it also means no process can ever reach absolute zero in a finite number of steps.
Why it mattered. It became the third law, and it won Nernst the 1920 Nobel Prize in Chemistry.
Élie Metchnikoff and Stamen GrigorovParis, France, and Geneva, Switzerland
The Bulgarian student Grigorov identified the bacterium that sours yoghurt. Metchnikoff, a Nobel prize-winning immunologist at the Pasteur Institute, argued that such friendly bacteria could keep the gut healthy.
Why it mattered. It was an early step towards seeing gut microbes as partners, not just germs.
Élie Metchnikoff and Stamen GrigorovParis, France and Geneva, Switzerland
In 1905 Stamen Grigorov, a young Bulgarian doctor in Geneva, found the rod-shaped bacterium that turns milk into yogurt. Metchnikoff, a Russian-born scientist at the Pasteur Institute, argued in his 1907 book The Prolongation of Life that such bacteria could crowd out harmful gut microbes. He won a Nobel Prize in 1908, for his separate work on immunity.
Why it mattered. It was the start of the idea that some gut bacteria are good for us.
Weiss proposed that inside iron a strong internal 'molecular field' lines up the atomic magnets in small regions, now called domains. An unmagnetised nail has its domains pointing every which way; a magnet nearby lines them up.
Why it mattered. It explained why iron can be magnetised and demagnetised, and why it stops at the Curie point.
Einstein realised that someone falling freely feels no weight at all. If inertial and gravitational mass are truly equal, gravity and acceleration cannot be told apart. He made this equivalence principle the starting point of general relativity, finished in 1915.
Why it mattered. A coincidence Newton had just accepted became the key to a new theory of gravity.
Rosing patented a system that used a mechanical scanner and a photocell to read the scene and a cathode-ray tube to show it. On 9 May 1911 he showed crude shapes on the tube. His student and helper was a young Vladimir Zworykin.
Why it mattered. It was one of the first times a CRT was used as a television screen.
Maytag was founded in 1893 by Frederick Maytag and partners to make farm machinery. In 1907 it built its first washer, the Pastime: a wooden tub worked by a hand crank. Washers soon became the company's main business.
Why it mattered. Washing machines went from a sideline to one of the biggest home products in America.
Hurley Machine Company and the 1900 Washer CompanyChicago, Illinois, and Binghamton, New York, USA
Electric washing machines were advertised in newspapers as early as 1904. The Hurley Machine Company of Chicago made its electric Thor washer from about 1907 and marketed it widely from 1908. The 1900 Washer Company of Binghamton was also making electric washers by 1906 or 1907, and nobody knows who put the very first motor on a washer.
Why it mattered. A small motor did the hours of cranking, and every washing machine since has had one.
In 1904 Diehl's company gave its fan a split-ball joint so you could point it in different directions. About three years later this grew into an oscillating fan that swung from side to side by itself.
Why it mattered. Oscillation spreads one fan's breeze across a whole room.
Fantasmagorie is a stream of shape-shifting stick figures, drawn in black on paper and shot on negative film so it looks like chalk on a blackboard. Cohl made about 700 drawings, each shot twice: animation on twos.
Why it mattered. Film historians call it the first fully hand-drawn animated cartoon.
The chemist Kikunae Ikeda wondered why kombu seaweed broth (dashi) tasted so savoury. He boiled down large amounts of kombu and extracted glutamic acid, whose salts gave the taste. He named it umami, from the Japanese for "delicious".
Why it mattered. It was the first scientific claim for a fifth basic taste, though the West took most of a century to accept it.
Jean Perrin tracked tiny beads through a microscope and measured their Brownian wandering. The numbers matched Einstein's theory and gave the number of molecules in a mole. He won the 1926 Nobel Prize in Physics.
Why it mattered. After Perrin, few scientists still doubted that atoms and molecules exist.
In a short letter to the journal Nature, a Scottish engineer suggested using two cathode-ray beams, one to read the picture and one to paint it. There would be no spinning parts at all. Nobody could build it yet.
Why it mattered. It is widely seen as the first description of fully electronic television.
John L. Leal and George W. FullerJersey City, New Jersey, USA
The doctor John Leal and the engineer George Fuller set up a plant that added chlorine to Jersey City's water at the Boonton Reservoir, every day, all the time. It treated about 40 million gallons a day. Within a few years chlorinated water spread across America and typhoid deaths fell.
Why it mattered. It was the first continuous chlorination of a US city's drinking water, one of the great public health wins in history.
Henry Ford and Ford Motor CompanyDetroit, Michigan, USA
Ford introduced the Model T, a simple, tough car that ordinary families could fix themselves. The touring car first cost $850. Ford kept making it cheaper, and more than 15 million were built by 1927.
Why it mattered. It turned the car from a toy for the rich into everyday transport for millions.
After years of building ever better coolers, Onnes turned helium gas into a liquid at about 4.2 kelvin. By pumping on the liquid he got down to about 1.5 kelvin, the coldest place on Earth at the time. Three years later his team found that mercury loses all electrical resistance when it is this cold.
Why it mattered. It opened the door to the science of the very cold, and won him the 1913 Nobel Prize in Physics.
Sheaffer patented a fountain pen with a lever on the side. Flip it and it squeezed a rubber ink sac inside; let go and the sac drew in fresh ink from a bottle.
Why it mattered. No more eyedroppers: filling a pen became clean and quick.
In The Lonely Villa, robbers break into a house while the father races home. Griffith cuts back and forth between them, faster and faster, until the rescue.
Why it mattered. Cross-cutting between two lines of action became one of the most powerful tools for suspense.
Film makers agreed on one standard: film 35 mm wide with four perforations along each edge for every frame. That gives 16 frames in every foot of film. Cameras, labs and projectors everywhere could now share the same film.
Why it mattered. The 4-perf 35 mm frame still sets the size of a 'Super 35' digital sensor today.
Ikeda patented a way to make monosodium glutamate (MSG) and teamed up with the businessman Saburosuke Suzuki to sell it as a seasoning called Ajinomoto, "essence of taste".
Why it mattered. It turned a taste discovery into one of the world's most widely used food ingredients.
Weather scientists needed a handy unit for air pressure, and Bjerknes is credited with the bar: 100,000 newtons per square metre, close to the air pressure at sea level. Weather maps were drawn in millibars for most of the twentieth century. Today forecasters use hectopascals, which are exactly the same size.
Why it mattered. It gave air pressure a round number, and it is why tyres are still pumped in bar.
Bailey split the solar heater in two: thin pipes on the roof to catch the sun, and an insulated tank that kept the water hot. Warm water rose on its own from the collector into the tank. His company sold more than 4,000 of these ‘Day and Night’ heaters by 1918.
Why it mattered. Hot water rising above cold is how solar heaters and storage geysers keep a hot layer ready at the top.
Around 365,000 pianos were sold in the United States in 1909, when the country had about 90 million people. Hundreds of piano firms were founded between 1880 and 1910. Then gramophones and radio pulled buyers away.
Why it mattered. Before radio and TV, the piano was the family's home entertainment.
Most silent films were not shown in plain black and white. Tinting dyed the whole frame one colour, such as blue for night or red for fire. Toning swapped the dark silver for a coloured chemical, so the shadows changed colour instead. By 1920, most films used one or both.
Why it mattered. It was the first colour grade: one mood colour for a whole scene.
Starewicz, a museum director and insect collector, wired the legs of dead stag beetles and moved them frame by frame to film them fighting. The short is called Lucanus Cervus.
Why it mattered. It is one of the earliest surviving puppet animations, made with real insects as puppets.
Christian Bohr thought lung cells actively pumped oxygen into the blood. August and Marie Krogh, testing on themselves with a single-breath method, showed that oxygen and carbon dioxide just drift across the thin wall from high pressure to low. Marie’s single-breath idea is still behind a lung test used today.
Why it mattered. It showed why the lungs need a huge, thin surface: diffusion alone has to do the job.
Govindrao Tembe, a largely self-taught harmonium player, composed the music for the play Manapman in 1910. Natya sangeet, the song-filled Marathi stage, used the harmonium as its main instrument, following pioneers like Bhaiyya Ganpatrao. Tembe later wrote music for the first Marathi talkie film in 1932.
Why it mattered. Theatre and then film songs made the harmonium part of everyday Indian music.
Fred Osius, Louis Hamilton and Chester BeachRacine, Wisconsin, USA
Fred Osius set up the Hamilton Beach Manufacturing Company, named after two of his workers. One of its first products was a milkshake mixer: Beach's fast motor spun a spindle with a small agitator dipped into a cup. It was sold to drugstore soda fountains, and the same kind of spindle mixer is still used today.
Why it mattered. It proved that a small, fast motor could whip food in seconds.
The Walker brothers sold hand-cranked dishwashers for $20 with a free trial. GE Appliances, whose Hotpoint business later took Walker over, says Walker made the first front-loading, single-rack dishwasher in 1913. By 1921 Walker was advertising an electric ‘Dishwasher and Dryer’ for new homes.
Why it mattered. Electric motors began to do the hard work that hands had done.
Alva Fisher, an engineer at the Hurley company, received US patent 966,677 for a washing machine driven by an electric motor. Many books say he invented the electric washer. Historians who checked the records point out that electric washers were already on sale before his patent, and that other patents came first.
Why it mattered. A patent is not always proof of who invented something first.
A few years after the mercury vapour lamp was invented, Marseille used ultraviolet lamps to disinfect city drinking water. It is widely cited as the first full-scale UV water treatment.
Why it mattered. It showed that light alone could make water safe, the same job the UV lamp does in a home purifier.
The Kliegl brothers, who made stage lights, brought out their first motion-picture lights in 1911: powerful carbon arcs soon called klieg lights. In 1912 Biograph swapped its mercury tubes for bright white-flame arcs. The arcs gave off so much ultraviolet light that actors suffered sore, swollen eyes, known as klieg eye.
Why it mattered. Carbon arcs were bright enough to fake daylight, and they ruled film sets for years.
J. S. Haldane, Mabel FitzGerald, C. G. Douglas, Yandell Henderson and E. C. SchneiderPikes Peak, Colorado, USA
Four men lived for five weeks in the summit house of Pikes Peak, about 4,300 metres up, and measured how their breathing and blood changed. Mabel FitzGerald travelled alone to Colorado mining towns and measured people who lived at different heights. Together they showed how the body slowly adjusts, or acclimatises, to thin air.
Why it mattered. It explained why climbers must go up slowly, breathing more and making more red blood cells as they climb.
Gullstrand won the Nobel Prize in Physiology or Medicine for his work on the dioptrics of the eye, how the cornea and lens bend light. His schematic eye is an ancestor of the model used in this box.
Why it mattered. It made the eye a precise optical system that could be calculated.
Ernest Clements and Krishnaji Ballal DevalLondon, England, and Baroda (Vadodara), India
Deval measured the notes of the singer Abdul Karim Khan and argued they matched the ancient Indian idea of 22 shrutis, or microtones. With Ernest Clements he designed a shruti harmonium tuned to pure ratios, which was patented in London in 1911. It was shown at the All India Music Conference in Baroda in 1916 but did not catch on.
Why it mattered. It was the first attempt to make the harmonium fit Indian tuning instead of banning it.
The first carnival motordrome, a steep wooden bowl, appeared at Coney Island in 1911; vertical-walled versions followed by about 1915. The show spread round the world, and in India it became the maut ka kuan of village melas.
Why it mattered. It is circular motion as a show: the wall's push lets friction hold the rider up.
Willis CarrierAmerican Society of Mechanical Engineers, New York, USA
Carrier presented his ‘Rational Psychrometric Formulae’, which link temperature, humidity and dew point. Engineers could now calculate how much cooling and drying a building needed, instead of guessing.
Why it mattered. It turned air conditioning from trial and error into engineering.
Heike Kamerlingh Onnes, with Gilles Holst and othersLeiden
Having liquefied helium, Onnes's lab cooled solid mercury and measured its resistance. At about 4.2 K it abruptly dropped to zero. He won the 1913 Nobel Prize for his low-temperature work.
Why it mattered. Superconductors break Ohm's law completely: current flows with no voltage at all.
In this 12-minute comedy, insect puppets act out a story of jealousy, complete with a cinema inside the film. The puppets had jointed bodies so they could hold poses.
Why it mattered. It showed that puppets could act and tell a story, not just move.
Wooden cameras swelled, cracked and let in light. The Bell & Howell 2709 had a body of cast aluminium, pins that held each frame perfectly still, and a turret of four lenses you could swing into place. Hollywood studios soon relied on it.
Why it mattered. Steady pins and quick lens changes made pictures sharper and filming faster.
The psychologist Wertheimer flashed two lights one after the other. With the right gap between them, people saw pure movement, which he called the phi phenomenon. It helped show that film motion is made by the brain, not by images lingering in the eye.
Why it mattered. It explains why 24 still frames a second look like motion, and why 'persistence of vision' is a myth.
The pharmacist Wilbur Scoville, working for the drug company Parke-Davis, soaked dried chillies in alcohol, then diluted the extract with sugar water until a panel of tasters could no longer feel the heat. The number of dilutions became the Scoville heat unit.
Why it mattered. It gave the world a scale for chilli heat, still used today, though labs now measure capsaicin with machines.
Tagore had played the harmonium in his youth, as his own memoirs describe. Later he wrote the famous line calling it that bane of Indian music, and said he practised with a tanpura so as not to be a slave to the keyboard. The harmonium was kept out of his school at Santiniketan for a long time.
Why it mattered. His words made the harmonium a symbol in the fight over what Indian music should sound like.
Max von Laue, Walter Friedrich and Paul KnippingMunich, Germany
Laue guessed that the neat rows of atoms in a crystal might scatter X-rays the way fine lines scatter light. Friedrich and Knipping shone X-rays through a crystal and found a pattern of spots on film. Laue won the 1914 Nobel Prize in Physics.
Why it mattered. It proved X-rays are waves, like light but far shorter, and gave scientists a way to peer at atoms.
Maillard, a French doctor and chemist, heated sugars with amino acids, the building blocks of proteins, and watched them turn brown. His short note to the French Academy of Sciences described the reaction now named after him. It runs fast at about 140 to 165 °C and makes hundreds of new flavours.
Why it mattered. The Maillard reaction is what makes air-fried chips golden and tasty, and it needs dry heat, not oil.
Snelling, a chemist, found that propane and similar gases in petrol turn to liquid under modest pressure. On 17 May 1912 a customer named John Gahring began using this liquefied petroleum gas for lighting and cooking at home. Snelling's patent was granted in 1913, and he sold it to Frank Phillips for $50,000.
Why it mattered. LPG can be carried in a steel cylinder to homes far from any gas pipe, which is how most Indian kitchens get their flame.
Starting an engine used to mean turning a heavy crank by hand, and a kickback could break an arm. Kettering's company Delco built an electric system that started the engine, made the spark and powered the lights. Cadillac ordered 12,000 for its 1912 cars.
Why it mattered. Anyone could now start a petrol car with the press of a button, which removed a big advantage of electric cars.
M. K. GandhiPhoenix Settlement and Tolstoy Farm, near Durban and Johannesburg
In South Africa Gandhi read Kuhne and Just and tried hip baths, mud packs and diet changes on himself, his family and friends. He wrote a series of health articles in his paper Indian Opinion, later printed as 'A Guide to Health'.
Why it mattered. It began Gandhi's lifelong advocacy of nature cure.
Markov went through the first 20,000 letters of Pushkin's poem Eugene Onegin, counting how often a vowel followed a vowel or a consonant. He showed that each letter's chance depends on the one before it.
Why it mattered. It was the first chain of probabilities built from real text: the seed of every language model.
Édouard Belin built a portable picture transmitter that scanned with a photocell and could send over ordinary telephone lines. Reporters could carry it to the story.
Why it mattered. Its principle became the basis of the wirephoto services of the next decades.
Dadasaheb Phalke's Raja Harishchandra had a private preview at the Olympia Theatre on 21 April 1913, then opened to the public at the Coronation Cinematograph on 3 May. It ran four shows a day and was so popular its run was extended. Soon it was touring other cities on travelling projectors.
Why it mattered. It proved that Indian stories on an Indian screen could fill a hall, and Phalke is called the father of Indian cinema.
Phalke learned filmmaking on a trip to London, bought a Williamson camera and Kodak film, and made Raja Harishchandra, a silent film about a truthful king. It premiered at the Olympia Theatre in April and opened to the public in May 1913. No woman would act in it, so the queen was played by a man, Anna Salunke.
Why it mattered. It launched what became the biggest film industry in the world by number of films made.
At a time when many films were made up on set, the producer Thomas Ince insisted that each story be written out first, scene by scene and shot by shot. His continuity scripts let him plan budgets and keep several film crews working at once. In 1913 alone his studio released well over a hundred films.
Why it mattered. It turned the script into a working plan that tells everyone which shot comes next.
Phalke learned film-making in London, then wrote, directed, shot and edited a feature based on a story from Indian epics. Women did not act on screen then, so the queen was played by a man, Anna Salunke. Shree Pundalik (1912) came earlier, but is often left out as a filmed stage play.
Why it mattered. It is widely called India's first full-length feature film, and India's top film honour is named after Phalke.
In the novel Swann’s Way, the narrator dips a small cake, a madeleine, into tea. Its taste and smell bring back a flood of childhood memories he had forgotten. Scientists now call smell-triggered memories the “Proust effect”.
Why it mattered. It gave a name to something everyone has felt: smells unlock memories.
William Henry Bragg and William Lawrence BraggLeeds and Cambridge, England
The Braggs worked out a simple rule for how X-rays bounce off layers of atoms, and built an instrument to measure it. They used it to find where the atoms sit in crystals like salt. They shared the 1915 Nobel Prize in Physics, when Lawrence was just 25.
Why it mattered. X-ray crystallography became one of the most powerful tools in chemistry, biology and materials science.
William CoolidgeGeneral Electric, Schenectady, USA
Early gas tubes were moody and gave different X-rays every time. Coolidge used a very good vacuum and a heated tungsten wire that boiled off electrons on demand. Now the operator could set exactly how strong and how penetrating the X-rays would be.
Why it mattered. Almost every X-ray tube made since works this way.
X-rays that bounce around inside the body reach the film from odd angles and blur the picture like fog. Bucky put a grid of thin lead strips in front of the film to block these stray rays. In 1920 the American radiologist Hollis Potter made the grid move during the shot so its lines vanished.
Why it mattered. Grids made X-rays of thick body parts like the chest and belly much sharper.
Wolf's DOMELRE, short for DOMestic ELectric REfrigerator, sat on top of an ordinary icebox and replaced the block of ice with an electric cooling unit. It cost $900, about a year's pay, and several hundred were sold.
Why it mattered. For the first time, a home could make its own cold with no iceman calling.
At its Highland Park plant, Ford started moving each car past the workers instead of the workers walking to the car, first with ropes and then with a chain. Building a Model T fell from about 12 hours to about an hour and a half. The price kept dropping as output soared.
Why it mattered. Mass production changed not just cars but how almost everything is made.
KDK, founded in 1909, began mass-producing its “Typhoon” electric fan in 1913, among the first electric fans mass-produced in Japan. In 1917 it applied to protect a new spiral fan guard, and in 1921 it launched Japan's first ceiling fan.
Why it mattered. Fan making spread beyond the US and Europe, and guards made spinning blades safer to live with.
McCay drew a friendly dinosaur who seemed to obey his commands on stage. He drew the main poses first and the in-betweens after, reused cycles of drawings, and put registration marks on the paper. The film claimed 10,000 drawings, a number historians doubt.
Why it mattered. It gave a cartoon a personality, and its “split system” is the key-and-in-between method still used today.
Barré punched holes in the bottom of every sheet and slid them over pegs fixed to the animation table, so each drawing sat exactly over the last. His studio was one of the first set up only to make cartoons.
Why it mattered. Peg bars are still on every animation desk, and digital programs copy them.
Hurd patented drawing only the moving parts on clear sheets laid over one background painted on card. Early cels were made of cellulose nitrate, later acetate. Ink went on the front and paint on the back.
Why it mattered. Cels meant the background was painted once, not in every drawing. They ruled animation for 75 years.
Edward KendallMayo Clinic, Rochester, Minnesota, USA
Edward Kendall had spent months boiling down pig thyroid glands. On Christmas Day he finally saw crystals of the pure hormone, later called thyroxine. It was packed with iodine.
Why it mattered. It explained why iodine and seaweed help the thyroid, and led to thyroid tablets.
In the First World War, Marie Curie fitted cars with X-ray machines so surgeons near the fighting could find bullets and broken bones. She learned to drive, and trained about 150 women to work the machines. About 20 mobile units, nicknamed petites Curies, and some 200 fixed X-ray rooms helped examine an estimated million or more wounded soldiers.
Why it mattered. It brought X-rays of broken bones to where they were needed most.
Albert Hustin, Luis Agote and Richard LewisohnBrussels, Buenos Aires and New York
Working separately, three doctors added sodium citrate to donated blood so it would not clot. Hustin gave the first such transfusion in Brussels in March 1914, Agote in Buenos Aires that November, and Lewisohn worked out a safe dose in New York in 1915.
Why it mattered. Donor and patient no longer had to lie side by side: blood could be stored.
In his book The Music of Hindostan, Fox Strangways called the harmonium a serious menace to Indian music. He said it was out of tune with itself and would spoil singers' ears. He also noted it had already reached the remotest parts of India.
Why it mattered. His book spread the idea that the harmonium's fixed notes did not belong in ragas.
When the First World War began, Marie Curie fitted cars with X-ray machines so surgeons near the front could find bullets and shrapnel. Soldiers called them petites Curies, little Curies. She trained 150 women to run X-ray units, and it is estimated that more than a million wounded soldiers were X-rayed during the war.
Why it mattered. It proved how many lives quick X-rays could save and trained a generation of radiographers.
Parpart, who also patented street-cleaning machines, was granted US patent 1,090,925 for a ‘refrigerator attachment’. Popular accounts often call it an early electric fridge, but the patent itself describes coils that carry cold water from the melting ice around the shelves. Her husband's name is on the patent too, common for women inventors then.
Why it mattered. Women were inventing in this field too, even when a man's name sat beside theirs.
By 1914 American ice plants made about 26 million tons of ice a year, more than the roughly 24 million tons cut from frozen lakes and rivers. At its peak, around 1880 to 1900, the natural ice trade had employed about 90,000 people and 25,000 horses.
Why it mattered. Machines had beaten winter, and the next step was to put the machine in every kitchen.
Alexander Graham Bell and Thomas WatsonNew York to San Francisco
Bell, in New York, spoke to his old assistant Watson in San Francisco, about 5,500 km away. Vacuum-tube amplifiers along the line kept the voice loud enough to hear.
Why it mattered. Amplifiers meant distance no longer killed the voice.
Fleischer projected film of a real person, one frame at a time, onto glass and traced it onto paper. Dave Fleischer, dressed as a clown, was the reference for Koko the Clown in Out of the Inkwell.
Why it mattered. Copying a real performer's movement into a drawn character is the goal of motion capture, done by hand.
Fleischer projected film of his brother Dave, dressed as a clown, one frame at a time and traced him. The result was Koko the Clown, who moved like a real person. He called the machine a rotoscope.
Why it mattered. Tracing shapes on every frame, now called roto, is still one of the biggest jobs in any effects studio.
Phalke, who made India's first feature film in 1913, made a short object-animation film of matchsticks, Agkadyanchi Mouj. He had earlier filmed a pea plant growing at one frame a day.
Why it mattered. It is counted as India's first stop-motion film.
O'Brien animated clay-covered models of a dinosaur and an ape-man in The Dinosaur and the Missing Link. It was a short comedy that started his career in animated creatures.
Why it mattered. It began the line of stop-motion monsters that led to King Kong.
Max Fleischer projected live-action film, frame by frame, onto glass and traced it. His brother Dave, in a clown suit, performed the moves that became Koko the Clown in the Out of the Inkwell series (from 1918).
Why it mattered. Tracing real movement gave cartoons lifelike motion. Studios still use video reference today.
On The Warrens of Virginia, DeMille borrowed spotlights from a Los Angeles opera house and lit only half of an actor's face, making shadows where they would fall in nature. The story goes that his partner Sam Goldwyn feared cinemas would pay half price, until DeMille called it Rembrandt lighting, after the Dutch painter. Goldwyn then said they would pay double.
Why it mattered. The name, attributed to DeMille, is still used for a key light that leaves a small triangle of light on the shadow side of the face.
Cannon described how fear and rage make the sympathetic nerves and adrenaline speed the heart, raise blood sugar and pause digestion, preparing the body to fight or run. He later coined the word homeostasis.
Why it mattered. It gave the automatic system a purpose everyone could understand.
Einstein presented the final equations of his general theory of relativity to the Prussian Academy of Sciences. Mass and energy curve spacetime, and things move along the straightest paths through it. The theory explained a small wobble in Mercury's orbit that Newton's law could not.
Why it mattered. It replaced Newton's force at a distance with the shape of spacetime, and predicted black holes and gravitational waves.
Paul Peter Ewald and Carl Wilhelm OseenMunich, Germany, and Uppsala, Sweden
Light does not really slow down by bumping into atoms. The passing wave makes the electrons in each atom wobble, and each wobbling electron sends out a little wave of its own, slightly delayed. Ewald and Oseen proved that these waves add up to cancel the original wave and build a new one that moves more slowly.
Why it mattered. It is the modern answer to why the refractive index exists at all.
Nusselt published a paper called The Fundamental Law of Heat Transfer. He showed how to describe heat carried by moving air or water using a few numbers without units, so tests on a small model could predict a big machine. One of these, the Nusselt number, compares convection with plain conduction.
Why it mattered. Engineers still use his numbers to design radiators, engine fins and cooling fans.
Intolerance cuts between four stories set in ancient Babylon, the time of Jesus, 16th-century France and modern America, building all four towards their climaxes together.
Why it mattered. It pushed cross-cutting further than anyone before and deeply influenced Soviet film-makers.
Hugh Owen Thomas; brought to war by Robert JonesLiverpool, England, and the Western Front
Thomas, a Welsh bone-setter's son, designed a simple metal splint that keeps a broken thigh bone stretched and still. His nephew Robert Jones made it standard in the British Army from 1916, with splint drills for medics. Deaths from open thigh-bone fractures fell from about 80 percent to under 20 percent by commonly quoted figures.
Why it mattered. Holding a broken femur still in the field turned a usually deadly wound into a survivable one.
C. F. Martin & Co. and Oliver Ditson Co.Nazareth, Pennsylvania, USA
Players wanted louder guitars, and by 1921 Martin was mostly making steel-string guitars. In 1916 Martin built a big, deep body for the Ditson company, named after a huge battleship. Martin sold it under its own name from 1931, with X-bracing, and it became its best seller.
Why it mattered. The big-bodied dreadnought became the shape most people picture when they think "acoustic guitar".
While serving in the German army in the First World War, Schwarzschild found an exact solution of Einstein's equations around a single round mass. It contains a special radius, 2GM ÷ c², now called the event horizon. He died a few months later.
Why it mattered. It was the mathematical seed of the black hole.
Augusta and Adeline Van BurenNew York to Los Angeles, USA
In 60 days the Van Buren sisters rode two 1,000 cc Indian motorcycles about 8,800 km (5,500 miles) across the United States, over dirt roads and mountain passes. They wanted to prove that women could serve as military dispatch riders, and to support women's right to vote.
Why it mattered. They showed that a motorcycle could take anyone almost anywhere, at a time when many people thought women shouldn't ride at all.
Phalke had learned magic tricks before he made India's first feature film in 1913. In Lanka Dahan, based on the Ramayana, he used trick photography to show gods and wonders. Audiences loved it, and it became one of his biggest hits.
Why it mattered. Indian cinema used effects to tell its epics from the very start, a hundred years before Baahubali.
El Apóstol was a 70-minute political satire made from cut-out figures, not drawings on paper. No copy survives: the last known print was lost in a fire.
Why it mattered. A feature-length cartoon came from Argentina two decades before Hollywood made one.
Swiss dermatologist Bruno Bloch added a chemical called DOPA to thin slices of skin. Some cells in the bottom layer turned dark, showing they held the enzyme that makes the pigment melanin. These pigment-making cells are now called melanocytes.
Why it mattered. It pinned down the cells that give skin its colour and its shield against UV light.
Forbes was granted a patent for an electric water heater. A resistance wire heated the water, and a mercury thermometer with a contact inside switched the power off at the temperature you chose, then on again as the water cooled.
Why it mattered. Heating with electricity instead of flames removed fumes and fire from the bathroom, and the automatic switch is today's geyser thermostat.
Armies of the First World WarEurope and the United States
In the First World War armies used motorcycles to carry messages, pull machine guns in sidecars and move quickly behind the front. Harley-Davidson and Indian supplied thousands to the US Army.
Why it mattered. War orders made motorcycle makers big, and taught them to build tough, simple machines.
Radon, a mathematician at the Technical University of Vienna, showed how a flat shape can be worked out exactly from all of its sums along straight lines, and gave the formula for doing it. Nobody had any use for it in medicine for another fifty years.
Why it mattered. This is the Radon transform: CT's projections are exactly these line sums, and reconstruction runs it backwards.
Loughead patented car brakes worked by fluid in pipes, so that the force reached each wheel equally. Duesenberg's Model A of 1921 became the first production car with hydraulic brakes on all four wheels.
Why it mattered. Today almost every car's brakes are hydraulic, and every one relies on Pascal's principle.
Williams patented a way to film actors against a plain black background and turn their outline into a moving mask, called a travelling matte. The mask let a lab print the actor over a different background. It became known as the Williams process.
Why it mattered. Every green screen shot today still starts with this idea: separate the actor from the background.
Conrad Bahr of the New York City Water Department said he made the first torque-limiting wrench in 1918, so water-main bolts would not be over-tightened. He and George Pfefferle patented a ratcheting torque wrench that signals the set torque in 1935.
Why it mattered. Bolts could be tightened to exactly the right torque, not by feel.
Emmy Noether proved that every symmetry of nature comes with a conserved quantity. Because the laws of physics are the same here as over there, momentum is conserved; because they are the same today as tomorrow, energy is.
Why it mattered. Conservation of momentum turned out to be a property of space itself.
Alfred Mellowes, Nathaniel Wales and othersFort Wayne and Detroit, USA
In 1916 Alfred Mellowes' Guardian Frigerator Company began building home fridges in Fort Wayne, Indiana. It was bought by William Durant, head of General Motors, renamed Frigidaire, and taken over by GM in 1919. In 1918 Kelvinator sold what is described as the first home fridge with an automatic control, and by 1923 it had about 80% of the US market.
Why it mattered. Big companies started making fridges like cars, in large numbers, for ordinary families.
Noether was helping David Hilbert and Felix Klein with Einstein's new theory of gravity. She proved a theorem showing that every smooth symmetry in the laws of physics comes with something conserved. Because the laws are the same today as tomorrow, energy is conserved. Klein presented her paper to the Göttingen science society.
Why it mattered. It explained, for the first time, why conservation of energy is true.
Kurt Huldschinsky, Edward Mellanby, Elmer McCollumBerlin, Germany; London, England; Baltimore, USA
Rickets makes children's bones soft and bent. In 1919 Huldschinsky cured it with ultraviolet lamps, and Mellanby cured it in dogs with cod liver oil. In 1922 McCollum showed the helpful thing in the oil was a new vitamin, and named it vitamin D.
Why it mattered. Bones need vitamin D, made in sunlit skin, to take in calcium and harden.
Kurt Huldschinsky; Alfred Hess and Lester UngerBerlin, Germany; New York, USA
In Berlin, Kurt Huldschinsky shone an ultraviolet lamp on children with rickets, a disease that leaves bones soft and bent. X-rays showed their bones healing, even in an arm that was never lit. In 1921 Alfred Hess and Lester Unger in New York cured rickets by putting children in sunlight on a hospital roof.
Why it mattered. It revealed that skin makes something the whole body needs, later named vitamin D, when sunlight falls on it.
Arthur Eddington, Frank Dyson and teamPríncipe and Sobral, Brazil
During a total solar eclipse, expeditions photographed stars near the darkened Sun. The stars appeared shifted by about the amount Einstein predicted, twice what a Newtonian estimate gave. The news made Einstein world-famous overnight.
Why it mattered. It was the first big test that general relativity passed.
Herbert Johnston and the Hobart Manufacturing CompanyOhio, USA
Johnston, a Hobart engineer, invented an electric stand mixer, and by 1915 his 20-gallon model was standard in big bakeries. In 1919 Hobart brought out a version for homes, the KitchenAid Food Preparer.
Why it mattered. Electric mixing moved from factories into family kitchens.
Lev Kuleshov, with actor Ivan MosjoukineMoscow, Russia
Kuleshov is said to have cut the same expressionless close-up next to shots of a bowl of soup, a girl in a coffin and a woman on a divan. As Pudovkin told it, viewers praised the actor's hunger, grief and desire. No footage survives.
Why it mattered. It suggested that meaning comes from how shots are joined, not only from what is in them. Modern studies find a real but modest effect.
Leon Theremin (Lev Termen)Petrograd (today St Petersburg), Russia
While researching electronic sensors, Theremin built an instrument you play by waving your hands in the air. One hand moves near an antenna to change the pitch, and the other moves near a loop to change the volume. The violinist Clara Rockmore later became its greatest player and proved it could perform serious classical music.
Why it mattered. It showed that an electronic oscillator could be a real, expressive musical voice.
Most drums ring with messy, unmusical overtones. Raman and Kumar wrote in the journal Nature that Indian drums like the tabla and mridangam are a remarkable exception. The loaded drumhead gives overtones in a neat harmonic series, just like a violin string.
Why it mattered. It was the first scientific explanation of why the black spot turns a drum into a tuned instrument, and Raman went on to win the 1930 Nobel Prize in Physics for separate work on light.
A shoe-fitting fluoroscope let customers look down and see the bones of their feet wiggling inside new shoes. About 10,000 were sold in the US, and they spread to Britain, Canada and beyond. Pennsylvania became the first state to ban them, in 1957, once the radiation risk was clear.
Why it mattered. It is a reminder that a new technology can become a toy before people understand its risks.
Most drums make overtones that are out of tune with each other. Raman and Kumar showed in Nature that Indian drums like the tabla and mridangam give harmonic overtones, in a musical series like a string's, thanks to the loaded black patch on the drumhead.
Why it mattered. It explained, with physics, a design Indian drum makers had perfected by ear over centuries.
The Madras government asked a committee led by Mohammad Usman to report on the indigenous systems of medicine. Its 1923 report, one of the first major health reports in India, led Tamil physicians to organise and argue for Siddha as a system of its own.
Why it mattered. Historians see the 1920s as the moment Siddha emerged as a named, separate system.
Hakim Ajmal Khan, a physician and freedom fighter, led the building of a new college. Its foundation stone was laid in 1916, and Mahatma Gandhi opened it on 13 February 1921. It taught Unani and Ayurveda under one roof.
Why it mattered. It became a model for teaching Indian systems of medicine.
Harry G. Bartholomew and Maynard D. McFarlaneLondon and New York
The Bartlane system coded photographs as punched tape and sent them by submarine telegraph cable between London and New York. A picture that took a week by ship took hours.
Why it mattered. Pictures had become data: numbers for shades of grey, the same idea a digital fax uses.
June Mathis wrote the script for The Four Horsemen of the Apocalypse and pushed for an unknown actor, Rudolph Valentino, to star. She filled her scripts with settings and stage directions, not just a plot. She became the first woman executive at Metro.
Why it mattered. She showed that the writer's plan shapes the whole film, not just the words.
Loewi woke with an idea, lost it, dreamed it again and went straight to his lab. He stimulated the vagus nerve of one frog heart, which slowed, then dripped the fluid around it onto a second heart. That heart slowed too: the nerve had released a chemical. It proved to be acetylcholine.
Why it mattered. It proved nerves talk with chemicals, earning Loewi and Henry Dale the 1936 Nobel Prize.
Albert Calmette, Camille Guérin, Benjamin Weill-Hallé and Raymond TurpinParis, France
In Lille, Calmette and Guérin spent 13 years weakening a TB germ taken from cows, growing it again and again. In 1921 doctors in Paris gave the vaccine by mouth to a newborn baby whose mother had just died of TB. The baby stayed well.
Why it mattered. BCG is still given to babies in India and many other countries to protect them from severe TB.
The Romanian physiologist Nicolae Paulescu made a pancreatic extract he called pancreine and showed in 1921 that it lowered blood sugar in diabetic dogs. Historians still debate how much credit he deserves for insulin.
Why it mattered. It shows that the race to find insulin had several runners.
Frederick Banting, Charles Best and J. J. R. MacleodUniversity of Toronto, Canada
The young surgeon Frederick Banting and student Charles Best, working in John Macleod's lab, made extracts of dog pancreas that lowered blood sugar in diabetic dogs. Late in 1921 the biochemist James Collip joined to purify the extract.
Why it mattered. For the first time, the missing substance was in a bottle.
Loewi said an experiment came to him in a dream. Fluid from a frog heart slowed by its vagus nerve also slowed a second heart. Nerves must release a chemical, later identified as acetylcholine.
Why it mattered. It proved that nerves talk to other cells with chemicals: neurotransmitters.
Albert W. HullGeneral Electric, Schenectady, New York, USA
Hull studied a vacuum tube with a wire in the middle, a metal cylinder around it and a magnet outside. The magnet bends the electrons flying from the wire so they curl round instead of reaching the cylinder. He published papers and patents on this tube, now called a magnetron.
Why it mattered. Electrons spinning in a magnetic field are still the heart of every microwave oven's magnetron.
Frederick Banting, Charles Best, James Collip and John MacleodToronto
Fourteen-year-old Leonard Thompson was dying of type 1 diabetes when he was given an extract of insulin from animal pancreases. After Collip purified it, his blood sugar fell and he recovered. Banting and Macleod won the Nobel Prize in 1923.
Why it mattered. A disease that killed every child who got it became one people live with for a lifetime.
Frederick Banting, Charles Best, J.J.R. Macleod and James CollipUniversity of Toronto, Canada
In 1921 Banting and Best made an extract from the pancreas that lowered sugar in dogs. In January 1922, 14-year-old Leonard Thompson, close to death from diabetes, got the first injections; after Collip purified the extract, he recovered. Banting and Macleod won the Nobel Prize in 1923 and shared the money with Best and Collip.
Why it mattered. Type 1 diabetes changed from a death sentence into a disease people could live with.
Archibald Vivian Hill and Otto MeyerhofLondon and Kiel
A. V. Hill measured the tiny amounts of heat a muscle gives off as it contracts; Otto Meyerhof linked oxygen use to the making and removal of lactic acid. They shared the 1922 Nobel Prize in Physiology or Medicine. Hill went on to study how fast runners use oxygen, the idea behind VO2 max.
Why it mattered. Muscle energy became something you could measure.
Leonard Thompson, treated by the Toronto teamToronto General Hospital, Canada
Leonard Thompson, 14, was dying of diabetes. His first injection, on 11 January, was impure and did little. On 23 January he got Collip's purified extract, and his blood sugar fell towards normal. He lived another 13 years.
Why it mattered. Diabetes in children had been a death sentence. From then on, it was a condition people could live with.
Edmund Fowler and R. L. Wegel, Western ElectricNew York
The Western Electric 1-A was the first commercial electronic audiometer. It played pure tones from 32 Hz to about 16 kHz at controlled levels, so a doctor could chart exactly how well each ear heard. The cheaper 2-A followed in 1923.
Why it mattered. Hearing tests became numbers on a chart, the audiogram, instead of guesses with a ticking watch.
Poplawski filed a patent for a ‘beverage mixer’ on 18 February 1922, and it was granted on 15 January 1924 as US patent 1,480,914. A motor sat inside a stand, and a drinks container with a spinning agitator at its bottom sat on top. Putting the container on the stand switched the motor on and joined the two shafts together.
Why it mattered. Motor below, jar on top, blades at the bottom: this is still the shape of every blender and mixer grinder.
Howard Snyder invented a vaned agitator: a finned post in the middle of the tub that twisted back and forth and pushed water through the clothes. Maytag sold it in the Gyrafoam washer. By 1924, one in every five washing machines sold in America came from Maytag's factory.
Why it mattered. Moving water through clothes, instead of rubbing them, became the heart of the top-loading washer.
Dalén won the 1912 Nobel Prize in Physics, but lost his sight in an explosion that same year. At home he saw how tired his wife was from cooking, and he invented the AGA, a heavy cooker with two hotplates and two ovens that stays warm all day.
Why it mattered. It is a reminder that kitchens were designed around real work, mostly done by women.
Carrier unveiled the centrifugal chiller, which uses a fast-spinning wheel to compress refrigerant vapour. It was smaller, safer and more reliable than earlier machines for cooling big spaces.
Why it mattered. It made it practical to cool theatres, shops and offices full of people.
Lee de Forest showed his Phonofilm system, which recorded sound as a strip of light and dark on the film itself, right beside the pictures. Because sound and picture shared one strip, they could not drift apart.
Why it mattered. Sound-on-film became the way nearly every film carried sound for 70 years.
Kodak introduced 16 mm film as a cheaper, safer choice for amateurs, with a complete outfit of camera, projector, tripod, screen and splicer. Schools, explorers, news crews and documentary makers took it up. In 1969 the Swedish cinematographer Rune Ericson stretched its frame wider to make Super 16.
Why it mattered. Smaller film meant smaller cameras that one person could carry, which changed documentary and news forever.
Edgar Allen and Edward Doisy extracted a substance from pig ovary follicles that made the lining of the uterus grow and brought animals into their breeding cycle. It was oestrogen. Doisy later purified it, and progesterone was found a few years afterwards.
Why it mattered. It showed that the menstrual cycle is run by hormones from the ovary.
Banting, Macleod, Best and CollipStockholm, Sweden, and Toronto, Canada
Banting and Macleod won the 1923 Nobel Prize in Physiology or Medicine, and shared their prize money with Best and Collip. The inventors sold their insulin patents to the University of Toronto for $1 each, so that no one could lock it up. Drug makers such as Eli Lilly began making it in bulk that same year.
Why it mattered. It was one of the fastest Nobel Prizes ever, and insulin quickly reached patients around the world.
Compton bounced X-rays off electrons and found the X-rays lost energy exactly as if each photon were a tiny ball carrying momentum h ÷ λ. Momentum and energy were both conserved in every photon-electron collision.
Why it mattered. Light's momentum works photon by photon, the rule solar sails rely on.
Pennington, a chemist, became chief of a US government food research laboratory in 1907. She helped design refrigerated railway cars so milk, eggs and poultry stayed fresh on long journeys. In 1923 she founded the Household Refrigeration Bureau to teach families how to keep food safely cold at home.
Why it mattered. Fridges exist to keep food safe, and she turned the science of cold storage into everyday habits.
Berger recorded the first human electroencephalogram (EEG) through the scalp, finding a rhythm of about 10 waves a second when people rested with their eyes shut. He waited five years to publish.
Why it mattered. EEG is still how doctors diagnose epilepsy.
Alfred Newton Richards and Joseph WearnUniversity of Pennsylvania, Philadelphia
Using very fine glass pipettes, Richards and Wearn drew fluid straight out of Bowman's capsule in frogs. It had sugar and salt but no protein, just as filtration predicts.
Why it mattered. It settled an argument that had run for about 80 years: the glomerulus filters.
Haas passed a patient's blood through tubes of collodion membrane bathed in fluid for a short time. It did not save patients, but it showed that blood could be cleaned outside the body.
Why it mattered. It was the first step towards the artificial kidney.
Berger recorded tiny electrical waves from a person’s scalp, the first human electroencephalogram (EEG). He hesitated for five years and published in 1929. The rhythm he saw with eyes closed is the alpha wave.
Why it mattered. EEG let doctors watch the living brain’s activity, including in sleep and epilepsy.
Svedberg built centrifuges that spun samples so hard, many thousands of g, that big molecules settled out and could be watched and weighed. He showed that proteins such as haemoglobin have definite sizes, and won the 1926 Nobel Prize in Chemistry.
Why it mattered. Spinning became one of biology's main tools for sorting molecules and cells.
Stiebel founded the company Eltron and showed a coil immersion heater that warmed up and cooled down quickly. In 1927 or 1928 the company began making a small 1,000-watt electric instant water heater.
Why it mattered. Electric coils placed right in the water became the heart of both storage and instant electric geysers.
Livens, an engineer best known for weapons he designed in the First World War, invented a small dishwasher for the home. It had a door on the front for loading, a wire rack to hold the plates and a rotating sprayer to throw water over them.
Why it mattered. Front door, rack and spinning sprayer: almost every dishwasher since has followed this layout.
August Žáček and Erich HabannPrague, Czechoslovakia, and Jena, Germany
Working separately, the Czech physicist Žáček and the German physicist Habann found that a magnetron could do more than switch. It could oscillate and send out radio waves between about 100 MHz and 1 GHz. Žáček published first, but in a small journal that few people read.
Why it mattered. It turned the magnetron from a curiosity into a source of short radio waves.
Eisenstein's film about a 1905 naval mutiny cuts together hundreds of short shots. In the Odessa Steps sequence, soldiers march down a long flight of steps into a fleeing crowd, and the editing stretches a few moments of terror into minutes.
Why it mattered. It became the most studied example of montage: meaning and emotion made by shots colliding.
Frederick BarringtonUniversity College London, England
Barrington found a small area in the brainstem of cats that, when damaged, stopped normal emptying of the bladder. It is now called Barrington's nucleus, or the pontine micturition centre.
Why it mattered. It located the “go” switch that your cortex learns to hold.
Baird showed moving silhouettes on his mechanical television to shoppers at Selfridges. The pictures were only outlines, with no shades of grey. Later that year, in his attic lab, he got a greyscale picture of a ventriloquist’s dummy called Stooky Bill.
Why it mattered. It was one of the first times the public saw moving pictures sent by wire.
Willis Carrier and Adolph ZukorRivoli Theatre, New York, USA
Carrier's system opened at the Rivoli on Broadway. The film studio boss Adolph Zukor watched the fanning crowd grow calm and reportedly said: “Yes, the people are going to like it.” Within about five years Carrier had cooled more than 300 cinemas.
Why it mattered. Cinemas became summer escapes, and the summer blockbuster was born.
Werner Heisenberg and Erwin SchrödingerGöttingen and Zürich
Inside atoms, electrons do not follow neat Newtonian paths. Heisenberg in 1925 and Schrödinger in 1926 found new rules, quantum mechanics, for the very small.
Why it mattered. It marked the second border of Newton's world, the size of atoms.
Gotthilf Betulander; Bell Telephone LaboratoriesSweden and the USA
Crossbar switches store the dialled number first, then close a single crosspoint in a grid of horizontal and vertical bars. Sweden used Betulander's design from 1926; the US No. 1 crossbar entered service in 1938.
Why it mattered. Crossbar was faster and more reliable than step-by-step, and ran many networks until the digital age.
Reiniger animated black paper silhouettes with hinged joints, frame by frame on a lit table, for The Adventures of Prince Achmed. It took about three years.
Why it mattered. It is the oldest surviving animated feature film, and it made cut-out animation an art.
Reiniger cut her characters from black card with hinged joints, moved them frame by frame over lit glass, and used layers of glass for depth. The Adventures of Prince Achmed took about three years.
Why it mattered. It is the oldest surviving animated feature, and a direct ancestor of today’s cut-out rigs.
Don Juan opened with a recorded orchestral score and sound effects played from large discs, one 16-inch record for each reel of film, turning at 33⅓ rpm. If a projectionist started a disc late, the whole reel was out of sync.
Why it mattered. It proved audiences would pay for recorded film sound.
Reiniger cut her characters from black card and moved them frame by frame under the camera for The Adventures of Prince Achmed. It took about three years to make.
Why it mattered. It is the oldest surviving animated feature film, made by one of animation's first great directors.
About 40 members of the Royal Institution climbed the stairs to Baird’s lab to see live faces on a small screen. His system used spinning discs and about 30 lines, with a picture that flickered but moved. The receiver he used is now in the Science Museum.
Why it mattered. It is widely called the first demonstration of true television: live, moving and in shades of grey.
Working on his own, far from Europe and America, Takayanagi sent the katakana letter イ (i) to a cathode-ray tube screen. He used a Nipkow disc to scan and a CRT to show, with 40 lines. He is called the father of Japanese television.
Why it mattered. It was one of the first pictures ever shown on an electronic screen.
Hobart, the company that made KitchenAid mixers, bought the Crescent Washing Machine Company, which Cochrane had founded. She had died in 1913, but her dishwashers lived on.
Why it mattered. It linked Cochrane's invention to one of the best-known kitchen brands in the world.
Kinjiro Okabe, in Hidetsugu Yagi's laboratoryTohoku Imperial University, Sendai, Japan
Okabe, one of Yagi's first doctoral students, split the magnetron's metal cylinder into halves. This let it make much shorter waves, and he won a US patent for it in 1929. Later, in Osaka, he reached waves about 12 cm long, close to the waves in a kitchen microwave today.
Why it mattered. Japan's early magnetron research started worldwide interest in centimetre waves.
The film industry, with the arrival of sound filmsUnited States
When films gained soundtracks in the late 1920s, projectors had to run at one steady speed so voices sounded right. The industry settled on 24 frames per second, which is still the standard for cinema.
Why it mattered. A single minute of film is 1,440 separate pictures, which is why video is so much bigger than one image.
AT&T and the British General Post OfficeNew York and London
The first commercial telephone service between North America and Europe opened, carried by radio. A three-minute call cost about 75 US dollars at the time.
Why it mattered. For the first time, voices crossed an ocean the same day, not weeks later by ship.
Lee de Forest; Theodore Case and Earl SponableNew York and Hollywood
Lee de Forest's Phonofilm showed sound-on-film shorts in New York in 1923. Fox's Movietone system, by Case and Sponable, put the sound as a strip of light and dark next to the pictures, and Sunrise (1927) was the first professional feature with an optical soundtrack. A lamp and a light sensor in the projector turned that strip back into sound.
Why it mattered. Sound needed a fixed speed, so 24 frames a second became the standard that cinemas still use.
For Metropolis, Schüfftan set a mirror at 45° in front of the camera. It reflected small model buildings, while part of its silver was scraped away so the camera could see real actors through the glass. Both were filmed in one shot.
Why it mattered. It showed that a big world could be joined to real actors inside the camera, with nothing added later.
Eugen Schüfftan, for Fritz Lang's MetropolisBerlin, Germany
Metropolis needed actors walking among huge skyscrapers. Schüfftan put a mirror at 45 degrees in front of the camera, scraped away part of its silver, and reflected small models while real actors showed through the clear part. On screen they seemed to share one giant city.
Why it mattered. It was an early way to extend a set far beyond what was actually built, the job digital set extension does today.
The Jazz Singer was mostly a silent film with a Vitaphone score, but in a few scenes Al Jolson sings and speaks in sync. The line "You ain't heard nothin' yet" thrilled audiences, and the film broke box-office records.
Why it mattered. It is traditionally credited with launching the talkie revolution.
Eugen Schüfftan, for Fritz LangBabelsberg, near Berlin
For Metropolis, Schüfftan placed a specially made mirror at an angle in front of the camera. Part of the mirror reflected a small model city, and part was scraped clear so the camera could see real actors behind it. In one shot, actors seemed to stand inside giant buildings.
Why it mattered. The Schüfftan process joined miniatures and live actors in the camera itself, and was still used decades later.
Peter Mole and Elmer RichardsonHollywood, California
When films began to talk, the noisy carbon arcs were a problem on closed sound stages. New panchromatic film could see red light, so warm tungsten bulbs now worked well. Peter Mole and Elmer Richardson founded Mole-Richardson in Hollywood in 1927 to build incandescent studio lights, and in 1928 the new Academy studied incandescent lighting.
Why it mattered. Quiet incandescent lamps, nicknamed inkies, became the everyday tools of the Hollywood studio.
Silent films were often cranked at around 16 to 20 frames a second, and speeds varied. A soundtrack must run at a steady speed, so the industry settled on 24 frames every second. At 24 fps, 1,000 feet of 35 mm film lasts about 11 minutes.
Why it mattered. 24 fps is still the heartbeat of cinema, even on digital cameras.
Otto Hunte, Erich Kettelhut and Karl VollbrechtBerlin, Germany
Fritz Lang's Metropolis needed a whole future city. Three art directors designed it, mixing modern, art deco and Gothic ideas. The look was partly inspired by Lang's visit to New York.
Why it mattered. It proved that designers could build a believable world that did not exist yet.
The Jazz Singer played its songs and a few lines of speech from discs kept in sync with the film. Audiences were thrilled, and within a few years almost every film had sound. A soundtrack needs a steady speed, so 24 frames a second became the standard.
Why it mattered. Synchronised sound changed how films were acted, shot and edited.
Cyrus Fiske and Yellapragada Subbarow (and independently Karl Lohmann, and Philip and Grace Eggleton)Boston
At Harvard, Fiske and the Indian biochemist Yellapragada Subbarow discovered phosphocreatine in muscle in 1927 and, in 1929, ATP. Karl Lohmann in Germany found ATP the same year, and the Eggletons in London found "phosphagen" too.
Why it mattered. ATP is the energy coin every myosin stroke spends; phosphocreatine is the quick reserve behind a sprint.
After several failed attempts, Moniz injected a dye that shows up on X-rays into the carotid artery of a patient and took pictures of the brain's vessels. Leg arteries had been imaged a few years earlier, but this was the first cerebral angiogram.
Why it mattered. Angiography let doctors see blocked or burst vessels without surgery.
At the Bristol sessions in 1927, the Carter Family made their first records. Maybelle Carter, then 18, played the melody on the low strings with her thumb while brushing the high strings for rhythm. Her style became known as the Carter scratch.
Why it mattered. She showed that one guitar could play melody and rhythm at once, and generations of guitarists copied her.
John Dopyera and George BeauchampLos Angeles, California, USA
John Dopyera built guitars with thin aluminium cones under the bridge, working like loudspeakers. He and George Beauchamp founded the National String Instrument Corporation in 1927. In 1928 Dopyera and his brothers started Dobro, whose single cone was cheaper and louder.
Why it mattered. Guitarists were desperate to be heard over horns and drums, and this was the loudest answer before electricity.
General Electric and Christian SteenstrupSchenectady, New York, USA
General Electric's Monitor-Top had its compressor sealed in a round steel case on top, designed by chief engineer Christian Steenstrup, who had come to the US from Denmark. It was named after the gun turret of the Civil War ironclad USS Monitor. It first sold for about $525, prices soon fell toward $200, and over a million were made.
Why it mattered. A sealed, reliable machine turned the fridge into an ordinary household appliance.
Philo Farnsworth, with Elma “Pem” Farnsworth202 Green Street, San Francisco, USA
Farnsworth said he got the idea of scanning line by line as a teenager ploughing a field. At 21 his image dissector camera tube sent a simple straight line to a screen in the next room. There were no moving parts anywhere.
Why it mattered. It was the first all-electronic television picture, from camera to screen.
Back from holiday, Fleming saw that a mould growing on one of his dishes had killed the bacteria around it. He named the substance penicillin. It became a medicine only in 1940–41, when Howard Florey, Ernst Chain and Norman Heatley in Oxford purified it and tested it.
Why it mattered. Antibiotics turned deadly infections into curable ones.
Steamboat Willie was one of the first cartoons with a fully synchronised soundtrack. Music and effects were planned beat by beat on sheets before the drawings were made.
Why it mattered. Sound meant timing to the frame, and soon lip sync, planned on bar sheets and exposure sheets.
Fleming noticed that a mould growing on a dish of bacteria had killed the bacteria around it. The substance, penicillin, was turned into a medicine in the 1940s by Howard Florey, Ernst Chain and colleagues. Fleming warned that misuse could make bacteria resistant.
Why it mattered. Antibiotics help the immune system against bacteria, but not against viruses.
Andrew Ivy and Eric OldbergNorthwestern University, Chicago
Ivy and Oldberg found that an extract of the upper intestine made the gallbladder of dogs contract. They named the messenger cholecystokinin, “the gallbladder mover”. It was later shown to call for pancreatic enzymes too.
Why it mattered. It explained how bile arrives just when fat does.
Polio could paralyse the muscles used for breathing. Drinker and Shaw built a sealed metal tank that lowered and raised the air pressure around a patient's body, so air flowed in and out of the lungs. Its first patient was an eight-year-old girl at Boston Children's Hospital.
Why it mattered. It copies the pressure trick your own chest and diaphragm use every time you breathe in.
Telephone engineers needed a unit for how much a signal fades along a line. In 1928 their "transmission unit" was renamed the decibel, a tenth of a bel, in honour of Alexander Graham Bell.
Why it mattered. The same log scale now measures everything from a whisper to a jet engine.
Polio could paralyse the muscles used for breathing. Drinker and Shaw built a sealed metal tank that lowered and raised the air pressure around a patient’s body, so air flowed in and out of the lungs. Its first patient was an eight-year-old girl at Boston Children’s Hospital.
Why it mattered. Iron lungs kept thousands of polio patients alive, and they copy the same pressure trick your own chest uses.
Martenot had noticed the pure tones made when military radio oscillators overlapped. He built an instrument played by sliding a ring along a wire, and later a keyboard that wobbles sideways for vibrato. It was first heard at the Paris Opera, and the composer Olivier Messiaen later made it a star of his Turangalîla-Symphonie.
Why it mattered. It gave composers an electronic voice they could shape with the same care as a violin.
Baird used discs with red, green and blue filters to send the world’s first colour television pictures. The same year his team sent a picture across the Atlantic. Mechanical TV was clever, but the pictures stayed small and blurry.
Why it mattered. Mixing red, green and blue is still how every colour screen works.
Dziga Vertov and editor Elizaveta SvilovaKyiv, Odesa and Moscow, USSR
A city symphony with no story and no actors, built from thousands of shots, with fast cutting, split screens and freeze frames. Svilova, the editor, even appears in the film at her editing bench.
Why it mattered. It shows off almost every editing trick of the silent era in one film.
Universal turned its part-talkie musical Show Boat into a sound film, and Jack Foley and a small team performed footsteps and other sounds live while watching the film projected. His way of working spread to every studio.
Why it mattered. Artists who add everyday sounds in sync with the picture are still called Foley artists.
Menzies, a trained illustrator, won the very first Academy Award for art direction for The Dove and The Tempest. He planned how films should look with his own drawings.
Why it mattered. Designing a film's look was now recognised as a craft of its own.
Forssmann, a junior doctor, slid a thin tube into a vein in his own arm and pushed it up into his heart, then walked to the X-ray room to photograph it. His bosses thought it a stunt. In 1956 he shared a Nobel Prize for it.
Why it mattered. It began cardiac catheterisation, now used to find and open blocked arteries.
Von Neergaard found that lungs filled with liquid inflate far more easily than lungs filled with air. He reasoned that surface tension in the wet lining of the air sacs pulls them shut, and guessed something must lower it.
Why it mattered. His idea was ignored for about 25 years, but it was the first clue to surfactant.
Forssmann, a young junior doctor, slid a thin tube into a vein in his own arm and pushed it up into his heart. He then walked to the X-ray room to take a picture of it. His bosses thought it was a stunt, and he was dismissed from his next job.
Why it mattered. It showed a tube could safely reach the heart, the start of cardiac catheterisation.
Lonsdale, born in Ireland, used X-ray crystallography to prove that the benzene ring, a building block of many chemicals, is flat. Chemists had argued about its shape for decades. In 1945 she became one of the first two women elected to the Royal Society.
Why it mattered. It showed X-rays could settle arguments about the shapes of molecules.
Miele built a round metal tub with baskets for plates and cutlery. You filled it with hot water by hand, then an electric motor spun a propeller at the bottom that sprayed water over the dishes for several minutes.
Why it mattered. It brought the electric dishwasher to European homes, and Miele went on to make more than 20 million of them.
Fox became the first studio to use rear projection in its films Liliom and Just Imagine. A projector behind a translucent screen played filmed scenery while actors performed in front of it. New film stock, brighter lamps and motors that kept camera and projector in step made it possible.
Why it mattered. Backgrounds could now be shot anywhere and brought onto the stage, the first 'virtual location'.
Wever and Bray wired up a cat's auditory nerve to a telephone receiver in another room and heard speech spoken into the cat's ear. Most of the signal later turned out to come from the hair cells themselves: the cochlear microphonic.
Why it mattered. It proved the inner ear turns sound into electrical signals that follow the sound wave.
Alessandro Vallebona; Bernard Ziedses des PlantesGenoa; Utrecht
Vallebona built a machine that moved the X-ray tube and film in step, so only one layer of the body stayed sharp; he called it stratigraphy. A year later the Dutch radiologist Ziedses des Plantes described his own version, planigraphy. Several people in different countries claimed the idea around this time.
Why it mattered. Doctors could now pick out a single slice, but the other layers still smeared across the picture.
Reports of a Berlin family killed by toxic gas leaking from a fridge's seal led the two physicists to design an absorption fridge with no moving parts. They applied for a US patent in December 1927, and patent 1,781,541 was granted on 11 November 1930. Electrolux bought some of their patents, but the fridge was never sold.
Why it mattered. Leaky, poisonous refrigerants were a real danger, and even the world's most famous scientist tried to fix it.
Thomas Midgley Jr., Albert Henne and Robert McNaryDayton, Ohio, USA
Early fridges used gases like sulfur dioxide, methyl formate and ammonia, which are toxic, and leaks killed people. A General Motors team made dichlorodifluoromethane, the first CFC, sold as Freon. In 1930 Midgley breathed some in and blew out a candle to show it was neither poisonous nor flammable.
Why it mattered. Safe refrigerants let fridges into every home, but no one yet knew what they would do to the sky.
Shibaura Engineering Works (later Toshiba)Tokyo, Japan
Toshiba says it released Japan's first electric washing machines in 1930. The Solar washer was based on the American Thor agitator machine, which had been imported to Japan a few years earlier.
Why it mattered. The electric washer was becoming a global machine, and Japan would later lead the world in making them.
Thomas Midgley Jr., Albert Henne and Robert McNaryDayton, Ohio, USA
Early refrigerants like ammonia and sulfur dioxide were toxic, and leaks killed people. A General Motors team made dichlorodifluoromethane, the first CFC, sold as Freon. In 1930 Midgley breathed some in and blew out a candle to show it was neither poisonous nor flammable.
Why it mattered. Safe refrigerants let air conditioners into homes and cars, but no one yet knew what they would do to the sky.
In beta decay, electrons shot out of atoms with less energy than they should have. Niels Bohr was even willing to give up energy conservation. Pauli wrote an open letter to physicists meeting in Tübingen suggesting that an invisible, uncharged particle carries away the missing energy. Enrico Fermi built a full theory around it in 1933 to 1934 and named it the neutrino.
Why it mattered. Instead of breaking the law, physicists trusted it enough to predict a new particle.
Racer Tullio Campagnolo, the story goes, lost time in a race struggling to undo frozen wing nuts with cold hands. He invented a lever that frees a wheel in seconds.
Why it mattered. Quick changes of wheels and tyres became normal.
Salimuzzaman SiddiquiTibbiya College research institute, Delhi
Working at the institute Ajmal Khan founded, the chemist Salimuzzaman Siddiqui isolated alkaloids from Rauvolfia serpentina and named one ajmaline after Ajmal Khan. It is still used to test for a heart rhythm disorder.
Why it mattered. A plant used in traditional medicine gave a modern, tested drug.
The Ayurvedic physician Gananath Sen and the doctor Kartick Chandra Bose reported that powdered Rauvolfia serpentina root calmed disturbed patients and lowered blood pressure. The same year the chemist Salimuzzaman Siddiqui isolated its first alkaloids.
Why it mattered. It started the path from a traditional herb to a modern drug.
Alam Ara, India's first sound film, premiered in Bombay. Its sound was recorded straight onto the film with a single-system camera. Cinemas across India had to fit sound heads and speakers to their projectors to show the new talkies.
Why it mattered. Songs and dialogue became the heart of Indian cinema, and projectors everywhere had to learn to play them.
Alam Ara opened at the Majestic Cinema in Bombay. It was recorded with the Tanar single-system recorder, and because trains ran past the studio it was shot mostly between about 1 and 4 in the morning. Its seven songs made music part of Indian cinema from the start.
Why it mattered. It began India's sound era, and no print of it survives.
Swiss-born Albert Hurter joined Disney and spent about ten years drawing whatever he liked: odd creatures, cottages, trees and moods. The animators used his sketches as a starting point. He is widely described as Disney's first inspirational sketch artist.
Why it mattered. It created a job whose only purpose was to spark ideas for everyone else.
Irani shot Alam Ara with the sound recorded on the film itself, mostly at night to avoid street noise. Its songs were such a hit that songs became part of almost every Indian film.
Why it mattered. It began Indian sound cinema and its song-and-dance tradition.
Fox was pouring a powder called PTC when some of it blew into the air. His colleague C. R. Noller complained it was very bitter; Fox, standing closer, tasted nothing. Testing others showed that people differ: roughly a third of people worldwide cannot taste it.
Why it mattered. It was the first clear sign that taste is partly in our genes. The gene, TAS2R38, a bitter receptor, was found in 2003.
Swiss physicist Auguste Piccard rode a sealed, pressurised cabin under a hydrogen balloon to about 15,781 m, higher than anyone before. The same idea, a float lighter than the fluid around it, later took him down into the sea.
Why it mattered. It carried people into the stratosphere on buoyancy alone.
George Beauchamp, Paul Barth and Adolph RickenbackerLos Angeles, California, USA
George Beauchamp and Paul Barth built a pickup: a coil of wire under the strings, with two horseshoe magnets arching over them. Adolph Rickenbacker’s company made it from cast aluminium from 1932, as a lap steel guitar nicknamed the Frying Pan. The patent came in 1937.
Why it mattered. It is widely considered the first commercially successful electric guitar.
Kistler found a way to dry a jelly without letting it collapse, leaving a solid made almost entirely of tiny trapped pockets of air. He described these aerogels in the journal Nature in 1931. They are so light and cloudy that people nickname them frozen smoke.
Why it mattered. Air trapped in tiny pores cannot flow, so aerogels are among the best heat insulators ever made.
Edgerton developed the electronic stroboscopic flash, with bursts of light lasting a tiny fraction of a second, and photographed bullets, milk drops and hummingbirds in mid-motion.
Why it mattered. Electronic flash is in almost every camera and phone.
Technicolor's new camera split the light with a prism onto three strips of black-and-white film, one each for red, green and blue. Disney's cartoon Flowers and Trees was the first film released in this full three-colour process. It won the first Academy Award for a cartoon short.
Why it mattered. Colour on screen became something you could design and control, not just add afterwards.
Flowers and Trees was the first commercial film in three-strip Technicolor, with cels painted in full colour. It won the first Academy Award for an animated short.
Why it mattered. Colour made ink-and-paint departments, and colour styling, a big part of animation.
Mitchell, founded in 1919, made the Standard studio camera and in 1932 the quieter NC. A soundproofed version, the BNC, followed in the 1930s. For decades these heavy, precise cameras shot a large share of Hollywood films.
Why it mattered. Quiet cameras let actors speak on set without the camera noise ruining the sound.
Technicolor's camera used a prism to split the light into three beams, each exposing its own black-and-white film for red, green or blue. Disney's cartoon Flowers and Trees (1932) was first, and Becky Sharp (1935) was the first feature shot entirely this way.
Why it mattered. It showed that full colour could be built from three separate records of light, the same idea a digital sensor uses.
Frances Marion won Academy Awards for writing The Big House (1930) and The Champ (1931). She was the first writer, man or woman, to win two. In the 1920s she was the best-paid screenwriter in Hollywood.
Why it mattered. Screenwriting had become a respected profession, and women were leading it.
Technicolor's three-strip camera split the light into red, green and blue records on three films. Disney's cartoon Flowers and Trees (1932) used it first, and Becky Sharp (1935) was the first feature made entirely with it.
Why it mattered. It gave cinema rich, lasting colour, the ancestor of the colour grading done today.
Working with thin slices of liver, Krebs and his student Henseleit showed that ornithine is used and then given back as ammonia is turned into urea. It was the first metabolic cycle ever found.
Why it mattered. It explained how the liver makes toxic ammonia safe.
Krebs and his student Henseleit fed slices of liver different chemicals and measured the urea they made. Adding a substance called ornithine made urea pour out, yet the ornithine was not used up. They worked out a loop of reactions that turns toxic ammonia into harmless urea.
Why it mattered. It was the first metabolic cycle ever discovered, and it explains why liver failure can poison the brain.
The doctor Rudolf Schindler and the instrument maker Georg Wolf built a semi-flexible gastroscope, with many small lenses in a tube that could bend a little. It made looking into the stomach much safer.
Why it mattered. It turned gastroscopy into an everyday test for the first time.
George Beauchamp and Paul BarthLos Angeles, California
Beauchamp's 'Frying Pan' guitar had magnets and a coil around its steel strings. As a string vibrates it changes the magnetism through the coil and induces a tiny current that an amplifier makes loud. Prototype 1931, sold from 1932.
Why it mattered. Every electric guitar pickup is a tiny Faraday generator.
Schultz and Sherman designed a unit that sat on a window ledge. It went on sale in 1932 for $10,000 to $50,000, far more than a house, so almost no one bought one.
Why it mattered. The shape was right, and the window unit became the most common room air conditioner.
Willis O'Brien and the RKO effects teamRKO studios, Los Angeles, USA
King Kong combined live actors with stop-motion monsters using rear projection. Fay Wray spent many hours in a fake tree while the animated battle was projected behind her. The team even built tiny screens into their miniature sets to project the actors into them.
Why it mattered. Rear projection became the standard way to put actors into worlds that did not exist.
Rear projection was dim, so the picture faded on big screens. At Paramount, Edouart refined the process, for example running three projectors in sync on the same background plate to make it brighter and more even.
Why it mattered. Brightness has been the problem of every screen-based stage since, LED walls included.
John P. Fulton, for The Invisible ManUniversal Studios, California, USA
To make a man with no body, the actor wore black velvet in front of black velvet walls, so only his clothes showed. The pieces were combined with travelling mattes. Fulton said about 63,000 frames were retouched by hand to hide the mistakes.
Why it mattered. It shows how much patient hand work has always been behind effects, long before computers.
Kong was a small puppet with a metal armature and rabbit fur, animated a frame at a time and combined with live actors using rear projection and other tricks.
Why it mattered. It is widely regarded as a milestone of stop-motion, and it inspired a generation of animators.
Willis H. O'Brien; Marcel DelgadoRKO studios, Los Angeles
The Kong that climbs the skyscraper was a puppet only about 14 to 18 inches tall, made of a metal skeleton padded with cotton, latex and rabbit fur. O'Brien's team moved it a tiny bit for every frame, a method called stop-motion. For close-ups they also built a giant mechanical head covered in bearskins.
Why it mattered. It proved a puppet could become a movie star that audiences cared about.
Webb Smith, Walt Disney ProductionsHyperion studio, Los Angeles, USA
Disney credited the story man Webb Smith with drawing each scene on its own sheet and pinning the sheets up in order on a board. The whole team could now see the story at a glance and move scenes around. The first complete storyboards are usually said to be for the short Three Little Pigs (1933).
Why it mattered. The storyboard was born: a story you can read like a comic and rearrange with pins.
Harvey Fletcher and Wilden MunsonBell Labs, New York
Fletcher and Munson measured how strong tones of different pitches must be to sound equally loud. Ears turned out to be far less sensitive to low and very high pitches than to the middle. Their curves became today's standard, ISO 226.
Why it mattered. It is why sound meters use weightings like dB(A), and why music sounds thin when played quietly.
Meissner and Ochsenfeld found that a metal cooled into its superconducting state expels a magnetic field from inside itself. Superconductivity itself had been found by Heike Kamerlingh Onnes in 1911. Today superconducting coils make MRI fields, and magnets can float above cold superconductors.
Why it mattered. It showed superconductors are more than perfect wires: they are also near-perfect magnetic shields.
T. R. Mahalingam, known as Mali, gave his first concert at a festival in Chennai when he was only seven. He later used an eight-hole bamboo flute and new cross-fingerings, and he made the flute bend and slide between notes like a singing voice. Most Carnatic flute players today follow the style he created.
Why it mattered. He showed a bamboo flute could copy every curve of the human voice in South Indian music.
Vladimir Zworykin and team, building on Kálmán TihanyiWestinghouse and RCA, USA; Budapest, Hungary
Zworykin, who had filed a TV patent in 1923, showed the iconoscope camera tube to the press in June 1933. It collected light across a whole picture between scans, which made it far more sensitive. The Hungarian Kálmán Tihanyi had patented this charge-storage idea in 1926, and RCA bought his patents.
Why it mattered. Sensitive electronic cameras made studio television practical.
As electric fans spread in the 1920s and 1930s, fan-driven hoods began to replace simple open ones over stoves. Vent-A-Hood, which calls itself the first maker of home range hoods, started in 1933, building hoods in a house with a dirt floor and selling them door to door. Its fan was a centrifugal blower.
Why it mattered. A motor and blower above the stove turned the old smoke hood into the electric kitchen chimney.
WestinghouseCentury of Progress World's Fair, Chicago, USA
Westinghouse cooked food between two metal plates connected to a 10 kW shortwave radio transmitter. The waves were about 5 m long, at 60 MHz, far longer than a modern microwave oven's.
Why it mattered. It showed that radio energy could heat food, years before anyone had a small, powerful source of shorter waves.
Japanese physiologist Yas Kuno spent his life measuring sweat, using a device that weighed the water leaving a patch of skin every few minutes. His 1934 book The Physiology of Human Perspiration was the first work on body temperature control from Japan. He showed there are two kinds of sweating: for heat, and for nerves.
Why it mattered. It explained how evaporating sweat lets skin cool the whole body.
In the first volume of the Proceedings of the Indian Academy of Sciences, Raman described the drums in more detail. He showed that the drumhead can split into patterns that act like a string divided into one, two, three, four or five parts. That gives five tones in harmonic order, while the higher, messier tones die away.
Why it mattered. It turned drum makers' old craft into physics anyone could test.
In 1928 a fire badly burned two fingers of Django Reinhardt’s left hand. He taught himself to play again using mostly his index and middle fingers. In 1934 he and violinist Stéphane Grappelli formed the Quintette du Hot Club de France.
Why it mattered. It was among the first jazz bands to put the guitar out in front as a lead instrument.
C. A. Tannahill (some sources say J. F. Cantrell)Fort Worth, Texas, USA
A shop opened where people could rent electric washing machines by the hour. It had just four machines, and an attendant switched them on because coin slots had not yet arrived. It was called a 'washateria', a mix of washing and cafeteria.
Why it mattered. Families who could not afford a machine could still use one, an idea that became the laundromat and the launderette.
GM put independent front suspension, sold as 'Knee-Action', across its car lines. Cadillac, Buick and Oldsmobile used big coil springs; Chevrolet and Pontiac used the Dubonnet system with coils in a sealed unit.
Why it mattered. Coil springs at each front wheel became the normal way to build a comfortable car.
Coandă patented a way to bend a jet of fluid by running it along a curved surface. He had noticed the effect years earlier, when flames from his experimental plane seemed to cling to its sides.
Why it mattered. The Coandă effect holds a ball in a hair-dryer jet and helps explain many 'Bernoulli' tricks.
Rouben Mamoulian, with Technicolor and colour consultant Natalie KalmusHollywood, USA
Becky Sharp was the first feature film made entirely in three-strip Technicolor. Technicolor sent a colour consultant to every film, often Natalie Kalmus, to control how colours were used. She often pushed for calmer colours instead of a riot of bright ones.
Why it mattered. It made colour a job with its own expert, a bit like a colourist today.
German companies built editing tables that lay the film flat on spinning plates, with a screen and separate picture and sound tracks. They came into wide use in the United States in the 1970s.
Why it mattered. Flatbeds made it easy to run picture and sound together, forwards and back, and became the classic editing bench.
Nitin Bose, Raichand Boral and Mukul BoseNew Theatres, Calcutta (Kolkata), India
For the Bengali film Bhagya Chakra and its Hindi version Dhoop Chhaon, the songs were recorded first and actors mimed to them on set. Director Nitin Bose had the idea, with music director Raichand Boral and sound recordist Mukul Bose.
Why it mattered. Playback singing became the heart of Indian film music, a form of the same lip sync ADR uses.
Augustin Fresnel designed a lens of thin stepped rings for French lighthouses; one was tested in 1822 and the first was lit at Cordouan in 1823. Mole-Richardson put a stepped Fresnel lens in front of a tungsten lamp so the beam could be focused from narrow to wide. Its Solarspot won a technical Academy Award for 1935.
Why it mattered. The Fresnel spotlight, with a beam you can spot or flood, is still the classic film light.
Technicolor's three-strip camera split the light three ways onto three films. Disney used it for the cartoon Flowers and Trees in 1932, and in 1935 Becky Sharp, shot by Ray Rennahan, became the first feature filmed entirely this way. The camera worked at about ASA 5, so sets were blasted with carbon arcs: one actor on The Wizard of Oz (1939) recalled about a thousand foot-candles, and the sets often passed 100 °F (38 °C).
Why it mattered. Colour film made light levels, and light colour, a central part of the cinematographer's job.
The term concept art is often said to come from Disney, which used it as early as the 1930s. At the studio, artists painted ideas for scenes long before animation began. Many different ideas were tried before one was chosen.
Why it mattered. It gave a name to a stage of filmmaking that is now in almost every big film and game.
Disney's artists photographed their storyboard drawings and cut them together on film, each held for as long as the finished shot would last. They added dialogue and music, so the team could watch the whole cartoon before animating it. This was called a Leica reel, or story reel.
Why it mattered. It is the ancestor of every animatic and computer previs made today.
Smith and his colleagues used inulin, a sugar that is filtered but neither taken back nor added by the tubules, to measure how fast the kidneys filter. His 1951 book The Kidney gathered what was known.
Why it mattered. It gave doctors a way to put a number on kidney function, like the eGFR used today.
The Hammond organ made its sound with spinning metal tonewheels next to magnetic pickups. Sliding drawbars let the player mix in different harmonics, a little like mixing colours of paint. More than 1,750 churches bought one in its first three years.
Why it mattered. Drawbars are additive synthesis you can touch: you build a sound by stacking pure tones.
Protons push each other apart, so what holds an atom's centre together? Yukawa proposed a very strong, very short-range force carried by a new particle, later called the meson. The particle was found in 1947, and he won the Nobel Prize in 1949.
Why it mattered. It showed that a force can be carried by a particle, an idea behind all of modern physics.
Hollmann patented a magnetron with several resonant cavities, an early version of the design that would later change radar. The German military turned it down because its frequency drifted, and built radar with a different tube instead.
Why it mattered. Good ideas need the right moment: the cavity idea only took off five years later in England.
In his paper 'On Computable Numbers', 24-year-old Alan Turing imagined a simple machine that reads and writes symbols on a long tape, following a table of rules. He showed that one universal machine could imitate any other, just by being given its rules.
Why it mattered. It is the idea behind every computer: one machine, many programs.
Hans Selye noticed that rats hurt in very different ways, by cold, injury or drugs, all showed the same changes, including swollen adrenal glands. He described this in a short letter to Nature. He later called it stress.
Why it mattered. It showed that hormones help the whole body respond to any kind of danger.
Harold HimsworthUniversity College Hospital, London, England
Himsworth tested how people with diabetes responded to glucose and insulin together. Some were very sensitive to insulin; others were 'insulin-insensitive'. This split grew into what we now call type 1 and type 2 diabetes.
Why it mattered. It was the first big step towards understanding insulin resistance.
In 1936 Gibson launched the ES-150, a hollow Spanish-style guitar with a pickup, sold with an amplifier. Charlie Christian bought one and in 1939 joined Benny Goodman’s band. Now a guitar was loud enough to take solos in a big band.
Why it mattered. It was the first commercially successful Spanish-style electric guitar, and its pickup became known as the Charlie Christian pickup.
A. O. Smith had learned to fuse glass onto steel to make huge tanks for breweries. In 1936 it patented a glass-lined water heater, and in 1939 it began mass-producing them for homes.
Why it mattered. A thin coat of glass keeps hot water off the steel, so tanks last many more years before they rust and leak.
Measuring haemoglobin in a magnetic field, Pauling and Coryell found that it is weakly repelled when it carries oxygen, but weakly pulled in when it has given the oxygen up.
Why it mattered. Fifty-four years later this difference became the BOLD signal that lets fMRI watch the brain at work.
In 1936 the Dutch physicist Cornelis Gorter tried to detect nuclear magnetic resonance in solids and failed. Around 1941 Yevgeny Zavoisky in Kazan saw signals that may have been NMR, but the field of his magnet was not uniform enough to repeat them reliably. In 1944 he discovered the related electron spin resonance instead.
Why it mattered. The effect was real but faint, and finding it needed better magnets and radio electronics.
BBC, with Marconi-EMI and BairdAlexandra Palace, London, UK
The BBC began a regular “high-definition” service from Alexandra Palace. Two systems took turns: Baird’s 240-line system and Marconi-EMI’s all-electronic 405 lines. In 1937 the BBC chose the electronic one.
Why it mattered. It is widely called the world’s first regular high-definition TV service.
Kiichiro Toyoda, son of a loom inventor, started a car department inside his family's weaving-machine company. Its first passenger car, the Model AA, was shown in 1936. In August 1937 the department became the Toyota Motor Company.
Why it mattered. Toyota grew into one of the world's biggest carmakers and later built the first mass-produced hybrid.
The Kine Exakta is widely considered the first 35 mm single-lens reflex (SLR): a mirror shows you exactly what the lens sees, then flips up out of the way when you take the picture.
Why it mattered. Zahn's 1685 mirror, now inside a camera. SLRs dominated serious photography for half a century.
In his master's thesis, Claude Shannon showed that circuits of on/off switches follow Boole's algebra. A switch that is on is 1, a switch that is off is 0, and wiring them together can add numbers.
Why it mattered. It joined logic to electricity, the step that turned Boole's ideas into hardware.
In his master's thesis, Shannon showed that circuits of relays and switches can carry out Boole's algebra, and so can add binary numbers. It was published in 1938.
Why it mattered. It is the idea behind every logic gate and adder in a calculator chip.
The British engineer Alec Reeves, working for an ITT company in France, invented pulse-code modulation: measuring a sound wave thousands of times a second and sending each measurement as a number. It was too early for the electronics of the day.
Why it mattered. Every digital phone call, and much of today's audio, still uses his idea.
Ardeshir Irani and director Moti GidwaniBombay, India
Kisan Kanya told the story of poor farmers. Irani bought the rights to an American process called Cinecolor, and the film was made and processed in India. It is described as India's first indigenously made colour film.
Why it mattered. Indian cinema began its long love affair with colour at home, not abroad.
After Fleischer's patent ran out, Disney animators filmed live actors and used rotoscoping as reference for Snow White and the Prince, to make their movement look human.
Why it mattered. It showed that audiences read real human motion as more believable, a big reason mocap exists.
William Garity and Disney’s camera departmentBurbank, California
Disney’s vertical multiplane camera held up to seven levels of art on glass, with the camera above. Levels moved by different amounts to fake depth. It was first used on the short The Old Mill, which won an Oscar. Reiniger (1920s) and Ub Iwerks (1933) had built earlier versions.
Why it mattered. Parallax between layers gave flat drawings real depth, a trick every 2D program now copies.
Walt Disney ProductionsCarthay Circle Theatre, Los Angeles
Snow White and the Seven Dwarfs was the first cel-animated feature film. It cost about $1.5 million, a huge sum then, and used live-action reference, model sheets and the multiplane camera. Disney won an honorary Oscar: one statuette and seven small ones.
Why it mattered. It proved a drawn film could hold an audience for 80 minutes and make people cry.
For the film Khwab Ki Duniya, Babubhai Mistry made objects seem to move on their own by using black threads that the camera could not see. People nicknamed him Kala Dhaga, meaning black thread. He went on to direct mythological films full of trick photography.
Why it mattered. He is remembered as Indian cinema's first credited trick photographer.
Arnold & Richter (ARRI), engineer Erich KästnerMunich, Germany
ARRI's Arriflex 35 had a spinning mirror in front of the film. While the shutter was closed, the mirror bounced the image to the viewfinder, so the operator saw exactly what the lens saw. It was light enough to carry, and it became the first reflex 35 mm production movie camera.
Why it mattered. Seeing through the taking lens made framing and focus exact, and every serious cine camera since has done it.
Tenggren, a Swedish book illustrator, worked at Disney from 1936 to 1939. His paintings of forests, cottages and villages helped set the European fairy-tale look of Snow White and the Seven Dwarfs (1937) and Pinocchio (1940). Layout artists used them as guides.
Why it mattered. A few paintings could steer the look of a whole film made by hundreds of people.
Using the new cathode-ray oscilloscope, Erlanger and Gasser showed that a nerve holds fibres of different widths, and that thicker fibres carry signals faster. They won the 1944 Nobel Prize.
Why it mattered. Their A, B and C fibre classes are still used today.
Foley designed a soft tube with a small balloon near its tip that is filled inside the bladder to hold it in place. C. R. Bard made it and named it after him.
Why it mattered. It is still the standard way to drain a bladder in hospital.
Fantus opened a store of donated, citrated blood that could be "deposited" and "withdrawn", and coined the name blood bank. Earlier blood services had run in Moscow and Barcelona. In its first year it supplied over 1,300 transfusions.
Why it mattered. Hospitals everywhere copied the idea.
Unsmelled natural gas leaked and built up under a school, and a spark set it off. Around 300 people, most of them children, were killed. Texas then passed a law requiring gas to carry a strong smell, a “malodorant”, and other places followed. Today mercaptans such as ethyl mercaptan, added to LPG, do this job.
Why it mattered. The smell of a gas leak is a safety feature, added so that noses can raise the alarm.
Wilder Penfield and Edwin BoldreyMontreal Neurological Institute, Canada
During epilepsy surgery on awake patients, Penfield gently stimulated the cortex with electricity and asked what they felt. He mapped the body along the motor and touch strips, later drawn as the homunculus.
Why it mattered. His maps showed the crossed, distorted body plan in the cortex, with huge hands and lips.
Fred Osius and Fred WaringChicago and New York, USA
Fred Osius, the Hamilton Beach founder, designed a better blender, and the bandleader Fred Waring put $25,000 into it. The ‘Miracle Mixer’ was shown at the National Restaurant Show in Chicago for $29.75, and in 1938 it was renamed the Waring Blendor. Also in 1937, W. G. Barnard's company, later Vitamix, began selling its own blender.
Why it mattered. The blender became a famous kitchen machine, and its jar-and-blade design spread around the world.
Bendix Home Appliances; John W. Chamberlin and Rex E. Bassett Jr.South Bend, Indiana, USA
The Bendix Home Laundry was a front-loader with a glass porthole door, a rotating drum and an electric timer that ran the wash, rinse and spin by itself. Its inventors found that at just the right speed the drum lifts clothes and lets them fall back through the water. It had no springs to soak up shaking, so it had to be bolted to the floor to stop it 'walking'.
Why it mattered. For the first time you could load the clothes, set the machine going and walk away.
Crompton Parkinson Works (later Crompton Greaves)India
A British firm set up Crompton Parkinson Works in India in 1937, and it came under Indian ownership in 1947. By the 1940s Crompton Greaves had become the largest ceiling fan maker in the world.
Why it mattered. India, the land of the punkah, became a giant of the electric ceiling fan.
Chester Carlson and Otto KorneiAstoria, New York, USA
Carlson and Kornei rubbed a sulfur-coated zinc plate to charge it, shone light through a glass slide reading "10-22-38 Astoria", then dusted it with powder. The powder stuck where the light hadn't reached. Carlson called the process electrophotography.
Why it mattered. Charge, light and powder is exactly how every laser printer works today.
Heymans and his father ran tricky experiments on dogs, keeping a head alive on blood from a second dog. They found that small sensors near the big arteries in the neck, above all the carotid bodies, check the blood and send signals that change breathing. Heymans won the 1938 Nobel Prize, handed over in 1939.
Why it mattered. The carotid bodies are the body's main alarm for low oxygen in the blood.
Heymans, building on Heinrich Hering's work, showed with dogs that sensors in the carotid artery and aorta detect blood pressure and blood chemistry and adjust breathing and circulation through reflexes. His Nobel Prize citation names breathing.
Why it mattered. These baroreceptors are why you do not faint every time you stand up.
Sturtevant, licensed to make a beam-type torque wrench designed at Chrysler, patented his own and became the first person to sell torque wrenches. Car makers began printing a torque for every important bolt.
Why it mattered. Tightening torque became part of every workshop manual.
High up, the air is too thin to breathe comfortably. The Stratoliner pumped extra air into a sealed cabin, so at 16,000 feet the passengers felt as if they were at 8,000 feet. It entered airline service in 1940, flying above much of the bad weather.
Why it mattered. Pressurised cabins made high, smooth, long-distance flying normal.
Roy J. Plunkett and Jack RebokDuPont Jackson Laboratory, New Jersey, USA
Looking for a new refrigerant gas, Plunkett opened a cylinder that should have been full, but nothing came out. Inside was a waxy white solid: the gas had joined up into polytetrafluoroethylene, PTFE. DuPont sold it as Teflon from 1945.
Why it mattered. PTFE has one of the lowest friction coefficients of any solid, about 0.04.
At Columbia University, Rabi sent a beam of molecules through magnets and a radio-frequency field. At one exact frequency the nuclei flipped and the beam went astray: magnetic resonance. It won him the 1944 Nobel Prize in Physics.
Why it mattered. It proved nuclei can be flipped by radio waves at a frequency set by the field.
Working separately, Simmons and Ruge found that a fine wire glued to a surface changes its electrical resistance when the surface stretches by a tiny amount. They shared the patent, and the gauge was sold as the SR-4. Glue gauges onto a sturdy block of metal and you get a load cell, which turns force into an electrical signal.
Why it mattered. Load cells built on strain gauges are inside most digital scales, cranes and test machines today.
László Bíró, a journalist, noticed that newspaper ink dried fast without smudging, but was too thick for a fountain pen. With his brother György, a chemist, he paired thick, quick-drying ink with a ball in a socket and patented it in Britain.
Why it mattered. The right ink made the rolling ball practical. In many countries a ballpoint is still called a “biro”.
In Stagecoach, stuntman Yakima Canutt dropped from a moving coach, passed beneath the horses and climbed back on. He also invented safety gear for stunt riders, such as special stirrups and cable systems for controlled falls.
Why it mattered. Canutt showed that great stunts are planned and engineered, not just brave.
A. Arnold Gillespie, MGMMGM studios, Culver City, California
For The Wizard of Oz, Gillespie's team tried a rubber cone first, but it was too stiff. The final twister was a long muslin sock, about 35 feet according to accounts, hung from a moving crane and twisted as it moved. Dust and wind machines finished the effect.
Why it mattered. A simple piece of fabric became one of the most convincing storms in film history.
William Cameron MenziesCulver City, California, USA
Producer David O. Selznick gave Menzies a new title for Gone with the Wind: production designer. It meant he had the final word on how the whole film looked. He won a special Oscar for using colour to set the mood.
Why it mattered. The job of designing a film's whole look before filming now had a name and a credit.
William Cameron Menzies, for David O. SelznickCulver City, California, USA
Gone with the Wind was one of the first live-action films to be storyboarded from start to finish. Menzies designed the shots, and the title production designer was coined for him, meaning he had the final word on how the film looked. He won an honorary Oscar for his use of colour.
Why it mattered. It proved that big live-action films could be planned in pictures, just like cartoons.
Küntscher pushed a long metal nail down the hollow centre of a broken thigh bone to hold the pieces in line from inside. When he showed 12 cases in 1940, many surgeons disapproved. Today these nails are a standard way to fix a broken femur, and patients can walk far sooner.
Why it mattered. It fixed bones from the inside, using the marrow cavity as a channel.
At the 1939 New York World's Fair, four Novachords played every day at the Ford stand. Inside, 163 vacuum tubes made bright tones, and filters shaped them into softer sounds, with every key able to play at once. Only 1,069 were built before wartime shortages stopped production.
Why it mattered. It is often called the first commercial polyphonic synthesizer, and it already used the start-bright-then-filter recipe of later synths.
Frank Philip Bowden and T. P. HughesCambridge, England, and the Swiss Alps
Sliding objects over ice and snow at different speeds and temperatures, Bowden and Hughes argued that frictional heating melts a thin layer of water under a sliding ski or skate.
Why it mattered. It explained gliding on very cold ice, where pressure melting can't.
Earl Thompson and a General Motors teamMichigan, USA
General Motors engineers built the Hydra-Matic, which used oil in a fluid coupling and three sets of planetary gears to pick among four forward speeds on its own. Oldsmobile offered it in 1939 on its 1940 cars.
Why it mattered. It was the first mass-produced fully automatic transmission for passenger cars.
Ralph Fowler, with Edward GuggenheimCambridge, England
If A is as warm as B, and B is as warm as C, then A is as warm as C. This is why thermometers work, but nobody had called it a law. Fowler did in the 1930s, and it appeared in his 1939 book with Guggenheim. The other laws already had numbers, so it became the zeroth law.
Why it mattered. It made the idea of temperature itself part of the rules.
Larry Butler and team, for The Thief of BagdadEngland and Hollywood, USA
Butler filmed actors in front of a bright blue screen, then used the blue to make mattes that cut them out cleanly. A genie escaping from a bottle was one of the scenes. The film, starring Sabu, a teenager from Mysore, won the Oscar for special effects.
Why it mattered. It was the first proper bluescreen travelling matte, the ancestor of every green screen in the world.
Walt Disney Studios and RCABroadway Theatre, New York, USA
Fantasia premiered with Fantasound, the first commercial film released in stereo, with speakers around the hall and music that could move between them. It needed so much equipment that only a handful of theatres could play it.
Why it mattered. It was the first try at surround sound, and it gave mixing the pan pot for moving sounds.
Fred Sersen; E. H. HansenAmbassador Hotel, Los Angeles
At the 12th Academy Awards, honouring films of 1939, the Academy gave its first competitive award for Special Effects. It went to The Rains Came, a film with a huge earthquake and flood.
Why it mattered. Effects work was now officially recognised as its own art.
Crime films such as Stranger on the Third Floor (1940) and The Maltese Falcon (1941) used low-key lighting: a strong key light, little fill, and deep, hard shadows. The look borrowed from German Expressionist cinema. In 1946 a French critic, Nino Frank, called these films film noir, or black film.
Why it mattered. Noir showed that what you leave dark can tell the story as much as what you light.
Danish illustrator Kay Nielsen worked at Disney from 1937 to 1941. His art was used for the Night on Bald Mountain and Ave Maria part of Fantasia (1940). He also painted ideas for a Little Mermaid film that was only made in 1989.
Why it mattered. Concept art can wait for decades and still shape a film.
Janet Vaughan and Charles DrewLondon, England and New York, USA
In London, the haematologist Janet Vaughan planned depots that stored donated blood for air-raid victims. In New York, the surgeon Charles Drew ran the Blood for Britain project, which shipped over 5,000 litres of plasma, and then led the first American Red Cross blood bank.
Why it mattered. Their work turned blood donation into a national service.
Lionel Fielden, Controller of Broadcasting, after a campaign by John FouldsDelhi, India
The composer John Foulds, who ran Western music at All India Radio, wrote in 1938 that the harmonium's tuning did not fit Indian music. Soon after, the radio banned it from its Indian music programmes, and the ban took effect on 1 March 1940. Protesting musicians staged a mock funeral and buried eleven harmoniums.
Why it mattered. For three decades, India's national radio refused to play its most popular accompanying instrument.
Pannalal Ghosh, born in Barisal in 1911, took the simple folk bansuri and redesigned it for classical ragas. He made it much longer, about 32 inches, for a deep, rich tone, and added a seventh hole to reach an extra note in the low octave. Before him the bansuri was mostly a folk instrument in Hindustani music.
Why it mattered. He is widely called the father of the modern classical bansuri.
Hollow electric guitars howled with feedback when played loud. Les Paul built the Log from a solid 4-by-4-inch length of Douglas fir, with a bridge and a pickup on top. A solid body barely vibrates, so the sound comes from the strings and pickup alone.
Why it mattered. It showed that an electric guitar did not need a hollow body at all.
Four months after opening, the 853 m span twisted about 12 times a minute in a steady 64 km/h wind, until it tore apart and fell into Puget Sound. Film of the collapse became world famous.
Why it mattered. Often called resonance, it was really aeroelastic flutter: the twisting deck made the wind push it harder, and bridges have been wind-tested ever since.
John Randall and Harry BootPoynting Physics Building, University of Birmingham, England
Randall and Boot drilled holes around a solid copper block so it rang with microwaves, a bit like blowing across a bottle. When they switched it on, it made about 400 W at a wavelength of about 10 cm, around a hundred times more than earlier tubes at that wavelength. Within weeks, engineers pushed it past 1 kW.
Why it mattered. Every microwave oven's magnetron is a descendant of this copper block.
The Tizard Mission, with Edward ‘Taffy’ BowenWashington and New York, USA
Britain sent a team of scientists to share its war secrets with the United States. The Welsh physicist Bowen carried cavity magnetron number 12 in a box. On 19 September it was shown working to astonished American scientists, whose best tubes made far less power at those wavelengths.
Why it mattered. An American historian later called it “the most valuable cargo ever brought to our shores”.
MIT Radiation Laboratory and Bell LabsCambridge, Massachusetts, USA
Within weeks of the demonstration, the Radiation Laboratory opened at MIT to build microwave radar around the magnetron. Bell Telephone made its first 30 magnetrons that October. By the end of the war, almost every Allied radar used one.
Why it mattered. Thousands of scientists and engineers learned to work with microwaves, and some later brought that knowledge to the kitchen.
On an Antarctic expedition, Siple and Passel timed how fast a small bottle of water froze in different winds. Their results gave the first wind chill formulas: moving air strips away the warm layer around your skin.
Why it mattered. It explains why a fan cools people, not rooms: the air is no colder, it just takes heat from you faster.
Toland wanted faces near the camera and people far away to be sharp at once. That needs a small aperture, f/8 to f/16 instead of the usual f/2.3 to f/3.5, and so a lot more light. He used powerful carbon arcs, Kodak Super-XX film rated at ASA 100, and coated lenses that let more light through.
Why it mattered. It showed how light, film speed and aperture are traded against each other to shape a picture.
Dayton C. MillerLibrary of Congress, Washington, D.C.
Dayton C. Miller was an American physicist who studied sound and played the flute. He collected nearly 1,700 flutes and other wind instruments, including about 40 from the Munich workshops of Boehm and his successors, and they reached the Library of Congress in 1941. He also translated Boehm's book on the flute into English.
Why it mattered. His collection lets anyone study how the flute changed across centuries and continents.
Tau Moe, a Samoan-born musician raised in Hawaii, first toured India in the late 1920s. He lived in Calcutta from 1941 to 1947, where his family performed, taught Hawaiian guitar and built steel guitars. By the 1960s the steel guitar was common in Indian popular and film music.
Why it mattered. The Hawaiian slide guitar took root in India and grew into a new classical instrument.
When cheap natural gas arrived in southern California, solar sales there fell, but Florida took up the idea. By 1941 one Florida company had installed more than 60,000 heaters, and over half the people of Miami heated their water with the sun.
Why it mattered. It proved solar hot water could work for a whole city, until cheap electricity pushed it aside.
While held in prison during the Quit India movement, Gandhi wrote short chapters on the body, food, air, water, earth, sun and akash (space), and on self-control. Navajivan published the book in October 1948.
Why it mattered. It set out nature cure in plain words for millions of Indian readers.
Film star Hedy Lamarr and composer George Antheil patented a way to stop radio-guided torpedoes being jammed: the sender and receiver hop between frequencies in the same secret order. The navy shelved it at the time.
Why it mattered. Frequency hopping and spread-spectrum ideas later helped make crowded digital radio, including some phone systems, Bluetooth and Wi-Fi, work.
Albert Szent-Györgyi, Brunó Straub and Ilona BangaSzeged
In wartime Szeged, Straub purified a second protein, actin. Szent-Györgyi's team mixed it with myosin to make "actomyosin" threads, added ATP, and watched the threads shrink. Szent-Györgyi called it seeing motion, the oldest sign of life, in a test tube.
Why it mattered. Muscle contraction became chemistry you could do on a bench.
All India Institute of Hygiene and Public HealthKolkata (Calcutta), India
India's first blood bank opened in Kolkata in 1942, at first to meet wartime needs and run with the Red Cross. In 1945 it moved to Calcutta Medical College as the country's first civilian blood bank.
Why it mattered. It was the start of India's blood transfusion services.
In his history of the psychology of the senses, Boring redrew Hänig's 1901 results as a graph of how sensitive each part of the tongue edge was, with no numbers on the scale. Readers took the peaks to mean each taste lived in only one area, and a tongue map spread into textbooks.
Why it mattered. It shows how a small misreading can travel for decades.
Harley-Davidson, BMW, Royal Enfield and othersUSA, Germany, Britain
Harley-Davidson built about 56,000 WLA motorcycles for the Allies during the war, plus about 20,000 WLC models for Canada. Germany used BMW and Zündapp sidecar outfits. Royal Enfield's light 125 cc 'Flying Flea' was dropped by parachute with airborne troops.
Why it mattered. After the war, many soldiers came home knowing how to ride, and cheap ex-army bikes helped start a motorcycle boom.
Warren McCulloch and Walter PittsChicago, United States
A brain scientist and a young self-taught logician wrote a paper describing a very simple "neuron" on paper. It adds up its inputs and fires only if the total crosses a threshold. They showed that networks of these units could, in principle, work out logic.
Why it mattered. It was the first artificial neuron, a loose and simplified sketch inspired by real brain cells, not a copy of them.
Ray started work at the advertising agency D.J. Keymer as a junior visualiser. He also illustrated a children's edition of the novel Pather Panchali. That book later became his first film.
Why it mattered. His training as a commercial artist shaped how he planned films in pictures.
During the German occupation, the Dutch doctor Willem Kolff wound cellophane sausage casing around a rotating drum in a bath of salt solution. Blood ran through the casing, and waste like urea diffused out while blood cells and proteins stayed in. In 1945 a patient in kidney failure survived thanks to it.
Why it mattered. Dialysis by diffusion now keeps millions of people with failed kidneys alive.
Percy Spencer and RaytheonWaltham and Newton, Massachusetts, USA
Carving each magnetron from solid copper was slow. Spencer, Raytheon's self-taught chief engineer, found a way to stamp out thin copper pieces and join them, and output rose to about 2,600 a day. By 1945 Raytheon had built about 80% of all the magnetrons made.
Why it mattered. Mass production made magnetrons cheap and familiar, the first step toward one in every home.
Fleeing the war in Europe, the brothers settled in Argentina, filed a new patent and began making “Birome” pens. Argentina celebrates Inventor's Day on 29 September, László Bíró's birthday.
Why it mattered. The ballpoint's first commercial home was in South America.
Tommy Flowers and the Bletchley Park codebreakersDollis Hill and Bletchley Park
During the Second World War, engineer Tommy Flowers built Colossus to help crack the German Lorenz cipher. It used about 1,600 vacuum tubes in its first version and was working by early 1944. It was kept secret for decades.
Why it mattered. It is often called the first programmable, electronic, digital computer, though it was built for one kind of job.
An optical printer is a projector pointing into a camera, so one strip of film can be copied onto another, layer by layer. Dunn had used his printers on King Kong (1933) and Citizen Kane (1941). The Acme-Dunn model, built for the US military, earned an Academy technical award in 1944.
Why it mattered. For fifty years, almost every effects shot was put together, or composited, on a machine like this.
Albert Schatz, Elizabeth Bugie and Selman WaksmanRutgers University, New Jersey, USA
In 1943 a student, Albert Schatz, working in Waksman's lab, found a soil microbe that made a new drug, streptomycin. It could kill the TB germ. In November 1944 it was first given to a very sick young woman with TB in Minnesota, and she recovered.
Why it mattered. For the first time, TB of the lungs could be cured with medicine instead of just rest and fresh air.
Helen Taussig, Alfred Blalock and Vivien ThomasJohns Hopkins Hospital, Baltimore, USA
Paediatric cardiologist Helen Taussig saw that some babies turned blue because too little blood reached their lungs. Surgeon Alfred Blalock and his lab technician Vivien Thomas worked out an operation to join an artery to the lung artery, and Thomas guided Blalock through the first one. The little girl, Eileen Saxon, turned pink.
Why it mattered. It was one of the first operations to fix a heart problem, and it saved thousands of children.
Gandhi became founder-trustee and chairman for life of the All India Nature Cure Foundation Trust, signing a deed to make nature cure available to all, especially the poor.
Why it mattered. India's Naturopathy Day is held on this date.
J. Presper Eckert and John MauchlyUniversity of Pennsylvania, Philadelphia
ENIAC filled a large room: about 18,000 vacuum tubes, 30 tons and 150 kilowatts of power. It could do about 5,000 additions a second, far faster than anything before it. It was finished in 1945 and shown to the public in February 1946.
Why it mattered. It proved that a big, general-purpose electronic computer could really work.
John von Neumann, with the ENIAC teamMoore School, Philadelphia
John von Neumann wrote the 'First Draft of a Report on the EDVAC'. It described a computer that keeps its program in the same memory as its data, so a new program can be loaded as easily as new numbers. Eckert and Mauchly had worked on these ideas too, and the credit is still argued about.
Why it mattered. Almost every computer since has kept its program in memory this way.
During the Second World War, Kolff built a dialysis machine from sausage casing wound round a rotating drum in a bath of fluid, using parts such as orange-juice cans and car parts. His first patients died, but in 1945 a 67-year-old woman survived.
Why it mattered. It was the first dialysis machine to save a life, and the start of modern dialysis.
Sister Rosetta Tharpe sang gospel while playing driving electric guitar, and was a star from the late 1930s. Her 1945 record "Strange Things Happening Every Day" reached No. 2 on the Billboard race records chart and is called by some the first rock and roll record. Elvis Presley, Chuck Berry and Little Richard all learned from her.
Why it mattered. The Rock & Roll Hall of Fame calls her the first guitar heroine of rock and roll.
Maxson, a former US Navy officer, built the Whirlwind oven to heat frozen meals on aircraft. A small motor blew hot air around plates stacked one above another, so every meal warmed evenly. It was the first convection oven in wide use, and Pan Am served his frozen Sky Plates to passengers.
Why it mattered. Blowing hot air around food cooks it faster and more evenly, the basic idea of every air fryer.
Working on radar magnetrons, Spencer noticed a chocolate bar in his pocket had melted. He tried popcorn and an egg next, and Raytheon patented microwave cooking in 1945.
Why it mattered. It led to the microwave oven, whose 12 cm standing waves this box lets you watch.
The famous story says Spencer was standing near a working radar magnetron when a candy bar in his pocket melted. No reliable first-hand record of it exists. He then tried popcorn kernels, which popped, and an egg, which exploded, reportedly in a colleague's face.
Why it mattered. Whatever really happened, Spencer saw that microwaves could cook, and Raytheon decided to sell ovens.
Raytheon filed Spencer's patent, ‘Method of Treating Foodstuffs’, for cooking with waves about 10 cm long. It said an egg could be hard-boiled with about 2 kilowatt-seconds of energy, compared with 36 on a normal stove. It was granted in 1950 as US patent 2,495,429.
Why it mattered. It described cooking with microwaves from a magnetron, the idea inside every microwave oven.
Ferdinand Porsche's team, Volkswagen, Major Ivan HirstWolfsburg, Germany
The Beetle was designed in the 1930s as a cheap ‘people's car’, but war stopped production. From 1945 a British officer, Major Ivan Hirst, helped restart the factory. The Beetle was later built in about twenty countries, and the last one rolled out in Puebla, Mexico, on 30 July 2003.
Why it mattered. With 21,529,464 built, it is the best-selling car ever made on a single design.
Ralph Odor, O. A. Sutton and designer Richard Ten EyckWichita, Kansas, USA
Odor had experimented with aircraft propellers before teaming up with Sutton. Their Vornadofan used sharply pitched blades inside a short duct to push a tight spiral of air that kept the whole room circulating.
Why it mattered. It showed that blade shape and a duct could make a fan move air much further.
Royal Air Force (Miles-Martin Pen Company)United Kingdom
The British government licensed Bíró's design so RAF aircrew could write in unpressurised planes, where fountain pens leaked as the air pressure dropped.
Why it mattered. A war-time need proved the ballpoint was tougher than the fountain pen.
American businessman Milton Reynolds rushed out a ballpoint and sold it at Gimbels department store for $12.50, a lot of money at the time. Crowds queued and thousands sold on the first day, though many early pens leaked or skipped.
Why it mattered. It showed the enormous demand for a pen you never had to dip or fill.
M. K. Gandhi, later Manibhai DesaiUrulikanchan, near Pune
Gandhi came to the village of Urulikanchan and set up a nature cure centre for rural people, with village sanitation, clean water, diet, mud and water treatments. Local people gave land for the trust.
Why it mattered. The Nisargopchar Ashram still treats thousands of patients a year.
Health Survey and Development Committee, chaired by Joseph BhoreDelhi
The Bhore Committee proposed that every Indian should get health care regardless of ability to pay, through a network of primary health centres linked to bigger hospitals, and that a national medical institute should train doctors and do research.
Why it mattered. It shaped India’s ladder of sub-centres, PHCs and district hospitals, and led to AIIMS.
Kay McNulty, Betty Jennings, Betty Snyder, Marlyn Wescoff, Fran Bilas, Ruth LichtermanUniversity of Pennsylvania, Philadelphia
ENIAC had no keyboard and no programming language. Six women worked out how to program it by setting switches and plugging cables, often from wiring diagrams alone. At the 1946 unveiling they were barely mentioned.
Why it mattered. They were among the first programmers, and their story was left out of most histories for decades.
The Mobile Telephone Service let drivers make calls from a heavy radio set in the boot. One big transmitter covered the whole city, so only a few calls could happen at once, and an operator connected every one.
Why it mattered. It showed the demand, and the limit: one tower for a whole city could never serve many people.
Franz GreiterAustria (named after Piz Buin, a peak in the Alps)
After a bad sunburn while climbing the mountain Piz Buin in 1938, chemistry student Franz Greiter set out to make a better sun cream. In 1946 he launched Gletscher Crème (glacier cream), often called the first modern sunscreen, with an estimated SPF of only about 2. In 1974 he introduced the sun protection factor, the SPF number on bottles today.
Why it mattered. It gave people a way to shield their skin from UV and a number to compare one cream with another.
Enrico Piaggio and Corradino D'AscanioPontedera, Italy
Aircraft engineer D'Ascanio designed a scooter for a country with broken roads and little money: a step-through body that kept your clothes clean, a small engine beside the back wheel and a spare tyre. Vespa means 'wasp' in Italian.
Why it mattered. It turned powered two-wheelers into everyday transport for ordinary families.
Edward Purcell and Felix BlochCambridge, Massachusetts and Stanford, USA
Two teams, working separately, found the signal in everyday materials. Purcell's group at Harvard saw it in paraffin wax on 15 December 1945, and Bloch's group at Stanford saw it in water in January 1946. They shared the 1952 Nobel Prize in Physics.
Why it mattered. For the first time the hydrogen in a lump of matter, or a body, could be made to give a radio signal.
David Byerly and Procter & GambleCincinnati, Ohio, USA
Procter & Gamble launched Tide in test markets, the first heavy-duty synthetic detergent. Chemist David Byerly had kept working on it quietly after the project was nearly dropped, and found that adding a lot of a 'builder' called sodium tripolyphosphate made it clean far better. By 1949 it was sold across the United States.
Why it mattered. Unlike soap, it did not leave scum in hard water, and it cleaned well in the new automatic machines.
John Bardeen, Walter Brattain and William ShockleyBell Labs, Murray Hill, New Jersey
At Bell Labs, Bardeen and Brattain made a tiny switch and amplifier from a piece of germanium. Shockley soon designed a better version. The three shared the 1956 Nobel Prize in Physics.
Why it mattered. Transistors replaced hot, fragile vacuum tubes and are the switches inside every chip today.
Douglas H. Ring and W. Rae Young, Bell LabsNew Jersey, USA
In an internal memo, Bell Labs engineers proposed covering an area with many small low-power cells, each reusing the same channels as cells far enough away, and hexagons were used to draw them. The electronics to switch calls between cells did not exist yet.
Why it mattered. Frequency reuse in small cells is still how every mobile network works.
During surgery on a 14-year-old boy, his heart began to quiver instead of beat. Beck's team massaged it by hand, then shocked it directly with electrodes. A normal rhythm came back and the boy recovered.
Why it mattered. It was the first time a human heart was saved with defibrillation.
A Milan steel-tube company launched the Lambretta scooter, the Vespa's great rival. Both were later built under licence around the world, India included.
Why it mattered. Two Italian scooters set the pattern for millions of scooters in Asia.
John L. Barker Sr. and Ben MidlockGlastonbury, Connecticut, USA
Two engineers at the Automatic Signal Company turned wartime Doppler radar into a speed meter. Connecticut State Police tried it in 1947 and began issuing radar speeding tickets in February 1949.
Why it mattered. The Doppler shift of a reflected wave measures speed directly, with no stopwatch.
US factories had stopped making washers during the Second World War, but engineers kept designing. In 1947 General Electric introduced its first top-loading automatic model, and many other makers followed in the late 1940s and early 1950s.
Why it mattered. The automatic top-loader became the standard American washing machine for decades.
John Bardeen, Walter Brattain and William ShockleyBell Labs, Murray Hill, New Jersey, USA
Bardeen and Brattain made a tiny crystal device that could amplify a signal, and showed it to their bosses on 23 December 1947. Shockley soon designed an improved version. The three shared the 1956 Nobel Prize in Physics.
Why it mattered. A switch with no moving parts made possible every electronic inverter that followed.
The US FCC and the International Telecommunication UnionWashington, and Atlantic City, New Jersey, USA
On 30 December 1946 the US Federal Communications Commission approved 2,450 MHz for microwave cooking. In 1947 an international radio conference in Atlantic City set aside bands for industrial, scientific and medical use, and the American delegation proposed 2.4 GHz for microwave heating. Kitchen ovens still use 2.45 GHz, with waves about 12 cm long.
Why it mattered. Ovens got their own slice of the radio spectrum, which Wi-Fi and Bluetooth now share.
The first microwave oven for sale was almost 1.8 m tall and weighed about 340 kg. It used 3 kW of power, about three times a modern oven, and its magnetron was cooled with water. It cost about $5,000, and went to restaurants, ships and railway dining cars. Its name won a Raytheon staff contest.
Why it mattered. It proved microwave cooking worked, even if no family could fit or afford one.
After the Second World War, cheaper and smaller window units arrived, and more than 43,000 were sold by 1947. Air conditioning helped people and factories move to the hot, sunny American South and West, the Sun Belt.
Why it mattered. Cooling changed where people could comfortably live and work.
Chuck Yeager, Bell X-1Muroc Army Air Field, California
The rocket-powered Bell X-1 flew level faster than the speed of sound. Near that speed air squashes and shock waves form, so the simple, incompressible Bernoulli equation no longer holds.
Why it mattered. High-speed flight needed the compressible version of the law.
Medical Research Council, with Austin Bradford HillLondon
Streptomycin was new and scarce, so the MRC tested it fairly. 107 patients with tuberculosis were allocated by random numbers in sealed envelopes to streptomycin plus bed rest or bed rest alone. After six months, 7% of the streptomycin group had died, against 27% of the others.
Why it mattered. Its design, random allocation that nobody could predict, became the gold standard for testing treatments.
Claude ShannonBell Labs, Murray Hill, United States
In the paper that founded information theory, Shannon generated text by picking each letter or word according to how often it followed the previous ones. With longer contexts, the nonsense looked more and more like English.
Why it mattered. It is exactly the idea in chapter 1: a model that predicts the next piece from counts.
Frederic Williams, Tom Kilburn and Geoff TootillUniversity of Manchester
A small test machine nicknamed the Baby ran its first program on 21 June 1948. The program, which found the largest factor of a number, sat in the machine's own electronic memory, a special cathode ray tube.
Why it mattered. It was the first computer to run a program stored in its own electronic memory.
The Curta, a hand-cranked mechanical calculator small enough to hold in one hand, went on sale. Herzstark had worked out its design while a prisoner in the Buchenwald concentration camp.
Why it mattered. It was the best pocket calculator in the world until electronic ones arrived in the early 1970s.
The German Magnetophon tape recorder, first shown in 1935 and greatly improved by high-frequency bias in the early 1940s, was brought to the USA after 1945. Ampex built its own machines by 1948, and studios soon recorded and edited film sound on magnetic tape and film.
Why it mattered. Tape could be cut, copied and re-recorded without losing quality, which made complex sound editing possible.
A BCG vaccine laboratory was set up at the King Institute in Guindy, and vaccination against tuberculosis began in August 1948. BCG, a weakened cousin of the TB germ, is still given to Indian babies at birth.
Why it mattered. It began one of the world’s largest vaccination efforts.
Philip Hench, Edward Kendall and Tadeus ReichsteinMayo Clinic, Rochester, USA
A young woman with painful rheumatoid arthritis could hardly get out of bed. Doctors injected her with compound E, an adrenal hormone Kendall had purified, now called cortisone. Within about a week she said she had never felt better in her life. Hench, Kendall and Reichstein won the Nobel Prize in 1950.
Why it mattered. It showed how strong adrenal hormones are, and steroid medicines have been used ever since.
9th General Conference on Weights and MeasuresParis, France
The conference adopted the name newton, symbol N, for the unit of force in the metre-kilogram-second system. One newton speeds up one kilogram by one metre per second, every second. In 1960 the 11th conference made it part of the new International System of Units, the SI.
Why it mattered. Every force in science and engineering is now measured in the same unit, all over the world.
The Bruneri brothers built an excavator whose arm and bucket were moved by oil-filled rams. In 1954 they sold the rights to the French firm SICAM, whose Yumbo diggers spread the idea.
Why it mattered. Hydraulic rams replaced cables and made the modern excavator, loader and backhoe.
9th General Conference on Weights and MeasuresSèvres, near Paris
The world's measurement conference gave the unit of force the name 'newton', symbol N. One newton speeds up a 1 kg mass by 1 metre per second, every second.
Why it mattered. Every force in science and engineering is now measured in newtons.
Land's three-year-old daughter asked why she couldn't see a photo straight away. The Polaroid Land Camera Model 95 answered her: a print developed inside the camera in about a minute.
Why it mattered. Instant results shaped how people expect photos to work, long before screens.
Vakil published a trial of Rauvolfia serpentina for high blood pressure in the British Heart Journal. Its compound reserpine became a worldwide blood-pressure medicine in the 1950s.
Why it mattered. Plants from traditional medicine can prove themselves in fair tests.
The cardiologist R. J. Vakil published a study of 50 patients with high blood pressure given Rauwolfia tablets for four weeks in the British Heart Journal. Most had a clear fall in blood pressure.
Why it mattered. Often called the first clinical trial from India, it caught the world’s attention.
Psychologist Donald Hebb published The Organization of Behavior. He suggested that when one brain cell keeps helping another to fire, the link between them grows stronger. That is one idea of how learning could live in connections.
Why it mattered. It gave neural networks their big idea about learning: change the strength of the connections.
Al Gross, who had already built walkie-talkies, turned his two-way radios into one-way receivers that could signal a person from a telephone. He aimed it at doctors, who at first worried the beeping would upset patients.
Why it mattered. It set the pattern for every pager since: a pocket receiver that is called, not a phone that calls.
3M's Scotchlite, a sheet covered in tiny glass beads, reflects light straight back towards its source. Shortly after it was invented, people began to experiment with projecting scenery onto it from the camera side.
Why it mattered. It led to front projection, which was much brighter than rear projection.
Alton, a Hungarian-born cinematographer who had worked in Argentina, lit noir films such as T-Men (1947) with pools of light in darkness. In 1949 he published Painting with Light, a book that explained film lighting to ordinary readers. In 1951 he shared an Oscar for the colour musical An American in Paris.
Why it mattered. Alton argued that lighting must create mood and meaning, not just make things visible.
The scholar Joseph Campbell compared myths from around the world and found one shared pattern, which he called the monomyth. A hero leaves the everyday world, faces trials and returns changed. George Lucas later used the idea for Star Wars.
Why it mattered. It gave storytellers a map of a journey that audiences everywhere seem to recognise.
India’s first neurology and neurosurgery department
Jacob ChandyVellore
Trained in Montreal under Wilder Penfield, Chandy returned to start the first department of neurology and neurosurgery in India, at the Christian Medical College. In 1958 he began India’s first training programme for neurosurgeons, whose students went on to found departments across the country.
Why it mattered. It began modern brain and spine surgery in India.
At a British burns unit, Bull and Squire found a way to measure progress: the burn size, as a share of the body's skin, at which half of patients die. For people aged 15 to 44 it was about 43% of the skin. Tracking this number for decades showed how much better burn care became.
Why it mattered. It turned “are we getting better at treating burns?” into a question with a clear answer.
Ridley noticed that splinters of acrylic plastic from aircraft canopies sat quietly in wounded RAF pilots' eyes. He designed an acrylic lens and implanted it after removing a cataract. Many doctors doubted him for years.
Why it mattered. Intraocular lenses are now fitted in millions of cataract operations every year.
In his book The Organization of Behavior, Hebb proposed that when one cell repeatedly helps fire another, the connection between them grows stronger. The phrase “cells that fire together wire together” came later as a summary.
Why it mattered. It gave a cell-level idea of how learning could work.
Jacob Chandy and B. RamamurthiVellore and Madras (Chennai), India
Jacob Chandy, trained under Penfield in Montreal, started India’s first neurology and neurosurgery department at Christian Medical College, Vellore, in 1949. In 1950 B. Ramamurthi set up the neurosurgery department in Madras. Both trained generations of Indian neurosurgeons.
Why it mattered. They built brain surgery in India almost from scratch.
In 1949 the young French flautist Jean-Pierre Rampal and his pianist hired a Paris concert hall for a whole evening of flute music, and it caused a sensation. Rampal went on to give about 120 concerts a year and make hundreds of recordings. He brought back forgotten Baroque music and inspired composers such as Poulenc to write new pieces.
Why it mattered. He turned the flute from an orchestra instrument into a solo star that filled concert halls.
After the Second World War, Hobart launched its first home dishwasher under the KitchenAid name. The KD-10 had a heavy cast-iron spray arm that spun beneath stainless-steel racks.
Why it mattered. Cochrane's line of machines finally reached ordinary American kitchens, just as the post-war building boom began.
Launderette on QueenswayQueensway, London, England
The first launderette in the United Kingdom opened on Queensway in London. In post-war Britain few homes had a washing machine, so launderettes spread quickly through towns and cities.
Why it mattered. Shared machines let millions of people stop washing by hand long before they could buy their own.
Earlier derailleurs existed, but Campagnolo's Gran Sport used a parallelogram that moved the chain cleanly between cogs, setting the pattern for the derailleurs on most bikes today.
Why it mattered. Many gears, shifted while riding.
Al Gross and New York's Jewish HospitalNew York City
New York City's Jewish Hospital began using Gross's paging system in 1950, one of the first practical paging services, for physicians who needed to be reached anywhere in the building.
Why it mattered. Hospitals became paging's first and most loyal customers.
Osram engineers built a lamp that sparks an arc through xenon gas inside a strong glass bulb. The first public projection with it was in Berlin in 1950, and Osram began selling cinema lamps in 1952. They reached the US in 1963 and became common in the 1970s.
Why it mattered. A xenon lamp gives steady white light for thousands of hours without anyone adjusting rods, and many digital projectors still use one.
Eastmancolor put all three colour layers on a single strip of negative film. Any normal camera could now shoot in colour, without Technicolor's giant three-strip camera. By the late 1950s it had pushed out the older system around the world, including in India.
Why it mattered. One colour negative meant the lab, not the camera, became the place where colour was fine-tuned.
To show films on television, a machine called a telecine turns each frame into a video signal. Cintel's flying spot telecine swept a bright dot of light across the film, and the first one was installed at the BBC in 1950. Later Rank Cintel machines became standard in post houses around the world.
Why it mattered. Telecine rooms were where colour correction for video was born.
For decades, most scenes of people talking in cars were shot on a stage. The actors sat in a car or a cut-down mock-up while a filmed road played on a screen behind them, and crew rocked the car to fake the bumps.
Why it mattered. Driving shots, or 'process shots', are still one of the biggest jobs for LED stages today.
Kodak's Eastmancolor negative put all three colour layers on one film that fitted an ordinary camera. The first stock was rated about 16 in daylight, and by 1952 a tungsten-balanced 25 ASA version followed. The bulky three-strip cameras were retired in the 1950s.
Why it mattered. Studios could now light colour films with cheaper tungsten lamps instead of carbon arcs.
Blair joined Disney in 1940 as a colour stylist and travelled to Latin America with Walt Disney in 1941. Her concept art set the style of Cinderella (1950), Alice in Wonderland (1951) and Peter Pan (1953). She used bright, unexpected colours in strong contrast.
Why it mattered. She showed that colour choices in concept art could give a film its whole feeling.
Willem-Karel DickeThe Hague and Utrecht, Netherlands
Dicke, a Dutch children's doctor, suspected wheat was harming children with coeliac disease. During the hunger winter of 1944 to 1945, when bread was scarce, some of his patients got better, and when bread returned they got worse, according to accounts of his work. In 1950 his thesis showed that removing wheat and some other grains cured the children.
Why it mattered. It gave the world the gluten-free diet.
At a time when stomach cancer was the leading cause of death in Japan, the surgeon Tatsuro Uji asked Olympus for a camera that could photograph the stomach from inside. With the engineer Mutsuo Sugiura they built the gastrocamera, a tiny camera and flash bulb on the tip of a flexible tube.
Why it mattered. Photographs of the stomach lining helped doctors spot cancers early.
Richard Doll, Austin Bradford Hill, Ernst Wynder and Evarts GrahamLondon, England, and St Louis, USA
In 1950, two large studies, one in the USA and one in Britain, compared people with lung cancer to people without it. Nearly all the patients were smokers. In 1964 the US Surgeon General’s report said plainly that cigarette smoking causes lung cancer.
Why it mattered. It is the main reason doctors and governments now fight tobacco.
Anokhelal Mishra of the Benares gharana was nicknamed Jadugar, the wizard. He could play the pattern 'na dhin dhin na' clearly at astonishing speed. He played on All India Radio and with great musicians like Ali Akbar Khan and Vilayat Khan, but died young at 44.
Why it mattered. His clarity at speed set a standard that tabla students still chase.
Leo Fender made a simple solid guitar with a bolt-on neck, easy to build and fix. It came out in 1950 as the Esquire and Broadcaster, and was renamed the Telecaster in 1951 after a clash over the Broadcaster name. Factories could now make electric guitars like any other product.
Why it mattered. The Telecaster and Esquire were the first mass-produced, commercially successful solid-body electric guitars.
Early heat pump inventors, Hotpoint and Harvey-WhippleUSA
A heat pump works like a fridge run backwards: it pulls heat from the air and pumps it into water. A 1937 US heat pump patent is often named as the first, and in the 1950s Hotpoint and Harvey-Whipple are credited with some of the first heat pump water heaters sold.
Why it mattered. Moving heat instead of making it gives several units of heat for each unit of electricity used.
Frank Philip Bowden and David TaborCambridge, England
In their book The Friction and Lubrication of Solids, Bowden and Tabor showed that surfaces touch only at the tips of their bumps, over a tiny fraction of the area you see. The bumps squash until they can carry the load, so the real contact area grows with the load.
Why it mattered. It finally explained Amontons's laws.
Walter Kistler and Hans Conrad SondereggerWinterthur
Squeeze a quartz crystal and it makes a tiny electric charge. In 1950 Kistler and Sonderegger patented a charge amplifier that could read that charge reliably. Their company, founded in 1959, launched a quartz force sensor in 1961.
Why it mattered. Piezoelectric sensors can measure fast, changing forces, like the punch of an engine or a car crash test.
The German radio maker Braun moved into kitchen machines with the Multimix blender in the early 1950s, and in 1957 it launched the KM 3 kitchen machine. Braun blenders made their way into some Indian homes too.
Why it mattered. A Braun blender that could not cope with Indian grinding is where India's own mixie began.
Tianjin Flying Pigeon Bicycle FactoryTianjin, China
The heavy, black Flying Pigeon PA-02 became a symbol of modern China. Tens of millions were made, and for decades the streets of Chinese cities were rivers of bicycles.
Why it mattered. Often called the most widely used vehicle in history.
Bich bought rights to Bíró's design and used Swiss watchmaking machines to make precise balls cheaply. The Cristal's clear hexagonal barrel shows the ink left, and a tiny hole in the barrel equalises air pressure.
Why it mattered. Bic says it has sold more than 100 billion Cristals: the pen became disposable.
Claude ShannonBell Labs, Murray Hill, United States
Shannon asked people to guess a hidden text one letter at a time. From how often they guessed right, he estimated that English carries only about 1 bit of information per letter, because so much of it is predictable.
Why it mattered. It showed how much of language can be predicted from what came before.
The first commercial devices that wrote with a continuous jet of ink came from Siemens in 1951. They were used for recording instruments, like chart recorders for medical signals, rather than for printing pages.
Why it mattered. It proved that a fine jet of ink could be steered to write.
Stefan Kudelski's Nagra tape recorders were small, tough and ran on batteries. Later models with crystal sync could keep step with a camera without a cable, and from the 1960s to the 1990s they were the standard for recording sound on location.
Why it mattered. They freed production sound from the studio.
Fred Astaire; Stanley Donen; John ArnoldMGM studios, Culver City, California
In Royal Wedding, Fred Astaire seems to dance up the walls and across the ceiling. The whole room was built inside a turning drum, and the camera was fixed to it so it turned with the room. On screen, the room looks still and Astaire looks weightless.
Why it mattered. A rotating set tricks your sense of up and down without any camera trickery at all.
Ilizarov, a country doctor in Siberia, built a frame of metal rings joined by rods, held to the bone by thin wires. He found that if a cut bone is pulled apart very slowly, new bone fills the gap. In 1980 he fixed the leg of Italian explorer Carlo Mauri, and the method spread to the West.
Why it mattered. It showed bone can be coaxed to regrow, to lengthen legs and heal breaks that would not join.
Werner Kuhn, Bartholomäus Hargitay and Heinrich WirzBasel
Kuhn, a physical chemist, and Hargitay argued that the hairpin shape of the loop of Henle could build up saltiness step by step. Wirz measured rat kidneys and found the medulla gets saltier towards the tip. The idea was confirmed by Gottschalk and Mylle in 1958.
Why it mattered. It finally explained what Henle's loop is for: concentrating urine.
Johannes Müller, Emil Schlittler and Hugo Bein, CibaBasel
Chemists isolated the pure alkaloid reserpine from the root. It became one of the first modern drugs for high blood pressure and for severe mental illness. Its side effects, including depression, later made it rare.
Why it mattered. Reserpine research helped Arvid Carlsson show dopamine’s role in the brain, work that won the 2000 Nobel Prize.
Grace Hopper wrote the A-0 system, an early compiler: a program that turns instructions written by people into machine code. Many experts told her computers could only do arithmetic. Her later work led to the business language COBOL.
Why it mattered. Compilers let people write programs in words instead of raw numbers.
Alan Hodgkin and Andrew HuxleyPlymouth and Cambridge
Squid have a giant axon up to about 1 mm wide, big enough to put a wire inside. Hodgkin and Huxley measured how sodium rushes in and potassium flows out, and wrote equations that predict the shape and speed of the spike.
Why it mattered. Their model is still the basis of how we understand every nerve signal.
Eccles put fine electrodes inside spinal motor neurons and recorded how some synapses push the voltage up and others pull it down. He shared the 1963 Nobel Prize with Hodgkin and Huxley.
Why it mattered. It showed a neuron decides by adding up go and stop signals.
Charlotte Anderson, Alastair Frazer and colleaguesBirmingham, England
Charlotte Anderson, an Australian doctor, worked with a Birmingham team measuring how well children with coeliac disease absorbed fat. They showed that gluten, a protein in wheat flour, was the part that did the harm. She later became the first woman professor of paediatrics in the UK.
Why it mattered. Pinning the blame on gluten explained why the damaged gut lining could not soak up food.
The Sonotone 1010 hearing aid used one transistor along with two tiny vacuum tubes. Hearing aids had used vacuum tubes since the 1920s; the transistor made batteries last much longer. Soon all-transistor aids small enough to wear on the ear followed.
Why it mattered. Hearing aids were the first commercial product ever to use the transistor.
Alan Hodgkin and Andrew HuxleyCambridge and Plymouth, England
Working with the giant nerve fibre of the squid, Hodgkin and Huxley measured how sodium flowing in and potassium flowing out create the action potential. Their equations predicted the spike’s shape and speed. They shared the 1963 Nobel Prize with John Eccles.
Why it mattered. It explained the nerve impulse in the language of physics.
A polio epidemic left hundreds of people in Copenhagen unable to breathe, and there were very few iron lungs. The anaesthetist Ibsen put a tube into the windpipe of 12-year-old Vivi Ebert and pushed air in with a squeezed rubber bag. Hundreds of medical students then took turns squeezing bags day and night, and far fewer patients died.
Why it mattered. Pushing air in, instead of pulling it in, is how modern ventilators work, and Ibsen went on to open what is often called the first intensive care unit.
In Collier's magazine von Braun described a wheel about 75 m across, spinning slowly so its crew would have about a third of normal gravity. Artists painted it, and it shaped how films showed space stations for decades.
Why it mattered. It made artificial gravity by spinning a familiar idea.
Doriot Anthony Dwyer won the job of principal flute of the Boston Symphony Orchestra in 1952. She is widely described as the first woman to hold a principal chair in a major American symphony orchestra. She played there for nearly 40 years, until 1990.
Why it mattered. She opened the top jobs in great orchestras to women musicians.
Gibson, Ted McCarty and Les PaulKalamazoo, Michigan, USA
Gibson answered Fender with its own solid-body guitar, named after Les Paul, who helped with the design. It had a carved top and a thick, heavy body. It went on sale in 1952.
Why it mattered. The Les Paul and the Telecaster set the two main styles of solid electric guitar.
Rosalind Franklin and Raymond GoslingKing's College London, England
Working in Franklin's lab, her student Gosling took an X-ray picture of DNA that showed a clear X-shaped pattern. It was shown to James Watson without Franklin's permission in January 1953. The pattern helped Watson and Crick work out that DNA is a double helix.
Why it mattered. An X-ray picture helped reveal the shape of the molecule that carries life's instructions.
Westinghouse, Frigidaire and other makersUnited States
Water vapour in the air freezes onto cold coils as frost, which blocks the cooling and once meant switching the fridge off to chip it away. In the 1950s American makers began selling fridges that defrost themselves: a fan blows air past hidden coils, and a timer switches on a small heater every few hours to melt the frost. Frigidaire, for example, introduced auto-defrost in 1952 and a frost-free model in 1958.
Why it mattered. No more chipping ice, though the heater and fan cost some extra electricity.
For The Beast from 20,000 Fathoms, Harryhausen animated his creature in front of projected live-action footage, then added a foreground layer on top. The method was later sold as Dynamation, a name used from The 7th Voyage of Sinbad (1958).
Why it mattered. It let puppets and actors share the same shot cheaply, long before computer effects.
CinemaScope films such as The Robe carried four magnetic sound tracks on the print: left, centre and right behind the screen, plus a surround channel for effects.
Why it mattered. Speakers behind the screen and effects around the hall became the cinema layout.
20th Century Fox, with Henri Chrétien's lensesNew York, USA
Fox bought old Hypergonar lenses invented by the French astronomer Henri Chrétien. These anamorphic lenses squeeze a wide scene sideways onto normal 35 mm film, and a matching lens unsqueezes it in the cinema. The Robe premiered in CinemaScope in September 1953.
Why it mattered. Anamorphic lenses gave cinema its wide shape and their oval flares and streaks, still loved today.
The Robe premiered in CinemaScope. A special lens squeezed a wide picture onto normal 35 mm film, and another lens stretched it back out on a much wider screen.
Why it mattered. Wide screens helped cinemas compete with television, and wide frames are still the standard.
Vincent du VigneaudCornell University, New York, USA
Du Vigneaud worked out and built oxytocin and then vasopressin, the antidiuretic hormone that tells the kidneys to keep water. He won the 1955 Nobel Prize in Chemistry.
Why it mattered. It put a structure to the body's water-saving signal.
Sven-Ivar SeldingerKarolinska Institute, Stockholm, Sweden
Seldinger put a needle into an artery, slid a thin wire through it, took the needle out and slipped a flexible tube over the wire. His short paper made reaching any big vessel safe and simple.
Why it mattered. Almost every angiogram, stent and heart catheter still starts this way.
Henry Molaison, William Scoville and Brenda MilnerHartford, Connecticut, USA, and Montreal, Canada
To treat severe epilepsy, surgeon William Scoville removed much of both of Henry Molaison’s hippocampi. Afterwards he could not form new lasting memories of events, though he could still learn skills. Psychologist Brenda Milner and others studied him for decades.
Why it mattered. His case showed that the hippocampus is key to forming new memories.
Eugene Aserinsky and Nathaniel KleitmanUniversity of Chicago, USA
Watching sleepers’ eyes and brain waves, Aserinsky and Kleitman found regular periods of rapid eye movement with an active, awake-looking EEG. People woken from them often reported vivid dreams.
Why it mattered. It showed that sleep has distinct stages, and that the brain is busy during it.
John GibbonJefferson Medical College Hospital, Philadelphia, USA
Gibbon spent nearly two decades building a heart-lung machine that pumps blood and adds oxygen outside the body. He used it for 26 minutes while he closed a hole in the heart of Cecelia Bavolek, an 18-year-old student. She recovered.
Why it mattered. It was the first successful open-heart operation using a heart-lung machine, the start of modern heart surgery.
Fuel was so short in 1950s Israel that the government banned heating water between 10 pm and 6 am. The engineer Levi Yissar built a solar water heater at home and in 1953 started NerYah, Israel's first company making them. By 1967 about 50,000 had been sold.
Why it mattered. It showed a country short of fuel could get hot water from its rooftops.
John E. HodgeUS Department of Agriculture lab, Peoria, Illinois, USA
Hodge, an African American chemist, published a paper that laid out the steps of the Maillard reaction as a clear scheme. Food scientists still use his map to understand browning. It became one of the most cited papers in food chemistry.
Why it mattered. Knowing the steps let cooks and engineers control browning instead of guessing.
The US Federal Communications Commission approved a colour TV standard. The clever trick was to add colour as an extra signal, so old black-and-white sets still showed the picture. On 1 January 1954 the Rose Parade became the first nationwide colour broadcast.
Why it mattered. Sending brightness and colour separately is still how colour TV signals are built.
By 1953, sales of automatic washing machines in the United States were higher than sales of wringer washers. In Britain and most of Europe, electric washing machines only became popular in the 1950s, and automatics did not take over in the UK until well into the 1970s.
Why it mattered. Hand-fed wringers slowly gave way to machines that did the whole job.
Film Writers' Association (now the Screenwriters Association)Bombay (now Mumbai), India
Writers working in Indian films formed the Film Writers' Association in 1954. It became a registered trade union in 1960 and lets members register their scripts to protect them. Today, as the Screenwriters Association, it has tens of thousands of members.
Why it mattered. Writers needed a way to prove a story was theirs and to be paid and credited for it.
Andrew Huxley and Rolf Niedergerke; Hugh Huxley and Jean HansonCambridge and London (and MIT)
Two pairs of scientists, working separately, published back-to-back papers in the same issue of Nature. Watching the stripes of living and stretched fibres, both saw the dark A band keep its width while the light bands shrank. The filaments do not shorten: they slide past each other. The two Huxleys were not related.
Why it mattered. The sliding filament theory is how we understand every muscle today.
Joseph Murray and teamPeter Bent Brigham Hospital, Boston
Ronald Herrick gave a kidney to his identical twin, Richard, whose kidneys were failing. Because they were identical twins, the body did not reject the kidney. Richard lived eight more years. Murray shared the 1990 Nobel Prize.
Why it mattered. It proved that a transplanted organ can work, and that one kidney is enough for a donor.
Ustad Ahmed Jan Thirakwa (c. 1892–1976)Rampur and Lucknow
For centuries the tabla mostly accompanied singers and dancers. Ahmed Jan Thirakwa of the Farukhabad gharana became famous for playing it as a solo instrument. In 1954 he received the Sangeet Natak Akademi Award, India's top national honour for performers, and in 1970 the Padma Bhushan.
Why it mattered. He showed audiences that a tabla player could hold a stage alone.
B. S. Ramakrishna and M. M. SondhiIndian Institute of Science, Bangalore
Ramakrishna and Sondhi treated the tabla head as a composite membrane: a light skin with a heavier disc in the middle. Their calculations showed that the right size and weight of disc makes the first several modes almost harmonic. They published it in the Journal of the Acoustical Society of America.
Why it mattered. It explained with maths what Raman had heard, and later researchers still start from it.
Leo Fender, Bill Carson, George Fullerton, Freddie Tavares and othersFullerton, California, USA
Fender’s second solid guitar had a curved, comfortable body, three pickups and a vibrato bar that bends the pitch. Each pickup sits at a different distance from the bridge, so each hears the string’s vibration differently. It went into production in 1954.
Why it mattered. The Stratocaster became one of the most copied guitar shapes in the world.
GE says its Mobile Maid was the first automatic portable dishwasher. Instead of being plumbed in, a portable machine could be rolled up to the kitchen sink and connected to the tap.
Why it mattered. Homes without special plumbing could now have a dishwasher too.
Harold Hopkins and Narinder Singh KapanyImperial College, London
Hopkins and his student Kapany, who was born in Punjab and went to school in Dehradun, lined up thousands of thin glass fibres into a flexible bundle. Each fibre carried one dot of light by total internal reflection, so the bundle carried a whole image round bends. Their paper in Nature named it the fibrescope, and the Dutch scientist Abraham van Heel described coated fibres in the same issue.
Why it mattered. It led to flexible endoscopes that let doctors look inside the body, and in 1960 Kapany coined the term fibre optics.
The Mercedes-Benz 300 SL, shown in New York in 1954, sprayed petrol directly into each cylinder with a Bosch mechanical pump, instead of mixing it in a carburettor. It was one of the first cars to do this. Its gull-wing doors made it famous too.
Why it mattered. Precise fuel injection, now controlled by computers, is how nearly every modern engine is fed.
Western Union placed small Desk-Fax machines in tens of thousands of businesses to send and receive telegrams as pictures. By one history, over 40,000 were in use.
Why it mattered. It was the first time fax machines sat on ordinary office desks.
Jenkins, better known as the science-fiction writer Murray Leinster, received two US patents for front projection. A half-silvered mirror lets a projector beside the camera throw the background along the same line as the lens onto a Scotchlite screen.
Why it mattered. The actor's own body hides the shadow they cast, so the trick is invisible to the camera.
Ray had no written script for Pather Panchali at first. He drew its scenes in pen, brush and ink in a sketchbook, and showed these pictures to people he hoped would fund the film. It came out in 1955 and won prizes around the world.
Why it mattered. A sequence of simple drawings was enough to plan, and to sell, a masterpiece.
From the 1950s, studios moved from scripts that listed every camera shot to master-scene scripts: a heading for each place and time, then action and dialogue. The director works out the shots later. Typed in 12-point Courier, a typewriter font designed in 1955, one page runs roughly one minute on screen.
Why it mattered. A fixed format means anyone can guess a film's length and cost just by counting pages.
Before he had money to make his first film, Ray, a trained illustrator, drew its key moments in pen, brush and ink in a drawing book. He showed these pictures to producers to explain the film. Pather Panchali came out in 1955 and made him world-famous.
Why it mattered. His drawings show a whole film planned in pictures by one person, far from any big studio.
Ray, a commercial artist, made his first film on a tiny budget with mostly new actors, shooting in real villages. It won an award at the Cannes Film Festival in 1956 and made Ray famous around the world.
Why it mattered. It showed the world a new, realistic Indian cinema, and Ray later received an honorary Oscar in 1992.
Jonas Salk and a trial of about 1.8 million childrenPittsburgh and across the USA
A huge field trial showed that Jonas Salk’s killed-virus polio vaccine was safe and effective. Albert Sabin’s weakened, oral vaccine followed, and oral drops later became the main tool of India’s Pulse Polio campaign.
Why it mattered. Polio, which paralysed hundreds of thousands of children a year, could now be stopped.
Geoffrey Harris, with Dora JacobsohnCambridge and London, England, and Lund, Sweden
The pituitary was called the master gland, but what controlled it? Geoffrey Harris showed that tiny blood vessels carry chemicals from the hypothalamus in the brain straight down to the pituitary. With Dora Jacobsohn he showed that cutting this blood link stopped the pituitary working. He summed it up in his 1955 book Neural Control of the Pituitary Gland.
Why it mattered. It joined the nervous system and the hormone system into one control network.
After about ten years of work, Frederick Sanger worked out the exact order of all 51 amino acids in insulin's two chains. It was the first protein ever sequenced, and it won him the 1958 Nobel Prize in Chemistry.
Why it mattered. It proved proteins have exact, readable sequences, which opened the way to making insulin from its gene.
Babies born with biliary atresia have no working bile ducts, and most died within months. At Tohoku University, Kasai joined a loop of intestine straight to the liver so bile could drain out. He reported it in Japanese in 1959, and the world learned of it in English in 1968.
Why it mattered. The Kasai operation still saves or buys time for many babies, some of whom later get transplants.
Electronic organs appeared in the 1930s, and reed organs started to fade in Europe and America. Estey, the last big North American maker, stopped making reed organs in the mid-1950s. By then India had become the harmonium's real home.
Why it mattered. The instrument almost vanished in the West just as it thrived in South Asia.
Kaira District Co-operative Milk Producers' Union (Amul)Anand, Gujarat, India
Prime Minister Jawaharlal Nehru opened Amul's new dairy, which made butter and milk powder from buffalo milk, a world first. Like every butter dairy, it depends on centrifugal separators to take the cream off the milk.
Why it mattered. India's co-operative dairies grew into the world's largest milk industry, with centrifuges at their heart.
A single coil picks up hum from mains wiring as well as the strings. Seth Lover put two coils side by side with opposite magnets, wired so the hum cancels but the string signal adds up. Gibson used it from 1957, and the patent (US 2,896,491) was granted in 1959.
Why it mattered. The humbucker gave a quieter, fatter sound, and most electric guitars now use one or a single-coil design.
Madras Motors and Royal EnfieldMadras (now Chennai), India
After the Indian Army ordered Bullets for patrolling the borders, Royal Enfield and Madras Motors set up Enfield India to assemble them. By 1962 every part was made in India. The Bullet has been built in Chennai ever since, even after the English factory closed.
Why it mattered. It started India's own motorcycle industry, and Royal Enfield eventually became an Indian company.
Erik Odeblad and Gunnar LindströmStockholm, Sweden
After visiting Bloch at Stanford, the Swedish doctor Erik Odeblad built his own NMR equipment and measured human tissues and body fluids. He found that their relaxation times differ.
Why it mattered. It was an early hint that NMR could tell one tissue from another.
Sabapathy, a young apprentice in a Coimbatore workshop, built a wet grinder: granite stones turned by an electric motor inside a drum. It did the aattukkal's job of grinding rice and dal into idli and dosa batter. From 1963 P. B. Krishnamurthy's Lakshmi Grinders made them popular, and in 1975 R. Doraiswamy invented the tilting wet grinder.
Why it mattered. It saved many women hours of grinding and started a whole industry in Coimbatore.
Zenith’s Flash-Matic looked like a ray gun. You pointed its beam of light at one of four photocells in the corners of the screen to change channel or mute. Sadly, bright sunlight could change the channel too.
Why it mattered. It started the idea of controlling a TV from the sofa, which ultrasonic and then infrared remotes made reliable.
Laundry powder left dishes dull when used in a dishwasher. P&G launched Cascade, a detergent made just for automatic dishwashers. Later chemists added things like bleach, enzymes and rinse aids.
Why it mattered. Dishwashers clean with chemistry as much as with water jets.
Burmah Shell began selling LPG in Bombay under the name Burshane. At first cooking gas was a rare city luxury, and most Indian kitchens still burned wood, coal, dung cakes or kerosene.
Why it mattered. It was the first step towards the gas cylinder that now sits under most Indian hobs.
Batteries for telephone and radio equipment needed daily care and wore out in a few years. Fuji Electric built a prototype uninterruptible power supply in 1954 and was delivering units by 1955. A heavy flywheel spun on a motor-generator, and when the mains failed, its momentum kept the generator turning.
Why it mattered. The goal of every UPS was already clear: no gap at all when the power goes out.
Tappan, under licence from RaytheonMansfield, Ohio, and New York, USA
Tappan licensed Raytheon's patents in 1952 and showed an ‘Electronic Oven’ for homes in New York on 27 October 1955. It sold for about $1,300, and few families bought one.
Why it mattered. The home microwave was possible, but it was still too big and costly.
Willis Carrier designed the first modern air-conditioning system in 1902, and window air conditioners appeared in the early 1930s. As they became affordable after the Second World War, ceiling fans faded from American homes.
Why it mattered. For a while, it looked as if the fan's job was done.
Rajkumari Amrit Kaur and the Parliament of IndiaNew Delhi
An Act of Parliament created the All India Institute of Medical Sciences, as the Bhore Committee had proposed, with India’s first health minister, Rajkumari Amrit Kaur, leading the effort. It was to set the standard for medical teaching, patient care and research.
Why it mattered. It became the model for the new AIIMS institutes since set up across India.
Multitone Electric CompanySt Thomas' Hospital, London
Multitone, founded by the inventor Joseph Poliakoff, installed a closed-loop radio paging system at St Thomas' Hospital in London. Doctors carried small receivers that bleeped when they were wanted, instead of being called over loudspeakers.
Why it mattered. Britain's doctors still call a pager a 'bleep' because of it.
British Post Office, AT&T and CanadaOban, Scotland to Clarenville, Newfoundland
TAT-1 carried 35 telephone calls at once across the Atlantic, with 51 amplifiers, called repeaters, sealed along the sea bed. In its first 24 hours it carried 588 calls between London and the US.
Why it mattered. Undersea cables made international calls clear and common; their fibre successors carry the internet today.
Films Division, with Disney animator Clair WeeksBombay (Mumbai)
The Government of India invited Clair Weeks to set up a Cartoon Film Unit at Films Division and train Indian animators. Among the first recruits was a young Ram Mohan.
Why it mattered. It trained the first generation of Indian studio animators.
Mitra began filming with Ray on Pather Panchali (1955) when he was 21. For Aparajito, fear of the monsoon moved a Benares courtyard set into a Calcutta studio, so Mitra stretched a white cloth over it like a patch of sky and bounced studio lights off it. The result looked like soft, shadowless daylight.
Why it mattered. Mitra is widely credited as a pioneer of bounce lighting, now one of the most common ways to make soft light.
For thirty years textbooks said humans had 48 chromosomes. Using better ways to spread cells out on a slide, Joe Hin Tjio counted 46 again and again, and he and Albert Levan published the result.
Why it mattered. It fixed the number at the heart of this box: 23 from each parent, 46 in all.
Vulimiri Ramalingaswami and colleaguesKangra Valley, Himachal Pradesh, India
In the Himalayan foothills, goitre was very common. Researchers split the valley into zones: some families got salt with added iodine, others got plain salt. In the iodised zones, goitre became much less common.
Why it mattered. It proved that iodised salt could prevent goitre across a whole population.
Helen Free and Alfred FreeMiles Laboratories, Elkhart, Indiana, USA
The Frees and their team made Clinistix, a paper strip that changes colour when dipped in urine containing glucose. Strips for many other tests followed.
Why it mattered. Urine testing became quick, cheap and possible at home.
Charles Thiel, George Maison, Irving Porush and Susie MaisonRiker Laboratories, California, USA
Thirteen-year-old Susie Maison had asthma and hated her clumsy squeeze-bulb nebuliser. She asked her father why her medicine could not come in a spray can, like hairspray. His company, Riker Laboratories, made the Medihaler, which was approved in the USA in March 1956.
Why it mattered. A pocket spray that sends medicine straight into the airways is still how most people treat asthma.
Richard Pattle and John ClementsPorton Down, England, and Maryland, USA
While studying how nerve gases harm the lungs, Pattle in Britain noticed that foam from lungs was unusually long-lasting. Clements in the USA measured lung fluid on a special balance and showed it could make surface tension very low. The substance was named surfactant.
Why it mattered. Surfactant stops the tiny air sacs from collapsing each time you breathe out.
Werner Forssmann, André Cournand and Dickinson RichardsStockholm, Sweden
Cournand and Richards, working in New York from 1941, turned Forssmann's daring experiment into a safe way to measure pressure and oxygen inside the heart. In 1956 the three shared the Nobel Prize in Physiology or Medicine.
Why it mattered. Catheters became one of the main tools for studying and later treating the heart.
Working part-time as a hospital physicist, Cormack wondered how radiotherapy could be planned without knowing how X-rays were weakened inside each part of the body. He began working out how the inside could be calculated from measurements taken outside.
Why it mattered. It was the first time someone set out to compute a map of the body's attenuation.
Clyde Cowan and Frederick ReinesSavannah River Plant, South Carolina
Cowan and Reines placed big tanks of liquid next to a nuclear reactor, which sends out huge numbers of neutrinos. They picked up about three neutrino hits an hour and sent Pauli a telegram with the news. Reines shared the 1995 Nobel Prize in Physics for the discovery.
Why it mattered. Pauli's rescue of energy conservation was proved right, 26 years after his letter.
Russell Kirsch and colleaguesNational Bureau of Standards, Washington DC, United States
Russell Kirsch's team built a drum scanner for SEAC, one of the first programmable computers in the US. The first picture they fed in was a photo of his three-month-old son, Walden, turned into a grid of 176 × 176 pixels.
Why it mattered. For the first time a photo became numbers inside a computer, the starting point of all image processing.
Frank RosenblattCornell Aeronautical Laboratory, Buffalo, United States
Psychologist Frank Rosenblatt wrote a report describing the perceptron, a machine that could learn to sort patterns by adjusting its weights after each mistake. He soon tested the idea as a program on an IBM 704 computer.
Why it mattered. For the first time, an artificial neuron came with a rule for learning from examples.
Casio's first product, the 14-A, used 342 electric relays to add, subtract, multiply and divide 14-digit numbers. It weighed about 140 kg and cost 485,000 yen.
Why it mattered. It showed that calculators could be electric, with no gears, years before the chip.
The first film by the newly trained team was The Banyan Deer. Its title points to an old Indian Jataka tale about a deer king who offers his life to save another deer.
Why it mattered. India’s studio animation began with an Indian story.
Burnet proposed that each lymphocyte carries a receptor of one shape. When a germ fits it, that one cell is selected and multiplies into a clone of identical cells, some of which remember the germ. Experiments soon proved him right.
Why it mattered. It explains how the immune system learns and remembers, the heart of chapters 3 and 4.
Andrew Huxley proposed that side-pieces on myosin attach to actin, pull, and let go, over and over. The same year Hugh Huxley saw these cross-bridges in electron micrographs.
Why it mattered. The cross-bridge cycle in chapter 3 grew from this model.
E. Donnall Thomas and colleaguesCooperstown, New York, USA
The soft marrow inside bones makes blood cells. Thomas and his team reported giving patients marrow through a drip after strong radiation and chemotherapy. Most early attempts failed, but decades of work made bone marrow transplants a cure for some leukaemias.
Why it mattered. It turned the inside of bones into a treatment. Thomas shared the 1990 Nobel Prize for it.
With the physicist Wilbur Peters and the student Larry Curtiss, the South African-born doctor Hirschowitz made a flexible scope from a bundle of thin glass fibres that carry light round bends. He passed it down his own throat first.
Why it mattered. The flexible endoscope let doctors look inside the gut without surgery.
Couinaud studied the vessels and bile ducts inside the liver. He showed it is made of eight segments, each with its own blood supply and bile drain, first in 1954 and then in his 1957 book Le Foie. The outside shape of the liver, he found, does not match how it works inside.
Why it mattered. Surgeons can remove segments safely, and that makes split and living-donor transplants possible.
Working with the physicist Wilbur Peters and the student Larry Curtiss, the South African-born doctor Hirschowitz made a flexible scope from a bundle of thin glass fibres that carry light around bends. He first passed it down his own throat, then a patient’s a few days later. Production models followed in 1960.
Why it mattered. The flexible fibreoptic endoscope changed gastroenterology for good.
Djourno and Eyriès placed a coil and electrode on the auditory nerve of a deaf patient. With electrical pulses he could sense sounds and some rhythm of speech, though not understand words.
Why it mattered. It was the first implanted device to create hearing by electricity, the seed of the cochlear implant.
Forrest Bird, a pilot and inventor who had worked on oxygen masks for high-flying airmen, designed a small ventilator that pushed air into the lungs through a mask or tube. The Bird Mark 7 became one of the first mass-produced, reliable ventilators.
Why it mattered. Small ventilators could be used on any hospital ward, not just in a room of iron lungs.
Harry Olson and Herbert Belar (RCA); Milton BabbittColumbia University, New York, USA
Engineers at RCA built the Mark II Sound Synthesizer, and in 1957 it was delivered to Columbia University. Composers programmed it by punching holes in a long roll of paper, like a player piano. The Columbia-Princeton Electronic Music Center grew around it from 1959, and composer Milton Babbitt used it for years.
Why it mattered. It was the first programmable synthesizer: music written as data that a machine plays back, the idea behind every sequencer.
Sputnik 1, a polished 58 cm ball with four antennas, was launched into orbit. It went round the Earth about every 96 minutes, beeping radio signals that anyone could hear. It was Newton's cannonball made real.
Why it mattered. It began the space age: every satellite since has used the same balance of falling and sideways speed.
Hoover had opened a washing machine factory at Merthyr Tydfil in 1948. Its Hoovermatic twin tub had one tub to wash and a second, smaller tub that spun the clothes to throw the water out. Twin tubs were popular in Britain in the 1960s because they were cheaper than automatics.
Why it mattered. The spin dryer replaced the dangerous power wringer, and twin tubs are still sold where water and power are limited.
Gordon Hall, Frank W. ‘Bill’ Gutzwiller and General ElectricClyde, New York, USA
Building on ideas from Shockley and Bell Labs, a GE team made the silicon controlled rectifier, or thyristor. A tiny pulse at its gate could switch a large current on. GE introduced it in 1957, and in 2019 the IEEE named it a Milestone.
Why it mattered. It started the move from spinning machines and glowing tubes to solid-state inverters.
Soviet space programme, Sputnik 1Baikonur Cosmodrome, Kazakh SSR
A rocket pushed hot gas backwards and was pushed forwards in return, lifting Sputnik 1 into orbit. From then on, the satellite kept falling towards Earth but moved sideways fast enough to keep missing it.
Why it mattered. It was the first human-made object to orbit Earth, steered entirely by Newton's laws.
Frank Rosenblatt and the US Office of Naval ResearchWashington, D.C., United States
At a US Navy press event, a perceptron running on an IBM 704 learned to tell cards marked on the left from cards marked on the right after about 50 tries. The next day The New York Times said the Navy expected such machines to one day walk, talk, see and write. Rosenblatt's full paper came out in Psychological Review later that year.
Why it mattered. It was a real step, but the hype ran far ahead of what one layer of neurons could do.
Jack Kilby (Texas Instruments) and Robert Noyce (Fairchild)Dallas, Texas and Mountain View, California
In 1958 Jack Kilby built several parts of a circuit on one piece of germanium. In 1959 Robert Noyce patented a way to make whole circuits on flat silicon, with metal wires printed on top. Kilby won the 2000 Nobel Prize in Physics, and both are credited as inventors.
Why it mattered. Putting many transistors on one chip made computers smaller, cheaper and faster every year.
Ian Donald, John MacVicar and Tom BrownGlasgow, Scotland
A Glasgow obstetrician, Ian Donald, worked with a doctor and an engineer to adapt an ultrasound machine used for finding cracks in metal. Their paper in The Lancet showed pictures of the inside of the belly made with sound echoes. Soon ultrasound could show a growing baby safely, without X-rays.
Why it mattered. Ultrasound scans became a routine, safe way to check a baby's growth.
Aaron Lerner was studying skin colour. An old report said cow pineal glands made tadpole skin go pale, so he processed thousands of pineal glands. He isolated a new hormone and called it melatonin.
Why it mattered. Melatonin turned out to be the hormone that tells the body it is night.
Tuberculosis Chemotherapy Centre (Wallace Fox and Indian colleagues)Madras (now Chennai), India
A research centre opened in Madras in 1956, supported by ICMR, the Madras government, WHO and Britain's Medical Research Council. It gave 193 TB patients the same pills for a year, half at home and half in a sanatorium. Patients treated at home did almost as well, and their families were not put at extra risk.
Why it mattered. It helped close sanatoria around the world and led to treating TB at home, the basis of India's TB care today.
Rune Elmqvist and Åke SenningKarolinska Hospital, Stockholm, Sweden
Arne Larsson's heart kept stopping, up to 30 times a day. Engineer Rune Elmqvist cast a small pacemaker in resin, using a plastic cup as a mould, and surgeon Åke Senning put it under his skin. The first one failed within hours, but Larsson went on to use 26 pacemakers and lived to 86.
Why it mattered. A tiny electric device could now keep the heart's rhythm for years.
Oram helped create the BBC Radiophonic Workshop in 1958 and was its first studio manager. She soon left to build her own studio at home, the first independent electronic studio run by a woman. From 1962 she designed the Oramics machine, where you drew shapes on strips of 35mm film and light sensors turned the drawings into sound.
Why it mattered. Drawing the shape of a sound to hear it is the same idea as choosing a waveform on a synth.
Link Wray wanted his record to sound as raw as his live shows, so he poked a pencil through his amplifier’s speaker cone. "Rumble" was full of fuzzy, overdriven power chords, and some radio stations refused to play it. It reached No. 16 on the US pop chart.
Why it mattered. Distortion went from an accident to something guitarists did on purpose.
Honda built a light, reliable 50 cc step-through with an automatic clutch, so you could ride it with one hand while carrying a tray of noodles in the other. It was cheap, frugal and nearly unbreakable.
Why it mattered. More than 100 million have been made: the most of any motor vehicle in history.
In 1958 Godrej & Boyce became the first Indian company to make refrigerators, working with General Electric. Before that, the few fridges in India were imported and costly.
Why it mattered. Making fridges at home in India was the first step toward one in every Indian kitchen.
Charles David KeelingMauna Loa Observatory, Hawaii
Keeling began measuring carbon dioxide in the air with great precision, high on a Hawaiian volcano. His record, the Keeling Curve, rises every year, with a small wobble as plants grow and die with the seasons.
Why it mattered. It shows the conservation of mass on a planetary scale: the carbon we burn does not vanish, it stays in the air.
Faber began in 1955 making plastic goods, and in 1958 made what it calls the first kitchen hood of plexiglass. The small town of Fabriano went on to become a world centre for cooker hoods, home to both Faber and Elica.
Why it mattered. Mass-made hoods for home kitchens came out of Fabriano, and both of its big brands later built factories in India.
Tuberculosis Chemotherapy Centre, Madras (ICMR, WHO and MRC)Madras (Chennai)
Patients with tuberculosis were randomly given medicines either in a sanatorium, with rest and good food, or at home in the city’s poor neighbourhoods. A year later both groups had done about equally well, and families at home were not infected more often.
Why it mattered. This Indian randomised trial changed TB care worldwide: medicines, not sanatoriums, cure tuberculosis. The centre is today’s ICMR National Institute for Research in Tuberculosis.
David Hubel and Torsten WieselJohns Hopkins University, Baltimore, United States
Recording from single brain cells in the visual cortex of cats, Hubel and Wiesel found cells that fired only for a line or edge at a particular angle and place. Later work showed more complex cells that combine them.
Why it mattered. The idea of simple edge detectors feeding more complex ones inspired the layered design of convolutional networks, loosely.
Volder published CORDIC, a way to find sines, cosines and other functions with nothing but shifts, adds and a small table of angles. It was invented for aircraft navigation computers.
Why it mattered. Scientific calculators, starting with the HP-35, used this kind of shift-and-add method for trigonometry.
Twenty years after Carlson's first copy, his idea became the Xerox 914, the first automatic plain-paper office copier. It made copies in seconds on ordinary paper and was a huge success.
Why it mattered. It turned xerography into a machine, with a drum, toner and a fuser: the laser printer's direct parent.
Early bluescreen left ugly outlines around actors. Vlahos worked out a colour-difference method that compares the blue and green in each part of the picture to make a much cleaner matte, and refined it for Ben-Hur. In 1976 he and his son founded Ultimatte to build keying machines.
Why it mattered. His colour-difference idea is still at the heart of how keying software pulls a clean edge.
Yakima Canutt; Andrew Marton; A. Arnold GillespieCinecittà Studios, Rome
Ben-Hur's chariot race was filmed on an arena covering 18 acres, the largest film set ever built at that time. The race took five weeks of filming spread over three months. The film went on to win 11 Oscars, including one for special effects.
Why it mattered. It set the standard for real, full-size action that audiences still compare against.
Kaagaz Ke Phool was India's first film in CinemaScope. For the song Waqt Ne Kiya Kya Haseen Sitam, Murthy made a solid-looking shaft of light fall across a dark studio floor. He did it with two large mirrors that reflected real sunlight into the studio.
Why it mattered. It is one of Indian cinema's most famous images, made with sunlight and mirrors rather than lamps.
General Electric patented a practical tungsten-halogen, or quartz, lamp in 1959. That year Ross Lowell started Lowel-Light, which made small, light halogen fixtures and clamps that a crew could carry to a real location. In 1980 he won a technical Academy Award for his compact lighting system.
Why it mattered. Halogen lamps are brighter and keep their colour better than old bulbs, and they filled film lights for decades.
Rosalyn Yalow and Solomon BersonBronx Veterans Administration Hospital, New York, USA
Yalow and Berson invented radioimmunoassay, a way to measure tiny amounts of insulin in blood. They found that many people with type 2 diabetes have plenty of insulin, not too little. Yalow won the 1977 Nobel Prize; Berson had died in 1972.
Why it mattered. It showed that type 2 diabetes is often about insulin not working well, and transformed hormone testing.
David Hubel and Torsten WieselJohns Hopkins University, Baltimore
Recording from single cells in the visual cortex, Hubel (from Canada) and Wiesel (from Sweden) found cells that respond to edges and lines at particular angles. They shared the 1981 Nobel Prize.
Why it mattered. It showed how the brain builds pictures out of simple features from the eyes.
David Hubel and Torsten WieselJohns Hopkins University, Baltimore, USA
Hubel, from Canada, and Wiesel, from Sweden, recorded single neurons in the visual cortex and found each fired for lines at a particular angle. Vision is built up from simple features. They shared the 1981 Nobel Prize.
Why it mattered. It showed how the visual cortex turns light into shapes, step by step.
Mary Ellen Avery and Jere MeadHarvard School of Public Health, Boston, USA
Many babies born too early died of hyaline membrane disease, and nobody knew why. Avery and Mead tested fluid from the lungs of babies who had died and found it was missing surfactant. Without it, the babies’ air sacs collapsed with every breath.
Why it mattered. Their discovery led to surfactant treatment, which has saved hundreds of thousands of newborn babies.
H. D. Vasudeva, Pressure Cookers and Appliances LtdMumbai, India
H. D. Vasudeva started the company at 54, with Rs 20,000, in technical partnership with L. G. Hawkins of England. Its cookers trap steam so water boils at about 120 °C, and dal and rice cook much faster. The firm was renamed Hawkins Cookers Ltd in 1986 and says it has sold more than 140 million cookers and pans.
Why it mattered. Papin's digester became the whistle heard in kitchens across India.
Barényi split the car into a rigid cabin with front and rear zones designed to fold up in a crash (German patent 854157, 1952). The Mercedes-Benz W111 'Fintail' saloon of 1959 was the first car built fully this way. A longer crush means a longer stop, so less force on the people inside.
Why it mattered. Impulse, F × Δt = Δp, became the rule of car safety.
India’s television began as an experiment in Delhi, with a small transmitter and a makeshift studio. Daily service began in 1965, with a news bulletin read by Pratima Puri. In 1976 Doordarshan became separate from radio.
Why it mattered. It was the start of what grew into one of the world’s biggest TV audiences.
Charles Reid and E. J. BretonUniversity of Florida, USA
Reid and Breton showed that thin films of cellulose acetate, a kind of plastic, let water through but held back most of the salt. The trouble was that water crept through far too slowly to be useful.
Why it mattered. It proved that a plastic skin could desalt water, if only it could be made faster.
Nils Bohlin, who had designed ejection seats for Saab jets, joined Volvo and created a belt that holds both the hips and the chest, clipped in with one hand. Volvo fitted it to its cars in 1959. It then left the patent open so every carmaker could use the design for free.
Why it mattered. The three-point belt is credited with saving at least a million lives, more than any other car safety invention.
Frank Rosenblatt and teamCornell Aeronautical Laboratory, Buffalo, United States
The Mark I Perceptron was shown to the public. Its weights were motor-driven knobs (potentiometers), and a camera of 400 light cells fed it pictures. Once set, the knobs turned inputs into an answer with no computer program at all.
Why it mattered. It showed that a network's answer is just inputs times weights, added up: something you can build in hardware.
Frank Rosenblatt and teamCornell Aeronautical Laboratory, Buffalo, United States
The Mark I Perceptron was a large machine built for image recognition. Its camera was a grid of 20 by 20 light sensors, just 400 pixels, and its weights were dials turned by small electric motors. It was shown in public in June 1960.
Why it mattered. It was one of the first machines built to learn to recognise simple pictures.
Bernard Widrow and Ted HoffStanford University, United States
Bernard Widrow and his student Ted Hoff built ADALINE, a single artificial neuron that nudged its weights to shrink its error bit by bit. Their learning rule, now called the delta rule or least mean squares, is still used.
Why it mattered. A version of it was later used to cancel echoes on phone lines, often called one of the first real-world uses of a neural network.
Rangaswamy Narasimhan and team, TIFRBombay (now Mumbai)
A team at the Tata Institute of Fundamental Research built India's first home-made digital computer, based on the IAS machine design from Princeton. It used about 2,700 vacuum tubes and an early ferrite core memory. It was commissioned in 1960, and Prime Minister Nehru gave it its name; sources differ on whether that was in 1960 or 1962.
Why it mattered. It showed that India could design and build its own computers.
Motorola engineers under John F. Mitchell combined ideas from walkie-talkies and car radios to make a transistorised pager, small enough to carry. The same team later helped build the first handheld mobile phone.
Why it mattered. Transistors made pagers pocket-sized and battery-friendly.
Subscriber trunk dialling, STD, let callers dial another city themselves instead of booking a 'trunk call' through an operator. India's first STD route linked Lucknow and Kanpur.
Why it mattered. It was the first step from waiting hours for a trunk call to dialling any city at once.
Kazuo Miyagawa, for director Kon Ichikawa's Her BrotherKyoto, Japan
Miyagawa, a cinematographer who had studied chemistry, left out the bleach step when developing the film. Silver stayed in the picture, so colours looked washed out and blacks looked harder. The trick is called bleach bypass.
Why it mattered. It gave film makers a gritty, silvery look that is still copied in digital grading today.
Jean-Luc Godard, editor Cécile DecugisParis, France
Godard's first feature cut chunks out of continuous shots, so the characters seem to jump forward in time. Mainstream editors had worked hard to hide such cuts.
Why it mattered. It made the jump cut a deliberate style. Today it is everywhere, from music videos to vlogs.
For Mughal-e-Azam, a Sheesh Mahal set about 150 feet long was covered in small Belgian glass mirrors made by workers from Firozabad. It took two years to build. Cinematographer R. D. Mathur tamed the glare with wax on the mirrors and cloth strips to bounce the light for the song Pyar Kiya To Darna Kya.
Why it mattered. It shows how a set and clever lighting can be a special effect on their own.
For Breathless (1960), Coutard shot handheld in real streets and rooms with natural light, on fast Ilford HPS film. For interiors he later hung small lights just below the ceiling and bounced them off white cards up there. The light looked like it came from the room itself.
Why it mattered. It helped make natural-looking, low-budget lighting fashionable around the world.
Saul Bass and Alfred HitchcockUniversal Studios, Los Angeles, USA
Hitchcock was famous for planning every shot before filming. For Psycho he hired the designer Saul Bass as pictorial consultant, and Bass storyboarded the shower scene as dozens of quick, tight shots. Who deserves the most credit is still argued about, but the actor Janet Leigh said Hitchcock followed Bass's storyboard precisely.
Why it mattered. It showed how a storyboard can decide the size, angle and order of every shot in a scene.
Rosalyn Yalow and Solomon BersonBronx Veterans Administration Hospital, New York, USA
Hormones float in the blood in astonishingly tiny amounts. Yalow and Berson used antibodies and a little radioactivity to measure insulin in human blood for the first time. They called the method radioimmunoassay and did not patent it.
Why it mattered. Doctors and scientists could finally measure hormones, and Yalow won the 1977 Nobel Prize.
Arvid Carlsson, Oleh Hornykiewicz, George CotziasLund, Vienna and New York
Carlsson showed dopamine is a transmitter in its own right. Hornykiewicz found it missing in the brains of people who had Parkinson’s disease, and Cotzias made high-dose L-dopa an effective treatment by 1967.
Why it mattered. It was the first time a brain disease was treated by replacing a missing transmitter.
At a meeting in Prague, the biochemist Robert Crane proposed that gut lining cells pull in glucose and sodium together, through the same doorway. Many experts doubted him, but he was right.
Why it mattered. It is why a drink of salt and sugar can rehydrate a person even during severe diarrhoea.
Peter Safar, James Elam, William Kouwenhoven, James Jude and Guy KnickerbockerBaltimore, USA
Safar and Elam showed that a rescuer's breath, blown mouth-to-mouth, can fill another person's lungs. In 1960 Kouwenhoven, Jude and Knickerbocker showed that pressing on the chest keeps blood moving. That year the two ideas were joined into CPR.
Why it mattered. Anyone can learn it, and it can keep oxygen reaching the brain until help arrives.
Belding Scribner, with Wayne Quinton and David DillardUniversity of Washington, Seattle
Scribner's team made a U-shaped Teflon tube that stayed in a patient's arm, joining an artery to a vein, so dialysis could be repeated for years. Their first patient, Clyde Shields, lived more than 11 years. The first outpatient dialysis centre opened in Seattle in 1962.
Why it mattered. Dialysis changed from a one-off rescue into a treatment people could live on.
Robert K. CranePrague, Czechoslovakia (worked in St. Louis, USA)
At a meeting in Prague, the American biochemist Robert Crane proposed that gut lining cells pull in glucose and sodium together, through the same doorway. The sodium carries the sugar in with it. Many experts doubted him at first, but he was right.
Why it mattered. It is the reason a drink of salt and sugar can rehydrate a person even when diarrhoea is pouring water out.
Nina Starr BraunwaldNational Institutes of Health, Bethesda, USA
Surgeon Nina Starr Braunwald designed and made an artificial mitral valve with flexible plastic flaps. She led the team that put it into a 44-year-old woman, the first successful replacement of that valve with a human-made one. She was 32.
Why it mattered. Worn-out valves, the heart's one-way doors, could now be replaced.
William Kouwenhoven, James Jude and Guy KnickerbockerJohns Hopkins, Baltimore, USA
An electrical engineer, a surgeon and a young engineer found that pushing down hard and fast on the breastbone squeezes the heart enough to move blood. They reported it in a short paper in 1960. With rescue breathing, it became cardiopulmonary resuscitation, or CPR.
Why it mattered. Anyone with training and two hands can keep blood moving until help arrives.
11th General Conference on Weights and MeasuresParis
The new International System of Units named the unit of magnetic flux density after Nikola Tesla, the inventor of the rotating-field induction motor. One tesla is a strong field: 20,000 times the Earth's.
Why it mattered. It gave the whole world one unit for field strength, from microtesla compasses to 3 T scanners.
Arthur H. BenadeCase Institute of Technology, Cleveland, USA
The physicist Arthur Benade published a mathematical theory of how open and closed finger holes change the air column in a woodwind. He showed that a row of open holes acts like the end of the tube for low notes, but lets higher sounds leak past.
Why it mattered. It explained why hole size and spacing shape both the tuning and the tone of a flute.
The International System of Units, adopted in 1960, measures torque in newton-metres. The SI Brochure keeps the joule for energy only, even though both are a newton times a metre.
Why it mattered. One unit, two meanings: the rule stops torque being mistaken for energy.
Jacques Piccard and Don WalshChallenger Deep, Pacific Ocean
Auguste Piccard's bathyscaphe design hung a small steel sphere under a float full of petrol, which is lighter than water and hardly squashes. Trieste dropped iron shot to come back up. With his son Jacques and US Navy officer Don Walsh aboard, it reached about 10,900 m in the Mariana Trench.
Why it mattered. Buoyancy control took people to the bottom of the ocean and back.
Jacques Piccard and Don WalshMariana Trench, Pacific Ocean
The bathyscaphe Trieste sank for nearly five hours to the deepest point in the ocean, measured then at about 10,900 m. Down there the water presses with roughly 1,086 bar, over a thousand times the air pressure at the surface. A window pane cracked on the way down, but the two men spent twenty minutes on the bottom.
Why it mattered. Humans reached the place of greatest pressure in any ocean on Earth.
Soviet records credit Vladislav Ivanov, a young air-force officer, with applying for an inventor's certificate for a way to image the inside of objects with magnetic resonance. It was rejected as unrealistic and only granted in 1984.
Why it mattered. It shows the idea of MR imaging was in the air long before the first pictures.
11th General Conference on Weights and MeasuresSèvres, France
The new International System of Units, the SI, made the joule (a newton times a metre) its unit of energy and work, and the watt (a joule per second) its unit of power.
Why it mattered. One set of units now serves physics, engineering and your electricity bill.
Sidney Loeb and Srinivasa SourirajanUniversity of California, Los Angeles, USA
Loeb, an American engineer, and Sourirajan, a chemist from India, made a cellulose acetate membrane with a very thin, dense skin on a spongy support. Water could be pushed through fast while salt stayed behind. The breakthrough was announced in August 1960.
Why it mattered. It made reverse osmosis practical. In 1965 a plant in Coalinga, California, began supplying drinking water with it.
Miele launched the G 10, which it describes as a fully automatic front-loading dishwasher with rotating spray arms. Nobody had to pour in hot water any more: the machine ran the whole wash on its own.
Why it mattered. Load it, start it and walk away: this is how dishwashers have worked ever since.
Matsushita Electric (National, now Panasonic)Osaka, Japan
The MR-500 was Japan's first dishwasher, reflecting founder Konosuke Matsushita's hope of freeing women from housework. It was as big as a washing machine and expensive, so few people bought it. Japanese makers later became known for small dishwashers that sit on the counter.
Why it mattered. Small kitchens needed small machines, and Japan led the way.
Sidney Loeb and Srinivasa SourirajanUCLA, Los Angeles, USA
Loeb and the Indian-born chemist Srinivasa Sourirajan found a way to cast cellulose acetate so that it had a very thin, dense skin on top of a spongy support. Water flowed through far faster, and salt still stayed behind. Their patent was filed in 1960 and granted in 1964.
Why it mattered. This was the first practical reverse osmosis membrane, the ancestor of the one in every RO purifier.
Yost flew the first modern hot-air balloon, with a plastic envelope and a propane burner he designed. The burner heats the air inside, the air expands, some spills out, and the balloon gets lighter. It flew for about 25 minutes. Almost every hot-air balloon today uses his design.
Why it mattered. It is Charles's law you can ride in.
ANITA, the first all-electronic desktop calculator
Bell Punch Company (Sumlock Comptometer)London, UK
The ANITA Mk VII and Mk VIII were shown at the Business Efficiency Exhibition in London in October 1961. They used vacuum tubes and cold-cathode tubes instead of gears, with glowing Nixie tubes for digits. For over two years they were the only electronic desktop calculators in the world.
Why it mattered. Calculating became silent and electronic.
Doctors had long thought the thymus was useless. Miller removed it from newborn mice and found they could not reject skin grafts or fight infections well. The thymus, he showed, makes the lymphocytes later called T cells.
Why it mattered. It found where T cells are trained.
Working with ears from cadavers and very fine instruments, Békésy watched waves run along the basilar membrane, each pitch peaking at its own place. He won the Nobel Prize in Physiology or Medicine in 1961.
Why it mattered. He showed how the cochlea sorts sound by pitch, the idea behind the cochlea chapter.
Dr N. GopinathChristian Medical College, Vellore, India
Surgeon N. Gopinath used a heart-lung machine to close a hole between the heart's lower chambers. It is widely recorded as the first open-heart operation in India. Surgeons in Bombay were working towards the same goal at the time.
Why it mattered. It began the growth of open-heart surgery in India.
Oldendorf, a neurologist at UCLA, built a working model from his son's toy train, a record-player turntable and an alarm-clock motor. It picked out a nail hidden inside a ring of other nails, like something deep inside a skull. He was granted a US patent in 1963, but companies were not interested.
Why it mattered. It showed cross-sectional imaging could work, years before computers made it practical.
Toshiba, which had made what it calls Japan's first 1-horsepower window air conditioner in 1953, released what it calls the world's first split air conditioners. The noisy compressor sits outside, and a slim unit on the wall inside blows the cool air, joined by thin copper pipes.
Why it mattered. The split system became the most common air conditioner on Earth.
Rolf Landauer; tested by Antoine Bérut and colleaguesIBM, New York; tested in Lyon, France
Landauer, a physicist at IBM, argued that erasing one bit of information must release a tiny minimum amount of heat. That link between information and entropy helped Charles Bennett explain in 1982 why Maxwell's demon cannot break the second law. In 2012 a team in Lyon trapped a single tiny bead with a laser and measured the heat, and it matched Landauer's limit.
Why it mattered. It showed that information is physical, and it sets a floor on how little energy computers can use.
AT&T, Bell Labs, NASA and partnersUSA, UK and France
The Telstar 1 satellite relayed the first live television pictures and telephone calls across the Atlantic. Later satellites were parked in geostationary orbit, 35,786 km up, which adds about a quarter of a second each way.
Why it mattered. Satellites connected places cables could not reach, but their delay made chatting awkward.
In Lawrence of Arabia, Lawrence blows out a match and the film cuts straight to the sun rising over the desert. Coates won the Academy Award for editing.
Why it mattered. It became one of the most admired match cuts in film.
Building on the Kangra results, India launched the National Goitre Control Programme. It surveyed areas where goitre was common and supplied iodised salt to them. The whole cost was paid by the central government.
Why it mattered. It was one of India's first national programmes to prevent a hormone problem with food.
John CharnleyWrightington Hospital, Lancashire, England
Charnley replaced worn hip joints with a small metal ball on a stem and a plastic cup, fixed with bone cement. His first plastic, Teflon, wore away and irritated the body. In November 1962 he switched to a tough polyethylene, and it worked for many years.
Why it mattered. Hip replacement became one of the most common and successful operations in the world.
India started a national programme to fight TB in every district. It used BCG vaccination, chest X-rays to find patients and medicines such as streptomycin and isoniazid, often given at home, as the Madras study had shown was possible.
Why it mattered. It was India's first attempt to fight its biggest lung disease across the whole country.
Stanley Cohen found a protein that made newborn mice open their eyes and grow teeth early. He named it epidermal growth factor, because it makes skin cells multiply. He shared the 1986 Nobel Prize with Rita Levi-Montalcini for the discovery of growth factors.
Why it mattered. It revealed one of the chemical messages that tell skin to renew itself and heal.
Shapiro filled a round tank about 2 m across, let it stand still for a day, then pulled the plug. Only then did the Earth's tiny Coriolis effect show, as a slow anticlockwise swirl. A team in Sydney repeated it in 1965 and saw a clockwise swirl.
Why it mattered. It proved the effect is real, and also that it is far too weak to steer an ordinary sink.
Glenn Snoddy and Revis Hobbs; Gibson (Maestro)Nashville, Tennessee, USA
In 1961 a faulty mixing desk in Nashville turned a guitar part fuzzy on a Marty Robbins record. Two engineers built a circuit to make that sound on purpose, and Gibson sold it in 1962 as the Maestro FZ-1 Fuzz-Tone. After Keith Richards used one on "Satisfaction" in 1965, sales jumped.
Why it mattered. Clipping the top off the signal adds new harmonics, and that sound became the voice of rock.
Sharp developed Japan's first microwave oven, the R-10, in 1961, and in 1962 began making them in large numbers. Toshiba also began production in 1962. Sharp sold them to businesses first, because people doubted they would ever cook without a flame at home.
Why it mattered. Japan began to become the centre of microwave oven making.
Wilson and Trickey described a DC motor whose brushes were replaced by electronic switches that feed each coil at just the right moment. Brushless DC motors later spread to computer cooling fans, where they are now used almost everywhere.
Why it mattered. Electronic control opened the way to fan motors that waste much less power.
In his PhD thesis, Lawrence Roberts wrote a program that found the edges of simple blocks in a photo and worked out their 3D shapes. It only worked for plain, clean polyhedra, not messy real scenes.
Why it mattered. Often called the first computer vision thesis, it set the goal of turning pixels into an understanding of 3D objects.
The Bell System offered push-button 'Touch-Tone' phones to the public. Each key sends two tones at once, one for its row and one for its column. The same tones still work when a helpline says 'press 1'.
Why it mattered. Dialling became faster, and the keypad became a way to talk to machines.
Ivan SutherlandMIT Lincoln Laboratory, Massachusetts
For his PhD, Sutherland wrote Sketchpad on the TX-2 computer. You drew straight on the screen with a light pen, and the computer remembered each line as an object you could move, copy and resize.
Why it mattered. It was the first time a person drew with a computer, the seed of every modelling program since.
The skeleton battle in Jason and the Argonauts lasts a few minutes on screen but took over four months to animate, matching every sword blow to the actors.
Why it mattered. It became one of the most famous stop-motion scenes ever made.
In Jason and the Argonauts, seven skeleton puppets fight real actors with swords. Harryhausen animated them frame by frame and blended them with the live footage using his Dynamation method. The sequence took over four months to animate.
Why it mattered. It became the most famous stop-motion scene ever, and inspired a generation of film-makers.
Before animating his models, Harryhausen made dramatic key drawings of the big moments, such as a sailor fighting a skeleton in 1957. These plans led to the famous skeleton battle in Jason and the Argonauts (1963). His foundation now cares for an archive of more than 50,000 items.
Why it mattered. One strong drawing of a key moment can guide months of frame-by-frame work.
Harold Michelson drew storyboards for Hitchcock's The Birds, and worked on films such as The Ten Commandments and The Graduate. Storyboard artists like him worked out where the camera would stand for each shot. His wife, Lillian Michelson, became a celebrated film researcher.
Why it mattered. Storyboard artist had become a skilled job of its own in Hollywood.
John Cameron and James SorensonUniversity of Wisconsin, Madison, USA
Cameron and Sorenson passed a thin beam of low-energy rays from a radioactive source across a forearm bone. By counting how much got through, they could work out how much mineral the bone held, to within about 3 percent. It was called single photon absorptiometry.
Why it mattered. It was the first practical way to measure bone strength in living people.
Starzl's team tried the first human liver transplants in Denver. The patients lived no more than 23 days. Starzl paused and spent four years improving the surgery and the drugs that stop the body rejecting a new organ.
Why it mattered. The failures taught surgeons what they needed to fix before transplants could work.
Delia Derbyshire (BBC Radiophonic Workshop), from a score by Ron GrainerLondon, England
Ron Grainer wrote the tune for a new TV series called Doctor Who, and Derbyshire turned it into sound. With no synthesizer, she built every note from test oscillators and noise, shaping each swell and fade and splicing the tape by hand. It was one of the first TV themes made entirely with electronics, yet she got no screen credit for 50 years.
Why it mattered. It showed millions of viewers what electronic sound could do, years before synthesizers were in shops.
Don Buchla, with Morton Subotnick and Ramon SenderSan Francisco, USA
In 1963 two composers at the San Francisco Tape Music Center advertised for an engineer to build a new electronic instrument, and Don Buchla answered. He designed modules that made and shaped sound, joined by patch cords and played from touch plates instead of a piano keyboard. A Rockefeller Foundation grant helped pay for it, and the system was installed at the center by 1965.
Why it mattered. Buchla in the West and Moog in the East invented the modular synthesizer at almost the same time.
Walter B. Horne and Robert C. DreherNASA Langley Research Center, Virginia, USA
Testing aircraft tyres on flooded runways, NASA engineers found that above a certain speed a tyre lifts right off the ground on a wedge of water. That speed depends on the tyre pressure: about 9 × √(pressure in psi) knots.
Why it mattered. Their rule is still used for aircraft, and helps explain why worn car tyres aquaplane.
Now at Tufts, Cormack published two papers in the Journal of Applied Physics showing how to rebuild a slice from line measurements, and tested the idea with gamma rays on simple phantoms of aluminium and wood. The papers got almost no attention at the time.
Why it mattered. The theory of CT was complete before anyone built a scanner, even though Cormack did not know about Radon's work.
Satya Prakash Mathur and Madhuri MathurMumbai, Maharashtra
Madhuri Mathur's German Braun blender overheated on Indian grinding, and she asked her husband, a Siemens engineer, to fix it. Instead he designed a new mixie with a much stronger motor, and in 1963 set up a company, Power Control and Appliances, to make it, starting at about 8 mixies a month. He did the engineering, she gave the cook's view, and they called it Sumeet, Sanskrit for ‘good friend’.
Why it mattered. It was India's first mixer grinder built for chutneys, masalas and batters, and ‘mixie’ became an Indian word.
Robot-Coupe says it has made kitchen machines in France since 1961. According to Magimix, Pierre Verdun and his friend Robert Comte built a machine with a blade at the bottom of a bowl that could chop, grind, shred and knead, and launched it for professional chefs in 1963.
Why it mattered. It turned the blender into the food processor, one machine for many chopping jobs.
Engineers at General Atomics rolled flat sheets of membrane and spacer mesh around a central tube, like a Swiss roll. Water pushed in along the outside and clean water spiralled into the tube.
Why it mattered. The spiral-wound element packs a large membrane into a small tube, and it is the shape of the RO cartridge in a home purifier.
Horie developed a pen with a tip made of bundled acrylic fibres, fed by capillary action from a water-based ink reservoir. The Pentel Sign Pen became hugely popular.
Why it mattered. The ancestor of today's felt-tips, fineliners and whiteboard markers.
An amendment added Chapter IVA to the Drugs and Cosmetics Act, bringing Ayurvedic, Siddha and Unani medicines under licensing, labelling and quality rules.
Why it mattered. It is still the law that decides how Siddha medicines are made and sold.
Sharp's Compet CS-10A used 530 germanium transistors and 2,300 diodes. It weighed 25 kg and cost 535,000 yen, about as much as a car. The Friden EC-130 of 1963 was another early transistor calculator.
Why it mattered. Transistors replaced tubes, starting the race to make calculators smaller and cheaper.
Motorola's Pageboy I was a tone-only pager with no screen and no memory. When it beeped, the wearer knew to call the office or go straight to the emergency room. Some accounts date its launch as late as 1974.
Why it mattered. It began Motorola's decades as the world's biggest pager maker.
Xerox introduced Long Distance Xerography, often called the first modern commercial fax machine. It rented for about $800 a month and needed special high-speed lines.
Why it mattered. It showed business would pay to send documents instantly, not just photos.
Walt Disney asked Blair to help design the It's a Small World ride for the 1964 New York World's Fair. The finished ride closely follows her style. It was later rebuilt in Disney parks around the world.
Why it mattered. Concept art could shape real places people walk through, not only films.
R. G. Macfarlane; Earl Davie and Oscar RatnoffOxford, England and Cleveland, USA
Within weeks of each other, two teams proposed that clotting proteins work in a chain: each switched-on factor switches on many copies of the next, like a waterfall that grows as it falls. The chain ends with thrombin turning fibrinogen into fibrin.
Why it mattered. It explained how a tiny wound makes a big clot fast, and what goes wrong in haemophilia.
Amoore proposed that smell depends on molecules fitting receptor sites of certain shapes, like keys in locks, and suggested seven primary odours. He set it out for the public in Scientific American in 1964. Later he agreed there must be many more than seven kinds of receptor.
Why it mattered. He was right that shape matters, even though the real system turned out to be far bigger.
Robert Moog, with composer Herb DeutschTrumansburg and New York City, USA
Moog built modules whose pitch and loudness were set by a voltage, using one volt for each octave. Composer Herb Deutsch asked for a way to make each note swell and fade, and Moog built the envelope, first triggered by a doorbell button. Moog showed his system at the Audio Engineering Society convention in New York and, to his surprise, took orders.
Why it mattered. Voltage control let every module steer every other one, the core idea of the analog synthesizer.
More than 73 million Americans watched the Beatles play on The Ed Sullivan Show. It set a record for US television at the time. The night inspired many young viewers to pick up guitars and form bands.
Why it mattered. Two electric guitars, a bass and drums became the standard rock band.
Hodgkin used X-rays to work out the structures of penicillin and vitamin B12, molecules too complicated for others to crack. She won the 1964 Nobel Prize in Chemistry. Later she also solved the structure of insulin.
Why it mattered. Knowing a medicine's exact shape helps chemists make it and improve it.
Donald Bitzer, H. Gene Slottow and Robert WillsonUniversity of Illinois, USA
Three researchers built a plasma display for PLATO, an early computer teaching system. Each dot was a tiny cell of gas that glowed when zapped with electricity. Decades later the same idea gave the world big flat TVs.
Why it mattered. It showed that a screen could be flat, with no tube behind it.
Bosch started work on a home dishwasher in 1960, showed its first one at a trade fair in 1964, and began mass production in March 1965. Bosch says machines of the 1960s used about 60 litres of water and 2.3 kWh of electricity for each wash.
Why it mattered. Dishwashers became a mass-produced European appliance, and the race to use less water began.
Alexey Ivakhnenko and Valentin LapaKyiv, Ukrainian SSR (now Ukraine)
At the Institute of Cybernetics in Kyiv, Alexey Ivakhnenko and Valentin Lapa trained networks with several layers, adding and pruning one layer at a time. Their method was called the Group Method of Data Handling. By 1971 Ivakhnenko reported a network eight layers deep.
Why it mattered. It is often called the first working deep learning, decades before the word existed.
In a magazine article, Gordon Moore noticed that the number of parts on a chip was doubling every year, and guessed it would continue. In 1975 he changed his estimate to doubling about every two years.
Why it mattered. The prediction became a target the whole chip industry raced to hit for 50 years.
The No. 1 Electronic Switching System was the first big exchange controlled by a stored program, like a computer. New services could be added by changing software instead of rewiring.
Why it mattered. Exchanges became computers, which made features like call waiting and call forwarding possible.
Texas Instruments invented the thermal print head in 1965. Its Silent 700 terminal of 1969 printed on heat-sensitive paper with no ink at all, and became the first commercial thermal printing system.
Why it mattered. The same idea prints nearly every shop receipt and bus ticket today.
Film laboratory colour timersHollywood, USA, and labs worldwide
In a film lab, a colour timer set how much red, green and blue light printed each scene, in steps called printer points from 1 to 50. From about the mid-1960s, timers used a Hazeltine colour analyser: a screen that showed a positive picture from the negative. Their choices were punched onto paper tape that ran the printer.
Why it mattered. Balancing red, green and blue shot by shot is still the heart of grading today.
Ray Dolby founded Dolby Laboratories and built his A-type noise reduction for recording studios. It boosted quiet sounds before recording and lowered them again on playback, pushing tape hiss far down.
Why it mattered. Cleaner tracks let film sound get richer and louder without drowning in noise.
The Swedish photographer Lennart Nilsson spent years taking pictures of human embryos and fetuses with special cameras and lenses. Life magazine printed them as Drama of Life Before Birth, and millions of copies sold within days.
Why it mattered. For many people it was the first time they saw how a baby develops.
Niu Jingyi, Wang You, Xing Qiyi, Zou Chenglu and teamsShanghai and Beijing, China
Teams of Chinese chemists joined amino acids one by one to build both chains of insulin, then joined the chains together. The result formed crystals and worked just like natural insulin. It was the first protein ever made fully in a lab.
Why it mattered. It showed that a hormone is just a molecule that chemists can build.
Ebashi discovered troponin, the protein on actin that grabs calcium and moves tropomyosin out of the way so myosin can bind. It explained how calcium turns muscle on and off.
Why it mattered. It completed the chain from nerve signal to calcium to cross-bridge.
Urist found that bone with its minerals removed, placed in muscle, could make new bone grow there. He said something in bone tells nearby cells to turn into bone cells, and later called it bone morphogenetic protein, or BMP. Scientists, including India-born A. Hari Reddi, went on to purify these proteins.
Why it mattered. It opened the way to proteins that help broken bones and spines fuse.
Blumberg was studying how people's blood proteins differ when he found a strange protein in the blood of an Aboriginal Australian man. He called it the Australia antigen. Over the next few years he showed it was part of the virus that causes hepatitis B, and in 1976 he shared the Nobel Prize for this work.
Why it mattered. It led to a blood test for hepatitis B and then to a vaccine.
Lloyd Beidler and Richard SmallmanFlorida State University, USA
By labelling new cells in rats, Beidler and Smallman showed that taste-bud cells are constantly replaced, living about ten days on average before new ones take their place.
Why it mattered. It explains why taste usually recovers after a burn from hot food or drink.
All India Institute of Speech and Hearing (AIISH)Mysuru
AIISH began in 1965 as the Institute of Logopedics on the Manasagangotri campus in Mysuru. It trains audiologists and speech therapists and runs hearing clinics and research, under India's health ministry.
Why it mattered. It built much of India's audiology profession.
Pandit Kishan Maharaj (1923–2008)Edinburgh and London, UK
Kishan Maharaj of Benares was famous for dazzling cross-rhythms and endings called tihais. In 1965 he played at the Edinburgh Festival and the Commonwealth Arts Festival in Britain. India later gave him the Padma Vibhushan, one of its highest civilian honours, in 2002.
Why it mattered. He helped take the grand Benares style to audiences outside India.
Indian Oil released the first Indane LPG connection in Kolkata. It started with two dealers, in Kolkata and Patna, and about 2,000 customers, many of them nervous about keeping a gas cylinder at home.
Why it mattered. Indane grew into one of the biggest LPG brands in the world, serving more than 13 crore Indian families.
Sidney Loeb and the city of CoalingaCoalinga, California, USA
Coalinga's well water was too full of minerals to drink, so drinking water was brought in by railway tank cars. A small plant with Loeb's membranes began turning the salty well water into drinking water, about 5,000 gallons a day.
Why it mattered. It was the first reverse osmosis plant to make drinking water for a town.
Fisher patented a ballpoint refill sealed with nitrogen at about 35 psi behind the ink. The gas pushes on the ink from behind, so the pen writes upside down, underwater or in space; NASA astronauts used it from 1968.
Why it mattered. Gas pressure pressing evenly on a liquid, Pascal's idea in a pocket.
Koichi Kawai, who had learned from Torakusu Yamaha, founded his own piano company in Hamamatsu in 1927. After the war both firms grew fast, and by 1965 Yamaha was making more pianos than any other maker in the world. In 1970 it built its millionth piano.
Why it mattered. Careful factory methods made good pianos affordable for millions of families.
Harold Rhodes, Fender and Robert MoogCalifornia and New York, USA
During the Second World War Harold Rhodes made small pianos for injured airmen to play in bed. His tines, struck by hammers and read by pickups, led to the Fender Rhodes electric piano in 1965; Wurlitzer's used steel reeds instead. In 1964 Robert Moog built his first synthesizer.
Why it mattered. Electric keyboards were light, loud enough for bands and gave jazz, soul and pop a new sound.
Fisher patented a sealed refill with pressurised nitrogen behind the ink, so it writes upside down, underwater and in weightlessness. Astronauts used it from Apollo 7 in 1968. The popular tale that NASA spent millions on it while Soviet cosmonauts used pencils is a myth: Fisher paid for its development.
Why it mattered. It solved the ballpoint's dependence on gravity.
Seymour Papert and studentsMIT Artificial Intelligence Group, Cambridge, United States
A memo from MIT planned a summer project for students to build a large part of a visual system, including telling objects from the background and naming them. It turned out to be far harder than anyone expected.
Why it mattered. It became a famous lesson: seeing feels effortless to people, but getting a computer to do it took decades.
ELIZA matched keywords in what you typed and replied from simple scripts, most famously as a therapist who turned your words into questions. It learned nothing. Yet many users felt understood, which alarmed its creator.
Why it mattered. The "ELIZA effect", trusting fluent text too much, is still the key caution with LLMs.
Samarendra Kumar Mitra and Jnan Saran ChatterjeeIndian Statistical Institute and Jadavpur University, Calcutta (now Kolkata)
Engineers from the Indian Statistical Institute and Jadavpur University built ISIJU-1, a computer made with transistors instead of vacuum tubes. It was working by about 1964 and was formally commissioned on 2 April 1966.
Why it mattered. It was India's first solid-state digital computer.
Albert Gordon, Andrew Huxley and Fred JulianLondon
By holding single frog fibres at different lengths, they showed that force is greatest when actin and myosin overlap most, and falls when the fibre is stretched or squashed.
Why it mattered. It is the length–tension curve in chapter 3, and strong proof of sliding filaments.
Bergström revived Duchenne's idea of a biopsy needle and used it on athletes. With Hultman he showed that muscle glycogen runs down in long exercise and that a high-carbohydrate diet refills it, the start of "carb loading".
Why it mattered. Sports science could now measure fuel and fibre types in living people.
James Cimino, Michael Brescia and colleaguesNew York
Surgeons joined an artery straight to a vein in the forearm. The vein grows big and strong, so it can be used for dialysis again and again without a tube left in the skin.
Why it mattered. The fistula is still the preferred way into the blood for haemodialysis.
Pete Conrad and Richard Gordon, Gemini 11Earth orbit
The Gemini 11 crew tied their capsule to an Agena rocket with a 30 m tether and fired thrusters to set the pair slowly turning like a bola. It made about 0.00015 g, the first artificial gravity created in space.
Why it mattered. It showed spinning spacecraft could make gravity, though a useful amount needs a big, fast ring.
Charles Gros and the CGR companyStrasbourg, France
Breast tissue is soft, so ordinary X-rays show little inside it. In the United States, Robert Egan had shown how gentle, low-energy X-rays and fine-grained film could reveal small tumours. Gros designed the Senographe, the first machine made only for mammography, with a molybdenum target and a paddle that presses the breast flat.
Why it mattered. Mammography now finds breast cancers early, when they are easiest to treat.
Charles Kao and George HockhamStandard Telecommunication Laboratories, Harlow
Glass fibres of the time lost almost all their light within a few metres, around 1,000 dB per kilometre. Kao and Hockham worked out that the loss came from impurities, not from glass itself, and that pure glass could get below 20 dB per kilometre, enough for telephone lines.
Why it mattered. It started the race to make optical fibre, and won Kao the Nobel Prize in Physics in 2009.
Sharp's R-600 put the food on a spinning plate. Microwaves bounce around the box and leave hot and cold spots, so turning the food spreads the heat more evenly. American ovens instead used a spinning metal stirrer in the roof.
Why it mattered. The turntable became the standard design found in most microwave ovens today.
By measuring blood going into and out of the brain of fasting volunteers, the team showed that after several weeks ketones made from fat supply most of the brain's fuel.
Why it mattered. It explained how people survive long fasts, and why fasting shifts the body onto fat.
Jack Kilby, Jerry Merryman and James Van Tassel, Texas InstrumentsDallas, USA
Texas Instruments built a battery-powered prototype, code-named Cal Tech, about 4 × 6 × 2 inches and 45 ounces, with its logic on a few integrated circuits. It printed answers on paper tape. The team applied for a patent in September 1967.
Why it mattered. It proved a whole calculator could be built from chips and held in the hand.
With better surgery and a new mix of anti-rejection drugs, Starzl's team transplanted livers into several children in 1967, and this time they survived the operation and went home. It was the first time a liver transplant had truly worked.
Why it mattered. Liver transplants now save tens of thousands of lives around the world every year.
George Wald, Ragnar Granit and Haldan Keffer HartlineHarvard, Stockholm and Rockefeller University
Wald showed that vitamin A forms retinal, the part of rhodopsin that changes shape when it catches light. Granit and Hartline showed how the retina's cells turn light into nerve signals.
Why it mattered. It explained the first step of vision, from photon to signal.
Christiaan BarnardGroote Schuur Hospital, Cape Town, South Africa
Barnard's team gave Louis Washkansky, a 53-year-old grocer, the heart of Denise Darvall, a young woman killed in a car crash. The new heart was started with an electric shock and worked well. Washkansky died of pneumonia 18 days later, because the drugs that stopped rejection also weakened his defences.
Why it mattered. It showed a heart could be moved from one person to another and work.
Chowning, a music student at Stanford, found that wobbling the pitch of one tone very fast with another creates a rich new sound. He published the idea in 1973, and a US patent (4,018,121) was granted in 1977. Stanford licensed it to Yamaha in Japan.
Why it mattered. FM builds bright, bell-like sounds from just two simple waves, cheaply enough to fit on a computer chip.
George Harrison with musicians of the Asian Music Circle, including Natwar SoniAbbey Road Studios, London
George Harrison recorded 'Within You Without You' for the Beatles album Sgt. Pepper's Lonely Hearts Club Band. Indian musicians from London's Asian Music Circle played dilruba, swarmandal and tabla. The tabla player, Natwar Soni, was only publicly identified decades later.
Why it mattered. Millions of rock fans heard the tabla on one of the best-known albums ever made.
Ustad Alla Rakha with Ravi ShankarMonterey, California
At the Monterey International Pop Festival, Ravi Shankar played sitar with Alla Rakha on tabla. Alla Rakha's fast, fiery solo thrilled a crowd of rock fans, and the live album became Shankar's best-selling record. Two years later, on 15 August 1969, they played Woodstock in the pouring rain.
Why it mattered. It made the tabla famous with a whole new generation in the West.
INS Kalvari, a Soviet-built Foxtrot-class diesel submarine, joined the Indian Navy on 8 December 1967. India marks the date as Submarine Day. A new Kalvari, of the Scorpène class, was commissioned in 2017.
Why it mattered. It began India's own submarine service.
Brij Bhushan Kabra discovered the Hawaiian slide guitar in Kolkata and promised his father he would play only classical music on it. He added drone and sympathetic strings, and became the first Indian musician to play ragas on the guitar. In 1967 he recorded Call of the Valley with Shivkumar Sharma and Hariprasad Chaurasia.
Why it mattered. Call of the Valley became one of the best-selling Indian music albums worldwide and made the guitar a classical Indian instrument.
Simon Prebble, Scientific Demonstrations LtdLondon, England
English actor Simon Prebble named the wooden desk toy made by his company 'Newton's cradle'. Chrome versions soon became an office classic. The idea itself went back to Mariotte, three centuries earlier.
Why it mattered. Momentum and energy conservation on millions of desks.
India published IS 4250, its standard for domestic electric food mixers (liquidizers and grinders), in 1967 and revised it in 1980. It checks that a mixer does not get too hot, does not give shocks and survives 96 hours of running. One of its tests is very Indian: the mixer must grind rice and black gram into idli batter.
Why it mattered. It gave buyers a way to trust a mixer, through the ISI mark.
Veselago asked what would happen in a material where both the electric and the magnetic response were negative. He showed that light would bend the wrong way at the surface, to the same side of the normal, as if the refractive index in Snell's law were negative. No such material existed, so the idea sat quietly for thirty years.
Why it mattered. It opened the door to materials whose optical properties come from their structure, not their chemistry.
Raytheon bought the appliance maker Amana in 1965, and in 1967 it launched a Radarange small enough for the kitchen counter that plugged into an ordinary wall socket. It cost $495, still a lot of money. A cheap magnetron, developed with Raytheon's Japanese partner New Japan Radio, helped bring the price down.
Why it mattered. It is widely considered the first popular home microwave oven.
Shinshu Seiki launched the EP-101, a tiny electronic printer only 16 cm wide that was soon built into desk calculators. Later printers based on it were sold as the "son of EP", which is where the name Epson comes from.
Why it mattered. It showed that a printer could be small and cheap enough to go inside other machines.
A feature film used to come on several reels, so cinemas needed two projectors and a quick changeover. Big flat platters let the whole film lie spliced together on one turntable, feeding the projector from the middle and winding back on another. The German cinema owner Willi Burth is credited with the idea, and Kinoton sold its ST 200 platter from about 1968.
Why it mattered. No rewinding and no changeovers meant one projectionist could run many screens, which helped make multiplexes possible.
Stanley Kubrick, editor Ray LovejoyBorehamwood, England
In 2001: A Space Odyssey, an early human throws a bone into the air, and a match cut turns it into a satellite in orbit, jumping millions of years in one frame.
Why it mattered. It showed how a single match cut can carry a huge leap in time and meaning.
Stanley Kubrick and his effects teamElstree Studios, England, UK
For the 'Dawn of Man' scenes of 2001: A Space Odyssey, photographs of African landscapes were front-projected onto a giant Scotchlite screen behind actors in ape costumes. The modern version of front projection was fully developed for this film.
Why it mattered. It proved a whole landscape could be put behind actors on a stage, sharp and bright.
Arthur Appel, IBMUSA (AFIPS Spring Joint Computer Conference)
Appel described sending an imaginary ray from the eye through each point of the picture to find which surface it hits first. He then sent a second ray towards the light to check whether that spot sat in shadow. It is widely considered the first published work on ray casting for computer pictures.
Why it mattered. One ray per pixel is still the heart of every ray tracer today.
Pati studied puppet animation under Jiří Trnka in Prague and became head of animation at Films Division. His experimental short films of the late 1960s, such as Explorer (1968), mixed live action with techniques like pixilation.
Why it mattered. He brought European puppet and stop-motion ideas into Indian government film-making.
Stanley Kubrick; Vickers-Armstrong EngineeringMGM-British Studios, Borehamwood
For 2001: A Space Odyssey, engineers built a real rotating wheel about 38 feet across and weighing around 30 tons. Actors walked at the bottom while the wheel turned, so they seemed to run all the way round the ship. It cost about 750,000 dollars.
Why it mattered. It made fake gravity look real by actually turning the whole set.
Ram Chandra Sharma and Dr P. K. SethiJaipur, Rajasthan, India
Western artificial feet were costly and did not let people squat, sit cross-legged or walk barefoot in fields. Craftsman Ram Chandra Sharma and surgeon P. K. Sethi made a flexible foot from wood, rubber and tyre-cord. Through the charity BMVSS it is fitted free, and has helped over 2.5 million people.
Why it mattered. It showed a cheap, clever design can give millions of people their walk back.
Norbert Hirschhorn, Nathaniel Pierce, David Nalin, Richard Cash and colleaguesDhaka (then East Pakistan) and Kolkata, India
Trials showed that even people with severe cholera can absorb a drink of glucose, salt and water, because sugar carries sodium, and water follows, into the gut wall. It cut the need for drips by about 80%.
Why it mattered. It turned rehydration from a hospital job into something a parent can do.
Studying haemoglobin in Tehran, the Iranian scientist Samuel Rahbar found an unusual form that was raised in people with diabetes. It was later named HbA1c: haemoglobin with glucose attached.
Why it mattered. HbA1c became the test that shows average blood sugar over about three months.
David Nalin, Richard Cash, Norbert Hirschhorn, Nathaniel Pierce, Rafiqul Islam, A. Majid Molla and othersDhaka, then East Pakistan, and Calcutta (Kolkata), India
Cholera can drain a person of litres of water a day, and the treatment was a drip into a vein. Teams at the Cholera Research Laboratory in Dhaka and the Johns Hopkins centre in Calcutta tested drinks of glucose and salt. In 1968 Nalin and Cash showed that such a drink cut the need for drip fluid by about 80 percent.
Why it mattered. It proved the gut can keep absorbing water during cholera if you give it sugar and salt together.
Wendy Carlos, with producer Rachel ElkindNew York City, USA
Carlos recorded music by Johann Sebastian Bach on a Moog synthesizer, layering the parts one line at a time on tape. The album reached the top 10 of the US Billboard chart and won three Grammy Awards in 1970. It sold more than a million copies and became the first classical album certified platinum.
Why it mattered. It convinced the world that a synthesizer could be a serious, beautiful instrument, not just a noise box.
John W. ColtmanWestinghouse Research Laboratories, Pittsburgh, USA
John Coltman, a physicist and keen flute player, measured what happens when a jet of air hits the far edge of a flute's mouth hole. He showed that waves travel along the jet, and the time they take to reach the edge helps decide which note sounds and how loud. Blowing faster lets the jet match a higher note, which is why flautists blow harder for the upper octave.
Why it mattered. It explained the edge tone, the heart of every flute, from bone flutes to the bansuri.
Godfrey HounsfieldEMI Central Research Laboratories, Hayes
Hounsfield, an engineer who had built one of Britain's first all-transistor computers, had the idea of scanning a body from many angles and letting a computer rebuild it. His lab prototype, with a gamma-ray source, took up to nine days to collect the data for one slice and over two hours of computing to rebuild it. He tested it on preserved brains, then on cattle brains.
Why it mattered. It proved that a computer could turn shadows into a slice with enough detail to tell grey matter from white.
George Heilmeier and team, RCAPrinceton, New Jersey, USA
RCA showed the first liquid crystal displays at a press conference in New York. A small voltage changed how the crystals handled light. The team predicted flat screens would one day replace bulky picture tubes.
Why it mattered. It was the first step toward the LCD in most TVs sold today.
Willard Boyle and George SmithBell Labs, Murray Hill, United States
Boyle and Smith invented the charge-coupled device (CCD), a chip that stores light as packets of electric charge and reads them out pixel by pixel. It became the eye of digital cameras and telescopes.
Why it mattered. Cheap image sensors made digital pictures, and so computer vision, part of everyday life. They shared the 2009 Nobel Prize in Physics.
Marvin Minsky and Seymour PapertMIT, Cambridge, United States
Two MIT researchers published a careful mathematical book showing what a single-layer perceptron cannot do. One famous example: it cannot learn XOR, "one or the other but not both". Multilayer networks could, but nobody yet knew a good way to train them.
Why it mattered. The book helped push funding and interest away from neural networks for more than a decade.
S. Srikantan and team, BARC and ECILTrombay (Bombay) and Hyderabad
A prototype 12-bit computer, the TDC-12, was completed in 1969 and made by the new public company ECIL. About 20 had been supplied by 1971, for jobs like watching for earthquakes. ECIL went on to make the 16-bit TDC-316 and, in 1979, the 32-bit System 332.
Why it mattered. India began making computers in a factory, not just in a lab.
Make-up artist John Chambers designed the ape faces for Planet of the Apes, letting actors speak and show emotion through the rubber. There was no make-up Oscar yet, so the Academy gave him an honorary award.
Why it mattered. It showed that make-up effects deserved their own prize, which came in 1982.
German television asked Osram for a safer, cleaner replacement for carbon arcs. Osram's HMI lamp, a metal-halide arc, went on sale as a 575 W model in 1969 and was widely used for TV at the 1972 Munich Olympics. It gives light close to daylight, about 5,600 to 6,000 K, and roughly four times as much light per watt as a tungsten bulb.
Why it mattered. HMIs let crews match or beat the sun on location, and they replaced carbon arcs.
Ray kept a red cloth notebook, a kheror khata, for each film. It held notes, sketches, music and storyboards. The one for Goopy Gyne Bagha Byne (1969) has been digitised with its sketchbook for anyone to explore.
Why it mattered. It shows one artist planning a whole fantasy film by hand, page by page.
For his later films Ray planned everything in red cloth-bound notebooks he called his kheror khata, the kind Bengali account-keepers used. They hold story ideas, character and set drawings, shooting scripts, storyboards and music. The first notebook for Goopy Gyne Bagha Byne (1969) alone runs to 733 pages.
Why it mattered. They show a screenplay and a storyboard living side by side in one book.
William Wolff and Hiromi ShinyaBeth Israel Medical Center, New York
Using a long fibre-optic colonoscope made in Japan, the surgeons Wolff and Shinya examined the whole colon. Three months later Shinya used a wire snare he designed to remove a polyp through the scope.
Why it mattered. Finding and removing polyps early is how colonoscopy prevents colon cancer.
Dorothy Crowfoot HodgkinUniversity of Oxford, England
Using X-ray crystallography, Dorothy Hodgkin and her team solved the 3D structure of insulin, 34 years after her first X-ray photo of it. She had already won the 1964 Nobel Prize in Chemistry for other structures.
Why it mattered. Seeing insulin's shape helped explain how it works and how to design new versions.
Joseph Szurszewski; Gaston Vantrappen and colleaguesMayo Clinic, USA, and Leuven, Belgium
Szurszewski found that between meals, a strong band of squeezing sweeps slowly down a fasting dog's small intestine, again and again. Eating stops it. In 1977 Vantrappen's team found the same pattern in people, and that it was missing in some patients with too many bacteria in the small intestine.
Why it mattered. This migrating motor complex acts as the gut's housekeeper, and may be part of why your tummy rumbles when you are hungry.
Gita Sarabhai and the National Institute of DesignAhmedabad, India
A Moog modular synthesizer arrived at the National Institute of Design in Ahmedabad for its new electronic music studio. The musician Gita Sarabhai, who had studied with John Cage in the US, used her New York connections to bring it to India. The American composer David Tudor guided the new studio.
Why it mattered. It was one of the earliest synthesizers in India, a sign that the new sound was spreading around the world.
Honda's CB750 had four cylinders, electric starting and a hydraulic disc brake on the front wheel, at a price many riders could afford. Magazines called it the first 'superbike'.
Why it mattered. It helped make disc brakes normal on motorcycles, and Japanese bikes the world's favourite.
A popular story says Beatles record sales paid for the CT scanner. Historians doubt it: a 2012 study estimated that EMI spent about £100,000 on the project (not counting salaries), while the UK Department of Health and Social Security spent about £606,000 and agreed early to buy scanners. EMI's music profits may have helped the company afford research, but the exact link is disputed.
Why it mattered. It's a reminder that big medical inventions often rest on public money as well as private.
Stove makers in Europe, Japan and the USAWorldwide
From about the mid-1960s, piezo igniters moved from lighters into gas appliances; an Austrian patent for a gas stove with one was filed in 1969. Stoves also gained flame failure devices: a thermocouple in the flame holds the gas valve open, and if the flame blows out it cools and the valve snaps shut.
Why it mattered. No more matches, and far less danger of unburned gas filling the kitchen.
Fuji Electric built a 200 kVA power supply with a large three-phase thyristor inverter and delivered it to a Fujitsu computer plant. It had no spinning flywheel, so it was smaller and could go almost anywhere. Static UPS systems like this spread to guard mainframe computers around the world.
Why it mattered. Battery, charger and thyristor inverter together made the modern static UPS.
The Act set up the Central Council of Indian Medicine (1971) to regulate education and practice in Ayurveda, Siddha and Unani, including registration of practitioners.
Why it mattered. Siddha doctors gained a national register and minimum standards for colleges.
The Indian Medicine Central Council Act set up the Central Council of Indian Medicine to regulate the education and practice of Ayurveda, Siddha and Unani.
Why it mattered. It made Unani a regulated profession with recognised degrees such as BUMS.
The Act created the Central Council of Indian Medicine to set standards for Ayurveda, Siddha and Unani education and to keep a central register of qualified practitioners.
Why it mattered. It made BAMS a regulated degree with national standards.
In his master's thesis, Finnish student Seppo Linnainmaa described reverse-mode automatic differentiation. It works backwards through a long chain of sums to find how much each step affected the final answer.
Why it mattered. It is the maths at the heart of backpropagation, although he was not thinking about neural networks.
Centronics, led by Robert HowardHudson, New Hampshire, USA
The Centronics 101, shown in 1970, printed 165 characters a second by firing a column of seven wire pins through a ribbon. Its plug became the standard printer connector for decades. Japan's OKI had shown a wire dot printer a little earlier, in 1968.
Why it mattered. Dot-matrix printers were how most computer users printed for twenty years, and they still print passbooks and forms.
Graeme Ferguson, Roman Kroitor, Robert Kerr and William ShawFuji Group Pavilion, Expo '70, Osaka
A team from Canada showed the first IMAX film, Tiger Child, at the Fuji Group Pavilion in Osaka. IMAX film runs sideways, and each frame is 15 perforations wide on 70 mm film, about ten times the area of a normal 35 mm frame. The first permanent IMAX cinema, the Cinesphere in Toronto, opened in 1971.
Why it mattered. It showed that a bigger frame could fill your whole view, the idea behind every giant screen since.
Pathak founded the Sulabh movement and spread a cheap two-pit pour-flush toilet that needs no sewer: one pit fills while the other turns safely into manure. Sulabh went on to build over a million household toilets.
Why it mattered. It helped end manual scavenging and showed that clean toilets can be affordable.
Bill Hemsath, Robert Moog and the Moog teamTrumansburg, New York, USA
Engineer Bill Hemsath sawed a keyboard in half and wired a few spare modules into a small box. That became the Minimoog: three oscillators, a filter and envelopes, already connected so there were no cables to patch. It was one of the first synthesizers sold in ordinary music shops, and more than 12,000 were made.
Why it mattered. It took the synthesizer out of the studio and onto the stage, and its layout is still the classic synth.
Martin Schadt and Wolfgang Helfrich; James FergasonBasel, Switzerland; Kent, Ohio, USA
Schadt and Helfrich at Hoffmann-La Roche filed a patent on 4 December 1970 for a twisted layer of liquid crystal between two polarising filters. Fergason in the US patented the same idea in 1971, and the rivals later shared the royalties. The twist lets each cell act as a tiny light shutter that needs very little power.
Why it mattered. Almost every LCD for decades was built on this twisted-nematic trick.
Robert Maurer, Donald Keck and Peter SchultzCorning Glass Works, New York
The Corning team made fibre from very pure silica glass built up from vapour, with a core a little denser than the glass around it. Keck measured a loss of about 17 dB per kilometre and wrote "Whoopee!" in his notebook. By 1972 they had reached 4 dB per kilometre.
Why it mattered. It beat Kao's target and made fibre-optic communication practical.
During the Bangladesh war, cholera broke out among refugees at Bangaon and intravenous fluid ran out. Dr Dilip Mahalanabis’s team gave oral rehydration solution, water with glucose and salt, by the bucket. Deaths fell to about 3.6%, where about 30% had been expected.
Why it mattered. ORS has since saved tens of millions of children; The Lancet called it potentially the most important medical advance of the century.
Federico Faggin, Ted Hoff, Stanley Mazor and Masatoshi ShimaIntel, Santa Clara, California
The Intel 4004 put a whole processor on one chip, with about 2,300 transistors running at up to 740 kHz. It was first designed for a Japanese company's calculator. It is widely called the first commercial microprocessor.
Why it mattered. Every phone and laptop today has descendants of this chip at its heart.
Masatoshi Shima (Busicom), Federico Faggin, Ted Hoff and Stan Mazor (Intel)Santa Clara, USA and Japan
The Japanese company Busicom asked Intel for chips for its 141-PF printing calculator. Intel's team put the calculator's processor on one chip, the 4004, with 2,300 transistors, running at up to 740 kHz. It was announced on 15 November 1971.
Why it mattered. The first commercial microprocessor was made for a calculator, which is why calculators are the stepping stone to computers.
Gary StarkweatherXerox, Webster, New York, and Xerox PARC, California, USA
In 1969 Starkweather, an optics engineer at Xerox, had the idea of drawing on a copier's drum with a laser instead of a photo of a page. He moved to Xerox PARC in 1971 and built a working laser printer there, which later became the Xerox 9700.
Why it mattered. It let a computer draw any page, letters or pictures, at high speed.
Ron Jones and William ShawBrisbane, Australia, and Toronto, Canada
IMAX film is so large that a claw would tear it. The Australian machinist Ron Jones had invented a rolling loop that moves film in a gentle wave, and William Shaw adapted it for IMAX. A blast of air holds each frame flat against the lens while it is shown.
Why it mattered. It let huge, heavy film move steadily enough to show sharp pictures on a screen many storeys high.
The CMX 600 stored video on disk drives the size of washing machines, holding about half an hour of footage, and let editors jump to any shot instantly.
Why it mattered. It was the first step towards editing on computers, where you can change any cut without re-splicing everything after it.
Henri GouraudUniversity of Utah, Salt Lake City, USA
Curved objects in a computer are built from many flat pieces, so early pictures looked like cut gems. Gouraud, a French student at Utah, worked out the brightness at the corners of each piece and blended it smoothly across. He published the method in his thesis and in a 1971 journal paper.
Why it mattered. Blending across flat pieces made curved shapes look curved, cheaply enough for early hardware.
Andrew Schally and Roger Guillemin (separate teams)New Orleans and La Jolla, USA
Working with extracts from hundreds of thousands of pig and sheep brains, Andrew Schally's team worked out the structure of GnRH, the hypothalamus hormone that tells the pituitary to release LH and FSH. Roger Guillemin's team confirmed it. They shared the 1977 Nobel Prize with Rosalyn Yalow.
Why it mattered. It explained how the brain switches on puberty and runs the menstrual cycle.
Roger Guillemin and Andrew SchallyHouston and New Orleans, USA
Harris had predicted the hypothalamus sends chemical signals to the pituitary. Two rival teams ground up millions of sheep and pig brains to find them. In 1969 they found TRH, which tells the pituitary to wake up the thyroid, and in 1971 Schally's team found GnRH, which controls puberty and fertility.
Why it mattered. The brain's releasing hormones sit at the very top of the hormone chain, and both men shared the 1977 Nobel Prize.
Lymn and Taylor timed each chemical step: ATP binding frees myosin from actin, splitting ATP re-cocks the head, and releasing the products drives the power stroke.
Why it mattered. It explains why no ATP means rigor mortis.
During the Bangladesh war, drips ran out in camps where cholera spread. Mahalanabis's team gave oral rehydration solution to more than 3,000 patients; deaths fell to about 3.6%, against about 30% with drips alone.
Why it mattered. It proved ORS works in the hardest conditions, and the world took notice.
During the Bangladesh Liberation War, cholera broke out in refugee camps and drips ran short. The Kolkata doctor Dilip Mahalanabis and his team handed out packets of salt, sugar and baking soda to mix with water. About 3.6 percent of about 3,700 patients died, against about 30 percent usually.
Why it mattered. It proved oral rehydration works in a real disaster, and ORS has since saved millions of lives.
Burkitt, a surgeon who had worked in Uganda, noticed that bowel cancer and other bowel diseases were rare in rural Africa. Gathering reports from rural hospitals in Africa and India, he suggested that fibre-rich food, which makes bigger, faster-moving stools, might protect the bowel.
Why it mattered. It started decades of research linking fibre to gut health.
Mohan Rao and K. V. JohnyChristian Medical College, Vellore
Seventeen years after Boston, a team led by surgeon Mohan Rao and nephrologist K. V. Johny carried out India's first successful kidney transplant, from a living donor. They worked at night after normal hours and had prepared two donor-recipient pairs.
Why it mattered. It started kidney transplantation in India, now one of the largest programmes in the world.
Prof. M. Viswanathan, often called the father of diabetology in India, had set up a hospital in Chennai in 1954. In 1971 it became a hospital only for diabetes care, and a research centre followed in 1972.
Why it mattered. It helped make diabetes a specialty in India, decades before the scale of the problem was measured.
During the Bangladesh Liberation War, millions fled to India and cholera broke out in the camps. With drips running out, the Kolkata doctor Dilip Mahalanabis and his team gave packets of salt, sugar and baking soda to mix with water, handed out even by people with no medical training. Among about 3,700 patients treated, 3.6 percent died, compared with around 30 percent before.
Why it mattered. It proved oral rehydration works in a real disaster, not just in a hospital.
Denis BurkittLondon, England (after years in Uganda)
Burkitt, a surgeon who had worked for years in Uganda, noticed that bowel cancer and other bowel diseases were rare in rural Africa. He gathered reports from well over a thousand rural hospitals in Africa and India. In 1971 he suggested that fibre-rich food, which makes bigger, faster-moving stools, might protect the bowel.
Why it mattered. It started decades of research into how fibre and gut health are linked.
Russell and Hills; Leitereg and colleaguesUnited States
Two teams showed that the two mirror-image forms of carvone smell different: one of spearmint, the other of caraway. The molecules have exactly the same atoms, arranged as left and right hands.
Why it mattered. It proved that the nose reads a molecule’s 3D shape, not just what it is made of.
Alan R. Pearlman and Dennis Colin (ARP Instruments)Massachusetts, USA
The ARP 2600 came with its parts already wired together, but you could reroute them with patch cords. That made it a favourite for teaching in schools and colleges. Sound designer Ben Burtt used one, mixed with his own voice, to make the beeps and whistles of R2-D2 in Star Wars.
Why it mattered. Semi-modular design let beginners hear a sound first, then learn by rewiring it.
All India Radio and the Sangeet Natak AkademiNew Delhi, India
After a 1970 meeting of music experts, All India Radio allowed top grade singers and qawwali groups to use the harmonium as an accompaniment. Solo harmonium recitals stayed off its main music programmes for many years after. One critic argued the harmonium should not be treated as an untouchable.
Why it mattered. The harmonium was back on air, but still not trusted as a solo instrument.
Damadian reported that the nuclear magnetic resonance signal of some tumours fades more slowly than that of healthy tissue, and proposed using it to find cancer. On 3 July 1977 his team made the first scan of a whole human body with their magnet, 'Indomitable'.
Why it mattered. It was the first push to use magnetic resonance in medicine.
14th General Conference on Weights and MeasuresParis, France
The world's measurement conference gave the unit of pressure, one newton per square metre, a name of its own: the pascal. One pascal is tiny, about the pressure of a sheet of paper lying flat on a table. Air at sea level presses with about 101,325 pascals.
Why it mattered. P = F ÷ A got one worldwide unit, honouring the man who sent a barometer up a mountain.
Standing on the airless Moon, astronaut David Scott dropped a geological hammer and a falcon feather at the same moment. They hit the ground together, live on television.
Why it mattered. It settled Aristotle's question in front of millions: without air, mass doesn't change how things fall.
At the State University of New York Downstate, Damadian reported in Science that tumours in rats had longer NMR relaxation times than healthy tissue. He proposed using NMR to detect cancer and patented a scanning idea, granted in 1974.
Why it mattered. It pointed NMR towards medicine and showed that T1 and T2 could reveal disease.
Godfrey Hounsfield and James AmbroseAtkinson Morley's Hospital, Wimbledon, London
A woman with a suspected brain tumour became the first person scanned. The scan took about 30 minutes; the tapes were then carried across London for about two and a half hours of computing, and the picture was photographed off a screen. It showed a cyst-like mass about the size of a plum in her left frontal lobe.
Why it mattered. For the first time, doctors could see soft tissue inside a living skull without surgery or painful older tests.
G. N. Ramachandran and A. V. LakshminarayananIndian Institute of Science, Bangalore
Working on 3D images from X-ray and electron-microscope pictures, the two scientists published a way to rebuild slices by convolution: sharpen each projection with a simple filter, then back-project. It was about 30 times faster than the Fourier method. Their filter is still called Ram-Lak.
Why it mattered. Filtered back-projection became the standard way CT images were made for decades.
Godfrey Hounsfield and James AmbroseAtkinson Morley's Hospital, London, England
Hounsfield, an engineer at EMI, built a scanner that took X-rays from many angles around the head and let a computer build a slice picture. The first patient scanned had a brain tumour, which showed up clearly. Hounsfield shared the 1979 Nobel Prize with Allan Cormack, a South African-born physicist who had worked out the maths.
Why it mattered. CT showed soft organs in slices for the first time, and it changed medicine.
The German company Neff introduced its CircoTherm system, which circulated hot air around the oven so food cooked more evenly. Fan ovens slowly became normal in European kitchens. Many cooks call them fan-assisted or convection ovens.
Why it mattered. It brought forced hot air from aeroplanes and big kitchens into ordinary homes.
Standing on the airless Moon, astronaut David Scott dropped a geologist's hammer and a falcon feather together. They hit the ground at the same moment, just as Galileo had said.
Why it mattered. Millions watched gravitational and inertial mass agree live on television.
According to Magimix, Robert Comte's wife wanted a smaller version of the chefs' machine for her own kitchen. Comte made one, and the first compact home food processor, the Magimix, was born on 1 March 1971. It reached shops in Britain in 1974.
Why it mattered. The food processor moved from restaurant kitchens into homes.
Standing on the airless Moon, astronaut David Scott dropped a hammer and a falcon feather together, live on television. They hit the ground at the same moment, as Galileo had said.
Why it mattered. Without air, heavy and light things fall together.
During the Bangladesh Liberation War, cholera broke out among refugees near the border. Intravenous fluid ran out, so Dilip Mahalanabis, a paediatrician from Kolkata, had families give a simple salt-and-glucose drink themselves. In over 3,000 patients deaths fell to about 3.6%, against about 30% among those treated the usual way.
Why it mattered. It proved that oral rehydration works on a huge scale, in the worst conditions, given by ordinary people.
Westinghouse, team led by Bill Moreland and Terry MalarkeyHouston, Texas, USA
Induction cooking had been patented as early as 1906, but Westinghouse showed its Cool Top induction range in 1971. A magnetic field heats the pan itself, so the glass top stays fairly cool. The 1973 model cost $1,500.
Why it mattered. Induction makes no flame and no burnt gas, one reason it is growing in Indian kitchens as a partner to the gas hob.
US Congress and the Food and Drug AdministrationWashington, USA
The Radiation Control for Health and Safety Act of 1968 let the US government set limits for products that give off radiation. From 6 October 1971, new ovens could leak no more than 1 mW per square centimetre, measured 5 cm away, and 5 mW over their whole life. Every door needs two separate interlocks that stop the microwaves the moment it opens.
Why it mattered. Clear, strict limits helped calm fears and let the microwave into millions of homes.
Toshiba, Matsushita, Hitachi and New Japan RadioJapan
After Raytheon's basic magnetron patent ran out, several Japanese companies began making magnetrons for ovens, and Japan sold 380,000 ovens in 1969 alone. In 1971 Toshiba magnetrons went into Litton ovens in the US. Over the next decade the American magnetron makers stopped, and a few Japanese firms supplied almost the whole world.
Why it mattered. Cheap, reliable Japanese magnetrons made the home microwave affordable everywhere.
Westinghouse showed its 'Cool Top' induction range. A coil under the glass makes a fast-changing field, which induces currents in the iron pan itself. The pan gets hot and the glass stays fairly cool.
Why it mattered. Heat appears right inside the pan, so induction hobs waste less energy than flames.
David Scott, Apollo 15Hadley–Apennine landing site, the Moon
Standing on the Moon, where there is no air, Scott dropped a 1.32 kg hammer and a 0.03 kg falcon feather at the same moment. They hit the ground together, live on television.
Why it mattered. It proved on another world what Galileo and Newton said: without air, gravity speeds up everything equally.
Searching old Chinese remedies for fever, Tu Youyou read a 4th-century text telling people to soak sweet wormwood in cold water. Extracting it at low temperature, her team isolated artemisinin in 1972 and tested it in patients. She won the Nobel Prize in 2015.
Why it mattered. Artemisinin drugs are now the front-line treatment for malaria, showing traditional knowledge can yield medicines once tested.
Karen Spärck JonesUniversity of Cambridge, United Kingdom
Spärck Jones proposed giving rare words more weight than common ones when matching documents to a search, an idea now called inverse document frequency.
Why it mattered. Her statistical view of words underpins search engines and fed into later word vectors.
The HP-35 was the first handheld scientific calculator, with sine, cosine, tangent, logarithms and powers. It cost $395, weighed about 260 g and used CORDIC-style shift-and-add routines. Slide rules started to disappear.
Why it mattered. It put a scientist's desk calculator in a shirt pocket.
The E10 system, developed from research at Lannion, became the first fully digital local exchange to serve customers. Voices were switched as streams of numbers in time slots.
Why it mattered. Digital switching made exchanges smaller, cheaper and far more reliable.
Ed Catmull and Fred ParkeUniversity of Utah, Salt Lake City
Catmull made a plaster cast of his left hand and drew about 350 triangles and polygons on it in ink. He measured the corners into the computer and animated the hand opening, closing and turning, shaded and smooth. Parke did the same for a human face.
Why it mattered. It was one of the first 3D animated films, and the Library of Congress later preserved it as a national treasure.
After animating at Films Division from 1956, Ram Mohan founded Ram Mohan Biographics in 1972. He made films, title sequences and ads, taught generations of animators, and co-directed Ramayana: The Legend of Prince Rama (1993) with Japanese partners. He received the Padma Shri.
Why it mattered. He built Indian animation as an industry and a craft, and is widely called its father.
Panavision, founded in 1954 to make better anamorphic lenses, spent four years building the Panaflex. It was quiet enough to record sound without a heavy soundproof box, yet light enough to put on your shoulder. Early films included Magnum Force (1973) and The Sugarland Express (1974).
Why it mattered. Filmmakers could move a full studio camera into real places and handheld shots.
Manohar Chimote worked for years to play full classical ragas as harmonium solos, with slow openings and fast strokes like a sitar. He retuned and revoiced his instrument and in 1972 gave it a new name: samvadini, the one that creates harmony.
Why it mattered. It was a bold claim that the harmonium could be a classical solo voice.
Bajaj had built Vespa scooters under licence. In 1972 it launched its own version, the Chetak. Demand was so high that at one point the waiting list was 10 years long.
Why it mattered. For a generation of Indian families, the Chetak was the first vehicle they owned.
James Ambrose and Godfrey HounsfieldBritish Institute of Radiology congress, London
Ambrose and Hounsfield gave the opening paper at the British Institute of Radiology's annual congress, showing brain scans made without contrast agents. The Times reported it the next day, and hospitals around the world began to ask for scanners.
Why it mattered. The announcement set off a race among manufacturers to build CT scanners.
Casoli, a vet by training, made his first kitchen hood and founded Elica in 1970. In 1972 the company showed a hood in Paris and signed its first deal with Philips. Elica later became one of the world's biggest hood makers.
Why it mattered. Italian hood makers turned the kitchen chimney into a common home appliance.
Honda announced its CVCC engine, which lit a rich mixture in a small side chamber so the flame spread through a leaner mixture in the main cylinder. It burned fuel more completely. It met strict new US clean-air limits without a catalytic converter.
Why it mattered. Small, thrifty Japanese cars won millions of new buyers just as fuel suddenly became expensive.
India passed a law creating the Central Council of Homoeopathy to set standards for homeopathic education and keep a central register of practitioners.
Why it mattered. Homeopathy became a regulated profession in India, with the BHMS degree.
The British government asked mathematician James Lighthill to judge AI research. His report said AI had not lived up to its grand promises, and UK funding was cut sharply.
Why it mattered. Together with the doubts after Perceptrons, it marks what people now call the first AI winter.
Sharp's EL-805 was the first product on the market to use a liquid crystal display. Earlier calculators used glowing LEDs or tubes; the LCD cut power to about a hundredth, so the EL-805 ran about 100 hours on one AA battery.
Why it mattered. LCDs made calculators small, cheap and able to run for years on tiny cells.
Standing on Sixth Avenue, Motorola engineer Martin Cooper called Joel Engel, his rival at Bell Labs, on a prototype DynaTAC. It weighed about 1.1 kg and its battery gave some 30 minutes of talk after 10 hours of charging.
Why it mattered. It proved a phone could belong to a person, not a car or a building.
Johansson fixed small lights to an actor's main joints and filmed them moving in the dark. When the dots were still, viewers saw a random pattern. The moment they moved, people instantly saw someone walking, running or dancing.
Why it mattered. It proved that a few moving points hold most of what we read in body movement, which is why a few dozen markers can capture a performance.
For The Exorcist, Dick Smith created shocking make-up and body effects for Linda Blair's character. He made masks in several separate pieces instead of one, so actors' faces could move naturally. A young Rick Baker assisted him on the film.
Why it mattered. The way prosthetics are stuck onto faces today comes largely from Smith's methods.
Ismat Chughtai, Kaifi Azmi and Shama ZaidiAgra and Bombay, India
Garm Hava, about a Muslim family in Agra after Partition, grew from an unpublished story by the writer Ismat Chughtai. The poet Kaifi Azmi and Shama Zaidi wrote the screenplay together. Zaidi and Azmi shared the Filmfare award for Best Screenplay.
Why it mattered. It is a reminder that a screenplay often begins as someone else's story, carefully rebuilt for the screen.
Salim–Javed (Salim Khan and Javed Akhtar)Bombay (now Mumbai), India
When the posters for Zanjeer went up without the writers' names, Salim Khan and Javed Akhtar say they paid a painter to add them by hand. The duo went on to write Deewaar and Sholay (both 1975). They are widely credited as among the first Indian screenwriters to become stars.
Why it mattered. They made audiences and producers see that a film starts with its writers.
Looking at mouse spleens under the microscope, Steinman spotted cells with long branching arms and named them dendritic cells. He showed they are the scouts that wake up T cells. He won the 2011 Nobel Prize, awarded days after his death.
Why it mattered. It explained how the adaptive immune system is switched on.
Stimulating a pathway into a rabbit’s hippocampus with rapid bursts made its synapses respond more strongly for hours or longer. This long-term potentiation (LTP) is a leading cellular model of learning and memory.
Why it mattered. It found in real tissue the kind of change Hebb had predicted.
Kersi Lord, with composer R.D. BurmanBombay (today Mumbai), India
Kersi Lord, a leading Bombay session musician, heard Switched-On Bach and fell for the Moog sound. In 1973 he got a Minimoog, reported to be the first in India, and used it through the 1970s on songs for composer R.D. Burman. Its sweeps and effects became part of the sound of Hindi film music.
Why it mattered. Film songs carried synthesizer sounds to millions of listeners across India.
Paul Lauterbur, and later Peter MansfieldStony Brook, New York; Nottingham
Lauterbur added a gentle slope, or gradient, to the magnetic field, so that each place in the sample answered at a slightly different frequency. From the answers he built the first magnetic resonance image, of two tubes of water. Mansfield in Nottingham made the method fast. They shared the 2003 Nobel Prize.
Why it mattered. It is the basis of every MRI scan today, made in fields of 1.5 to 3 T.
Lauterbur had the idea over dinner in 1971: add a gradient so the field, and the frequency, change with position. Nature first rejected his paper, then published it in 1973 with an image of two small tubes of water. He called the method zeugmatography.
Why it mattered. Gradients turned a signal into a picture, and every MRI since uses them.
Mayo Clinic; Massachusetts General HospitalRochester, Minnesota; Boston
The first EMI scanners in North America were installed at the Mayo Clinic, where the first scan was done on 19 June 1973, and at Massachusetts General Hospital a few weeks later. Each head scan still took minutes per slice.
Why it mattered. Within a few years, dozens of companies were making scanners.
After a wave of hijackings, US airlines had to screen every passenger and their carry-on bags from 5 January 1973. Low-dose X-ray scanners began to look inside bags on moving belts. Airports around the world soon did the same.
Why it mattered. X-rays became part of everyday travel, not only medicine.
Farberware introduced the Convection Turbo Oven, which it calls the first countertop convection oven on the market. A fan and heater moved hot air around the food inside a small cabinet. You no longer needed the big kitchen oven for a small meal.
Why it mattered. It showed that a fan oven could be small enough to sit on a counter.
William Thornton's team, NASASkylab, in Earth orbit
Scales can't work in orbit, so Skylab's crews sat in a chair on springs and let it wobble. A heavier astronaut swings more slowly: the chair's springs had k = 606 N/m and the empty chair's period was 0.848 s. It measured body mass to about 0.1%.
Why it mattered. It weighed people by their inertia alone.
Sontheimer, an engineer who loved French cooking, set up Cuisinart in 1971 and reworked a Robot-Coupe and Magimix machine for American kitchens. He showed it at a trade show in Chicago in January 1973. With help from the chef James Beard it sold well, reaching 290,000 units by 1980.
Why it mattered. In America, ‘Cuisinart’ came to mean any food processor.
In October 1973 Arab oil producers cut supplies to several countries, and the world oil price jumped from about $3 to nearly $12 a barrel. Queues formed at petrol stations. A second shock followed the Iranian Revolution in 1979.
Why it mattered. Governments set fuel-economy rules, and carmakers raced to build smaller, lighter, more efficient cars.
Hub Markwardt, Crompton Greaves and Burton A. BurtonTexas and California, USA, with fans made in India
In 1973 Texas businessman Hub Markwardt began importing ceiling fans made in India by Crompton Greaves. In 1974 Burton A. Burton founded the Casablanca Fan Company in Pasadena. When energy prices soared in the 1970s, fans that used far less power than air conditioning sold fast.
Why it mattered. An energy crisis reminded people that moving air is a cheap way to feel cool.
Edward Shortliffe and colleaguesStanford University, United States
MYCIN held about 600 if-then rules about blood infections. For each patient it chained through them to suggest likely bacteria and a treatment, with a confidence score. In tests its advice compared well with specialists, but it was never used on real patients.
Why it mattered. Every question meant running the same fixed rules again: an early form of inference.
In his PhD thesis, Paul Werbos proposed using this backwards way of computing blame to train networks with many layers. Few people noticed at the time.
Why it mattered. The key idea for training deep networks existed, but it waited twelve years to catch on.
Ed Catmull (attributed); Wolfgang Straßer (independently)University of Utah, USA, and TU Berlin, Germany
The z-buffer stores how far away the nearest surface is at every pixel. When a new surface is drawn, it only wins the pixel if it is closer. The idea is most often credited to Ed Catmull's 1974 thesis, but Wolfgang Straßer described it in his own thesis a few months earlier.
Why it mattered. It is how almost every graphics chip decides what is in front, even today.
Catmull's PhD thesis showed how to draw curved surfaces pixel by pixel, keeping a depth for each pixel so nearer things hide farther ones (the z-buffer, also found by Wolfgang Straßer at the same time), and how to wrap a picture onto a surface: texture mapping.
Why it mattered. Depth buffers and texture maps are still in every 3D program and games console.
This short film about birds and mice working together was shown again and again on Doordarshan. It won the National Film Award for Best Educational Film.
Why it mattered. It made animation part of growing up for a generation of Indian children.
Government of India and Government of KarnatakaBengaluru
The Mental Hospital in Bangalore, with roots in an asylum of 1847, and the All India Institute of Mental Health, opened in 1954, were joined into the National Institute of Mental Health and Neuro Sciences.
Why it mattered. It became India’s leading centre for brain, nerve and mental health care, teaching and research.
Collings repeated the tests on many spots of the tongue and found that all four tastes then known could be sensed everywhere with taste buds. The weakest noticeable strength differed a little from place to place, but no area was blind to any taste.
Why it mattered. It was the scientific end of the tongue map, even if school books kept it for years.
Government of India and the state of KarnatakaBengaluru, India
The Bangalore mental hospital and the All India Institute of Mental Health became the National Institute of Mental Health and Neurosciences, an autonomous institute. It became a deemed university in 1994 and an Institute of National Importance in 2012.
Why it mattered. It became a major centre for brain research, treatment and training in India.
In 1972 the engineer Aoyagi was annoyed by a ‘noise’ in his light signals that went up and down with each heartbeat. He realised that the pulsing red and infrared light could reveal how much oxygen the blood carried. He presented the idea in 1974, and in 1975 Nihon Kohden sold the first ear oximeter.
Why it mattered. Every clip-on finger oximeter, used by millions in the COVID-19 pandemic, works on his idea.
Inspired by Wendy Carlos, Tomita bought a large Moog modular synthesizer and set up a studio at home. He turned piano pieces by Claude Debussy into shimmering, orchestra-like electronic sounds. Snowflakes Are Dancing became a worldwide success and earned four Grammy nominations.
Why it mattered. It showed how carefully programmed synths could paint delicate colours, and it taught players worldwide new programming tricks.
Husbands set up Solar Dynamics, the first solar water heater company in Barbados, just as world oil prices soared. With government support, including tax breaks, solar water heaters spread across the island.
Why it mattered. Barbados became one of the world leaders in solar water heaters per person.
At the University of Nottingham, Mansfield's group described NMR 'diffraction', the forerunner of k-space, in 1973, and a way to excite just one slice with a gradient in 1974.
Why it mattered. Slice selection lets a scanner image one thin section of the body at a time.
Ledley's ACTA scanner could scan the whole body, not just the head, and no longer needed the water bag the EMI scanner used around the head. He was granted a patent for it in November 1975.
Why it mattered. CT moved from the brain to the chest, belly and bones.
Larry Shepp and Benjamin LoganBell Labs, New Jersey
To compare ways of rebuilding images, Shepp and Logan invented a simple head made of ellipses, with a skull, ventricles and small tumours. The Shepp–Logan phantom is still the standard test image for CT maths.
Why it mattered. It gave everyone the same test, so methods could be compared fairly.
GM's Air Cushion Restraint System went into about 11,000 cars from the 1974 model year, starting with the Oldsmobile Toronado. Airbags later became standard worldwide. India made a driver airbag compulsory in 2019 and dual front airbags in all new cars from 2022.
Why it mattered. A cushion of gas makes the head's stop last longer and spreads the force.
Mario Molina and F. Sherwood RowlandUniversity of California, Irvine, USA
Molina, a young Mexican chemist, and Rowland worked out that CFCs from fridges and spray cans drift up to the stratosphere, where sunlight breaks them apart. The chlorine they release destroys ozone, the gas that shields life from ultraviolet light. They shared the 1995 Nobel Prize in Chemistry with Paul Crutzen.
Why it mattered. It revealed that the gas inside a kitchen fridge could harm the whole planet.
Whittingham, an English chemist working for the oil company Exxon, made a battery with a titanium disulfide electrode that lithium ions could slip in and out of. It worked, but its lithium metal side could catch fire, and Exxon gave it up.
Why it mattered. It proved lithium could store a lot of energy in a small, light battery.
Mario Molina and F. Sherwood RowlandUniversity of California, Irvine, USA
Molina, a young Mexican chemist, and Rowland worked out that CFCs drift up to the stratosphere, where sunlight breaks them apart. The chlorine they release destroys ozone, the gas that shields life from ultraviolet light. They shared the 1995 Nobel Prize in Chemistry with Paul Crutzen.
Why it mattered. It revealed that the gases in fridges and air conditioners could harm the whole planet.
Sholay was shot on 35 mm film but blown up for a wide 70 mm release, with the first stereophonic soundtrack in an Indian film. It ran at Bombay's Minerva theatre for more than five years. The wide 70 mm prints needed special projectors and very bright lamps.
Why it mattered. It showed Indian audiences what a wide screen and big sound could do, decades before multiplexes.
Lucas set up his own effects team to make the space battles for Star Wars. He called it Industrial Light & Magic, or ILM. It began in Van Nuys and moved north to San Rafael in 1978.
Why it mattered. ILM went on to lead many of the big firsts in digital effects for the next 45 years.
Phong, born in Hanoi, blended the direction each surface faces across every pixel, not just the brightness. He added a simple recipe for the bright spot you see on a shiny ball. His thesis came in 1973 and his famous paper in 1975, the year he died, aged 32.
Why it mattered. The Phong highlight is one of the first material models every graphics student learns.
Newell needed a test object and modelled a Melitta teapot, typing its curved surfaces into the computer. Researchers everywhere copied the data to try out new shading ideas. The real teapot is now at the Computer History Museum in California.
Why it mattered. A shared test object let people compare their rendering methods fairly.
Phong published a way to shade a surface smoothly across its polygons and add a bright highlight whose size depends on how glossy the surface is. Hollow polygon models suddenly looked like plastic and metal.
Why it mattered. It was the start of shading: telling the computer what a surface is made of.
Newell needed a test object, so his wife Sandra suggested their tea set. He sketched a Melitta teapot on graph paper and described it with curved Bézier patches. It was shared freely and became the most rendered object in computer graphics.
Why it mattered. It gave researchers a common model to compare their programs on; the real teapot is now at the Computer History Museum.
Sholay was released in 70 mm with stereophonic sound, shot on 35 mm and blown up for the big prints. It is widely called India's first 70 mm stereo film, though the 1967 film Around the World was released that way earlier.
Why it mattered. It showed Indian audiences what big, spread-out cinema sound could do.
Bob Mattey, for Steven SpielbergMartha's Vineyard, Massachusetts
Mattey's team built three full-size mechanical sharks powered by air pressure, nicknamed Bruce after Spielberg's lawyer. In salt water the foam skin soaked up water, hoses corroded and frames cracked. The shoot grew from 55 planned days to 159.
Why it mattered. Because the shark rarely worked, Spielberg hid it, and the suspense made Jaws scarier.
Ramesh Sippy (director)Near Panvel, on the Bombay–Poona railway
The famous train robbery in Sholay was filmed on a real railway line near Panvel, with riders chasing a moving train. According to accounts of the production, the sequence took more than seven weeks to film.
Why it mattered. It showed Indian audiences that home-grown action could match any Western on screen.
Barry Lyndon is set in the 1700s, and Kubrick wanted its night scenes lit only by candles. He got three Zeiss 50 mm lenses with an aperture of f/0.7, made for NASA's Apollo programme, and the film was push-processed one stop. Alcott won the Oscar for cinematography.
Why it mattered. It showed that a fast enough lens can let the scene's own light do all the work.
Lucas asked McQuarrie to paint several scenes from his Star Wars script. Lucas took the paintings to 20th Century Fox, and they helped convince the studio to fund the film. McQuarrie also designed many of its characters and sets.
Why it mattered. It made the concept painting famous as a tool for selling an idea, not just planning it.
Georges Köhler and César MilsteinCambridge, England
Köhler and Milstein fused an antibody-making B cell with a cancer cell that never stops dividing. The hybrid made endless copies of one single antibody. They chose not to patent it, so labs everywhere could use it.
Why it mattered. Monoclonal antibodies are now used in pregnancy tests, COVID tests and many cancer and arthritis medicines.
India’s National Smallpox Eradication Programme with WHOAssam
After a massive search-and-contain campaign, with health workers visiting every village to find cases and vaccinate everyone around them, India recorded its last case of smallpox in 1975. India was declared smallpox-free in 1977.
Why it mattered. India, once home to most of the world’s smallpox cases, had beaten the disease.
In 1972 the engineer Aoyagi was annoyed by a 'noise' in his light signals that rose and fell with each heartbeat. He realised that pulsing red and infrared light could show how much oxygen the blood was carrying. He presented the idea in 1974, and in 1975 Nihon Kohden sold the first ear oximeter.
Why it mattered. Every clip-on finger oximeter, used by millions in the COVID-19 pandemic, works on his idea.
Indian Society of Blood Transfusion and ImmunohaematologyIndia
India first marked National Voluntary Blood Donation Day on 1 October 1975, the birthday of the society's founder, Dr J. G. Jolly. It is still held every year to encourage unpaid donors.
Why it mattered. Voluntary, unpaid donors give the safest blood.
James Rheinwald and Howard GreenCambridge, Massachusetts, USA
James Rheinwald and Howard Green found how to grow human skin cells, called keratinocytes, in the lab on a layer of mouse “feeder” cells. A few cells from a small piece of skin could multiply into sheets of new epidermis. They published it in the journal Cell in 1975.
Why it mattered. For the first time, new skin could be made in large amounts from a tiny sample.
Dermatologist Thomas Fitzpatrick made a scale of skin types based on how easily skin burns or tans in the sun. It was built to choose safe doses of UV light for a psoriasis treatment called PUVA, not to describe skin colour. The first version had four types for white skin, and types V and VI for brown and black skin were added later.
Why it mattered. It became the standard way to predict how skin reacts to sunlight, though it was never meant to cover every skin tone.
B. N. Tandon and colleaguesAIIMS New Delhi and PGI Chandigarh
Diagnostic endoscopy was started in the early and mid-1970s at central institutes, the Postgraduate Institute in Chandigarh and the All India Institute of Medical Sciences in New Delhi, with B. N. Tandon at AIIMS among the pioneers. Specialist gastroenterology departments grew in Mumbai, Kolkata and elsewhere.
Why it mattered. It brought the new flexible scopes to one of the world’s largest populations.
Ghulam Farid Sabri and Maqbool Ahmed Sabri from Karachi sang and played harmonium in their qawwali group. In 1975 they performed at Carnegie Hall in New York, said to be the first qawwali performance in the West. Their harmonium drones and rolling rhythms amazed new audiences.
Why it mattered. It carried the harmonium's sound far beyond South Asia.
Samta Prasad of the Benares gharana played tabla for Hindi films such as Meri Surat Teri Aankhen (1963) and Sholay (1975). The composer S. D. Burman is said to have held up a recording until he could travel from Benares. Film composers R. D. Burman and Bappi Lahiri were among his students.
Why it mattered. Through film songs, the tabla became a sound nearly everyone in India knows.
John McLaughlin, L. Shankar, Zakir Hussain and Vikku VinayakramUSA and India
English guitarist John McLaughlin formed the band Shakti with Indian musicians, including a young Zakir Hussain on tabla. Their first album was recorded live on 5 July 1975 at Southampton College in New York. They mixed Indian classical music with jazz at breathtaking speed.
Why it mattered. Shakti showed the tabla could lead in a band, not just keep time.
Anil Kumar, Dieter Welti and Richard ErnstZurich, Switzerland
At ETH Zurich, Ernst's group showed how to build MR images with phase and frequency encoding and a Fourier transform. Ernst won the 1991 Nobel Prize in Chemistry for his work on NMR methods.
Why it mattered. Nearly every clinical scanner still fills k-space and uses a Fourier transform this way.
After tests at Frankfurt's university hospital from 1974, Siemens began series production of its SIRETOM head scanner in November 1975. In 1977 its SOMATOM body scanner took about four seconds per slice.
Why it mattered. Scan times fell from minutes to seconds in just a few years.
At the National Physical Laboratory, Kibble designed a balance that compares mechanical power, a mass moving in gravity, with electrical power in a coil. It was called the watt balance.
Why it mattered. Power became precise enough to define the kilogram itself.
ISRO and NASA, championed by Vikram SarabhaiSix states of India
For one year, NASA’s ATS-6 satellite beamed programmes on farming, health and schooling to more than 2,400 villages. Each village got a TV set and a dish antenna 3 metres wide. At first, 200 to 600 people gathered round a single set.
Why it mattered. It proved that satellites could bring television to places no tower could reach.
Carmakers, under the US Clean Air ActUnited States
From the 1975 models, most new petrol cars in the US got catalytic converters to meet new limits on carbon monoxide and unburnt fuel. They needed unleaded petrol, because lead ruins the catalyst. Three-way converters that also clean NOx followed a few years later.
Why it mattered. They cut the poisons from incomplete burning, though every gram of fuel carbon still leaves as CO₂.
Amana added an automatic defrost setting in 1974. In 1975 its RR-6 model became the first microwave with a microprocessor and a digital touch panel instead of a turning dial.
Why it mattered. The beeping number pad on today's microwaves began here.
To meet clean-air rules, most new petrol cars in the United States from the 1975 model year had a catalytic converter in the exhaust. Precious metals inside turn poisonous gases into less harmful ones. Lead in petrol ruins the catalyst, so unleaded petrol spread alongside it.
Why it mattered. It sharply cut the smog made by car exhausts, and cars around the world now carry one.
Sasson's prototype weighed about 3.6 kg, captured a 100 × 100 pixel (0.01 megapixel) black-and-white image, and took 23 seconds to record it onto a cassette tape.
Why it mattered. Kodak had invented the technology that would later end its film business.
Post Office Code Standardisation Advisory Group (POCSAG)London
The British Post Office, then running the UK's phones, gathered engineers from several companies to design a common digital code for paging, so any maker's pager could work on any network.
Why it mattered. A shared standard let paging spread across countries.
IBM's 3800 printed 215 pages a minute at 240 dots per inch on continuous paper. It was a room-sized machine for big computer centres. Xerox followed with its 9700 in 1977.
Why it mattered. Businesses could now print bills and statements by the million.
Brown built a vest, a spring-loaded arm and a balanced post that let an operator walk or run while the camera glided smoothly. It was first used on films released in 1976, including Bound for Glory, Marathon Man and Rocky, whose run up the museum steps became famous. Brown won an Oscar for it in 1978.
Why it mattered. Smooth moving shots no longer needed tracks laid on the ground.
By sealing a tiny glass pipette onto a cell, they recorded the current through one ion channel as it snapped open and shut. They won the 1991 Nobel Prize.
Why it mattered. It proved the gates Hodgkin and Huxley imagined are real molecules.
Popovich and Moncrief worked out continuous ambulatory peritoneal dialysis: fluid is left in the belly and swapped a few times a day, so wastes pass across the belly's own lining. People could do it at home.
Why it mattered. It gave people with kidney failure an option without a machine.
James Black and colleagues at Smith, Kline & FrenchWelwyn Garden City
Cimetidine (Tagamet) blocks the histamine signal that tells parietal cells to make acid. Launched in the UK in 1976, it let many ulcers heal without surgery. James Black shared the 1988 Nobel Prize.
Why it mattered. It began the era of acid-reducing medicines.
After retiring as a government eye surgeon, Dr Venkataswamy opened an 11-bed eye clinic. Aravind Eye Hospitals grew into one of the world's largest eye care providers, doing hundreds of thousands of surgeries a year with most poor patients paying little or nothing.
Why it mattered. Its high-volume, low-cost model has been copied around the world.
India launched the National Programme for Control of Blindness, with cataract surgery at its heart. It is now the National Programme for Control of Blindness and Visual Impairment and supports millions of cataract operations every year, many of them free.
Why it mattered. It turned cataract surgery into a public health campaign across a vast country.
Werner Stengel; Revolution coasterSix Flags Magic Mountain, California, USA
The Revolution was the first modern steel coaster with a vertical loop. Its designer Werner Stengel shaped it as a clothoid, tight at the top and wide at the bottom, so riders never feel the 6 g of a round loop.
Why it mattered. Almost every looping coaster since uses the same curve.
Between 1947 and 1974, the average American fridge went from using under 400 kWh of electricity a year to over 1,800 kWh. After the 1970s energy crisis, California set the first ever efficiency standards for fridges in 1976. Other states followed, and a national law was signed in 1987.
Why it mattered. Rules that capped energy use pushed makers to add better foam insulation and better compressors.
Servis released the Selectronic 301, described as the world's first washing machine run by a microcontroller, a tiny computer chip. Before this, a clockwork-like timer with turning cams switched each part of the cycle on and off.
Why it mattered. Chips let machines sense the load, choose water levels and run gentler or faster programs.
The Apple II came ready to use, in a plastic case with a keyboard, and could show colour on a TV. It was one of three popular home computers of 1977, along with the Commodore PET and TRS-80.
Why it mattered. Computers moved from company basements into homes and schools.
At Canon, a hot soldering iron touched a syringe needle full of ink, and drops shot out of the tip. Canon's researchers turned this into the Bubble Jet idea and filed a basic patent in 1977. At about the same time, John Vaught's team at HP found that thin-film resistors could fire ink drops too.
Why it mattered. Boiling ink with a tiny heater became the thermal inkjet, the most common home printer in the world.
John Dykstra and ILM, for Star WarsVan Nuys, California, USA
The Dykstraflex was a camera rig run by a computer. It could pan, tilt, roll and glide down a track, then repeat the exact same move as many times as needed. That let the team film each spaceship model separately and stack the shots perfectly.
Why it mattered. Repeatable, recorded camera moves are the ancestor of today's camera tracking, where the computer matches the real camera.
Dolby Stereo squeezed four channels (left, centre, right and surround) into the space of one old optical track. First used in 1976, it spread fast after Star Wars showed off its sound in 1977, and many cinemas installed stereo for the first time.
Why it mattered. Stereo and surround became normal in ordinary cinemas, not just a few showcase halls.
For Star Wars, Ben Burtt recorded real things and layered them. The lightsaber hum came from an idling film projector and the buzz of a broken TV set. He won a special Academy Award for the film's alien, creature and robot voices.
Why it mattered. It showed that recorded, layered and pitched sounds could make impossible things feel real.
George Lucas; John Dykstra; Industrial Light & MagicVan Nuys, California
For Star Wars, Lucas set up Industrial Light & Magic in a warehouse in 1975. Its team filmed small model spaceships with the Dykstraflex, a computer-controlled camera that could repeat the same move exactly. The film won six Oscars in 1978, including one for visual effects.
Why it mattered. Motion control let many models be filmed separately and combined into one huge battle.
While the effects shots for Star Wars were still being made, Lucas cut clips of World War II air battles from old films into the edit. They showed the effects team the speed and camera moves he wanted. Artists later matched some shots almost frame by frame.
Why it mattered. It was a moving sketch of a scene, the idea behind every animatic.
George Lucas; Industrial Light & MagicVan Nuys, California
Lucas set up his own effects company, ILM, in 1975 because no studio could make his space battles. Its team built a computer-controlled camera that could repeat the same move exactly, so separately filmed models could be layered together.
Why it mattered. It launched the modern visual-effects industry and the age of the effects blockbuster.
Eugene Goldwasser, Takaji Miyake and Charles KungUniversity of Chicago
After years of work, Goldwasser's team purified human erythropoietin from a large amount of urine. The gene was later cloned and, from 1989, man-made EPO was used for anaemia in people with kidney failure.
Why it mattered. It proved the kidney makes a hormone for red blood cells, and turned it into a medicine.
Andreas GrüntzigUniversity Hospital Zurich, Switzerland
Grüntzig threaded a thin tube with a tiny balloon into a narrowed artery on the heart of Adolf Bachmann, a 38-year-old with chest pain. He blew up the balloon to squash the blockage open. No chest was cut open.
Why it mattered. It started interventional cardiology, and today stents placed this way treat millions of people.
US Naval Research Laboratory, NTS-2Launched from Vandenberg, USA
NTS-2, the first satellite for the new GPS system, carried the first caesium atomic clock into orbit. Before its correction was switched on, it ran fast by 442.5 parts in 10¹², close to the 446.5 relativity predicted. GPS clocks have been tuned to cancel this ever since: about 38 microseconds a day.
Why it mattered. Without relativity, GPS positions would drift by kilometres every day.
Peter Mansfield and Andrew MaudsleyNottingham, England
Mansfield and Maudsley published cross-sections of a living human finger, made in 1976. The same year Mansfield described echo-planar imaging, a way to make a whole picture from a single pulse in a fraction of a second.
Why it mattered. Echo-planar imaging later made fMRI and diffusion scans possible.
Raymond Damadian and his teamBrooklyn, New York, USA
Damadian's team built a superconducting scanner they named Indomitable. Graduate student Larry Minkoff sat inside for nearly five hours while it gathered 106 points, one at a time, to make a rough cross-section of his chest. The machine is now in the Smithsonian's collection.
Why it mattered. It was the first MR scan of a whole human body.
In 1970 the Sumeet trademark was registered with Madhuri Mathur as its owner, and in the 1970s Sumeet designed one jar that could dry grind, wet grind and liquidise. A price cut from Rs 960 to Rs 740 helped monthly sales jump from about 2,000 to about 17,000 in 1976 to 1977. By 1980 it made 50,000 mixies a month and had opened a motor factory in Madras.
Why it mattered. The mixie stopped being a rare luxury and became something middle-class families saved up for.
Twelve years after Indane began, India had only about 3.2 million LPG connections, enough for about 2.5% of households. Almost everyone else cooked on chulhas burning wood, crop waste, dung or coal, often in small rooms with no chimney.
Why it mattered. It shows how far India had to go, and how much smoke women and children were breathing.
Joe Breeze, with Gary Fisher, Charles Kelly and othersMarin County, California, USA
Riders racing old bikes down Mount Tamalpais wanted something tougher. Joe Breeze built the Breezer, one of the first purpose-built mountain bikes, with wide tyres, strong brakes and many gears.
Why it mattered. A new kind of cycling, and bikes that go almost anywhere.
A joint research council for Indian medicine and homoeopathy was split into separate councils, one of them the Central Council for Research in Yoga & Naturopathy (CCRYN).
Why it mattered. Yoga and naturopathy got their own national research body.
The Central Council for Research in Indian Medicine and Homoeopathy (1969) was split into separate councils. Siddha research came under the Central Council for Research in Ayurveda and Siddha (CCRAS).
Why it mattered. For 32 years Siddha research was run jointly with Ayurveda.
The Central Council for Research in Unani Medicine (CCRUM) was set up to study Unani medicines and treatments, with institutes around India, including the Central Research Institute of Unani Medicine in Hyderabad.
Why it mattered. Unani research got its own national body.
The Central Council for Research in Homoeopathy was set up to run research on homeopathy, including drug provings, drug standards and clinical studies. It now has institutes across India.
Why it mattered. Few countries have a government research council devoted to homeopathy.
The Central Council for Research in Indian Medicine and Homoeopathy (1969) split into separate councils. The Ayurveda one became today’s CCRAS, which runs clinical studies, drug standards and plant surveys.
Why it mattered. It gave Ayurveda a national research body.
Sharp's EL-8026 of 1976 used a solar cell to recharge its batteries. The Teal Photon of 1978 was among the first calculators to run on light alone, but needed bright light. Scientific solar calculators followed in 1982.
Why it mattered. CMOS chips and LCDs had cut power so far that a small solar cell was enough.
Rank Cintel's TOPSY system let an operator store colour settings for each scene. The telecine could then replay them as the film ran. Before this, operators had to twist knobs live as each shot went by.
Why it mattered. Remembering a correction for every shot is what makes shot matching possible.
Perisic's Zoptic system linked zoom lenses on the camera and the front projector. Zooming both together made the actor seem to fly towards or away from the camera while the background stayed the same size.
Why it mattered. Camera and background were being controlled together, an early step towards tracking.
Catmull and Clark published a rule for splitting every face of any mesh into smaller ones and smoothing the corners, over and over, until a blocky cage becomes a smooth surface. It is the subdivision in chapter 1.
Why it mattered. Almost every film character since the late 1990s is built as a subdivision surface.
Much of Days of Heaven was filmed in the short glow after sunset, when the sky is bright but the sun has gone. Almendros called it the magic hour, and it gave only about 25 minutes of shooting a day. He used very little studio lighting and won the Oscar for cinematography.
Why it mattered. It made golden hour and magic hour part of every cinematographer's vocabulary.
Patrick Steptoe and Robert Edwards (with Jean Purdy)Oldham, England
After years of work, a gynaecologist and a scientist joined an egg and sperm in a lab dish and placed the early embryo in the mother's uterus. Louise Brown was born healthy. Robert Edwards received the Nobel Prize in 2010.
Why it mattered. It gave hope to millions of people with infertility.
Dr Subhas Mukhopadhyay (with Sunit Mukherji and Saroj Kanti Bhattacharya)Kolkata, India
Just 70 days after Louise Brown, a baby girl named Durga, later known as Kanupriya Agarwal, was born in Kolkata. Dr Subhas Mukhopadhyay and his colleagues had used their own methods and simple equipment. A government committee refused to believe him, and he died in 1981. Years later, experts reviewed his notes and recognised his work.
Why it mattered. India was only the second country with an IVF baby, and Mukhopadhyay is now honoured as a pioneer.
Genentech scientists; Eli LillySouth San Francisco and Indianapolis, USA
For 60 years insulin came from pig and cow pancreases. In 1978 scientists put the human insulin gene into bacteria, which then made human insulin. In 1982 it became the first medicine made this way to be approved.
Why it mattered. It gave the world a steady supply of human insulin and launched the biotech industry.
A Lancet editorial called the discovery that glucose speeds the absorption of salt and water potentially the most important medical advance of the century. WHO and UNICEF were spreading ORS packets worldwide.
Why it mattered. A cheap packet became one of the great life-savers of the 20th century.
Reinhold Messner and Peter HabelerMount Everest, Nepal
At the top of Everest the air holds only about a third as much oxygen as at sea level. Many experts thought a person could not survive there without bottled oxygen. Messner and Habeler climbed to the summit breathing only the thin air.
Why it mattered. It showed how far a well-acclimatised body can push its breathing and blood.
Manohar H. KeswaniBai Jerbai Wadia Hospital, Mumbai
Burns surgeon Manohar Keswani set up India's first skin bank in Mumbai, to store skin donated after death so it could cover burn wounds. He had already opened the country's first children's burns unit there in 1975. The bank struggled for money and public awareness, but skin banking has since spread to other Indian cities.
Why it mattered. Donated skin can act as a living bandage that helps save people with very large burns.
Genentech and City of Hope scientists; Eli LillySouth San Francisco and Duarte, USA; Indianapolis, USA
In 1978 a team including David Goeddel, Arthur Riggs and Keiichi Itakura got bacteria to make human insulin from synthetic genes. Eli Lilly scaled it up, and in October 1982 the US approved Humulin, the first medicine made by genetic engineering.
Why it mattered. Insulin no longer had to come from the pancreases of cows and pigs, and biotech medicine was born.
The most important medical advance of the century?
The Lancet; World Health OrganizationLondon, England, and Geneva, Switzerland
In 1978 the medical journal The Lancet wrote that the discovery that glucose helps the gut absorb sodium and water was potentially the most important medical advance of the century. The same year, WHO started its programme to control diarrhoeal diseases. It spread oral rehydration salts around the world with UNICEF.
Why it mattered. It turned a lab discovery into a worldwide life-saving campaign.
Kemp placed a tiny microphone in the ear canal and found that the cochlea sends out faint echoes of sounds played into it. These otoacoustic emissions come from the outer hair cells.
Why it mattered. The discovery led to quick, painless hearing screening for newborn babies.
Clark's team implanted a multichannel device in Rod Saunders, who was totally deaf. Its electrodes, spread along the cochlea, used the place map to send different pitches to different nerve fibres. As the Nucleus implant it was approved by the US FDA for adults in 1985.
Why it mattered. Hundreds of thousands of people, including children born deaf, now hear with cochlear implants.
Dave Smith and John Bowen (Sequential Circuits)California, USA
Dave Smith put a microprocessor inside an analog synthesizer. The Prophet-5 could play five notes at once and was the first polyphonic synth to save every knob setting in memory. Before, players had to write settings down and turn all the knobs again by hand.
Why it mattered. Sound memory made synths practical on stage, and it made presets part of music.
Bosch's electronic ABS became an option on the Mercedes-Benz S-Class. Sensors watch each wheel, and valves release the brake pressure many times a second whenever a wheel starts to lock, so the tyres keep rolling with static grip.
Why it mattered. Cars could now brake hard and still steer.
According to the Indian Society of Neuroradiology, India's first CT scanner, an EMI 1010, was set up at AIIMS in 1978, and by the mid-1980s scanners were being installed across the country. Other hospitals also claim early scanners, so exact firsts are debated.
Why it mattered. CT soon replaced older, painful brain tests such as pneumoencephalography in India too.
Maya Appliances started the Preethi brand in Chennai in 1978. It became a favourite mixer grinder of the South, and in 2011 the company said it had nearly 80% of the mixer grinder market in Tamil Nadu and 45% in South India.
Why it mattered. It showed how much Indian cooks trusted a machine made nearby for their own food.
The most important medical advance of the century?
The LancetLondon, England
An editorial in The Lancet, Water with sugar and salt, said the discovery that sodium and glucose are absorbed together in the gut, pulling water with them, was potentially the most important medical advance of this century.
Why it mattered. It is a striking claim for a drink that costs almost nothing, and oral rehydration has since saved many millions of children.
Hitachi, Jun-ichi Nishizawa, Alex Lidow and Tom HermanJapan and California, USA
In 1969 Hitachi showed the first vertical power MOSFET, and in the 1970s Nishizawa's power transistors went into Yamaha amplifiers. In 1977 Lidow and Herman invented the HEXFET at Stanford, and International Rectifier sold it from 1978. These switches can turn on and off many thousands of times a second.
Why it mattered. Fast, cheap MOSFETs are what many home inverters use to chop battery DC into AC.
Doctors used Doppler ultrasound to measure how fast blood squirts through a narrowed heart valve, then worked out the pressure drop with a simplified Bernoulli equation: Δp ≈ 4v². It matched pressures measured with catheters.
Why it mattered. Cardiologists still use this every day to judge valve disease without surgery.
Lucasfilm set up a Computer Division and asked Catmull to lead it. The group worked on digital film editing, compositing and 3D rendering, and hired researchers who would later write RenderMan.
Apocalypse Now was the first film to credit anyone as Sound Designer: Walter Murch, who is widely credited with coining the title. Its 70 mm release used three screen channels, a low-frequency channel and split surrounds, the layout now called 5.1.
Why it mattered. Sound became a creative craft with its own leader, and 5.1 became the standard layout.
H. R. Giger; Carlo Rambaldi; Nick Allder; Brian Johnson; Dennis AylingShepperton Studios, England
Alien's monster was designed by artist H. R. Giger and brought to life with costumes, puppets and mechanical effects. The team won the Oscar for visual effects. Much of the creature stays in shadow, so your imagination fills in the rest.
Why it mattered. It proved a practical creature, shown carefully, can be scarier than one shown in full.
Ridley Scott, who trained in art and design, drew his own storyboards for Alien in ink and pencil. His crew nicknamed them Ridleygrams. The studio was reportedly so impressed by his drawn plan that it gave the film a much bigger budget.
Why it mattered. A good storyboard can sell a film before a single frame is shot.
Syd Field's book Screenplay: The Foundations of Screenwriting said a film has three acts: set-up, confrontation and resolution. Big turning points, called plot points, push the story from one act to the next, roughly 20 to 30 minutes in and 80 to 90 minutes in. The book became a bestseller and a guide for generations of writers.
Why it mattered. It gave writers a simple map for where things should happen on the page.
The pathologist Robin Warren kept seeing small curved bacteria on stomach biopsies, always with inflammation. Textbooks said nothing could live in stomach acid.
Why it mattered. One careful observer refused to ignore what he saw.
Peter Vogel and Kim Ryrie (Fairlight)Sydney, Australia
Two young Australians built a computer music system with a screen and a light pen. When they recorded a real piano note and played it back at different pitches, it sounded far more real than any synth. They called it sampling, and Kate Bush, Peter Gabriel, Stevie Wonder and many others used the Fairlight CMI through the 1980s.
Why it mattered. Sampling turned any recorded sound, even a dog's bark, into an instrument, and it changed pop music.
The Nobel Prize in Physiology or Medicine went to a physicist and an engineer for the development of computer-assisted tomography. Neither was a doctor, and Cormack had no PhD. Oldendorf, who had shared a major prize with Hounsfield in 1975, was left out.
Why it mattered. It recognised that the theory and the machine had been invented separately, on two continents.
Bryan Allen, Paul MacCready's teamFolkestone, England to Cap Gris-Nez, France
Cyclist Bryan Allen pedalled the Gossamer Albatross 35.7 km across the English Channel in 2 hours 49 minutes, producing about 300 W, just enough to keep the ultralight plane in the air.
Why it mattered. It shows how much a fit person can do with a few hundred watts.
David Kirke and Simon Keeling, Oxford University Dangerous Sports ClubClifton Suspension Bridge, Bristol, England
Inspired by the land divers of Vanuatu, who jump from towers with vines tied to their ankles, club members jumped from the bridge on elastic cords. A. J. Hackett opened the first permanent commercial jump at the Kawarau Bridge in New Zealand in 1988.
Why it mattered. A bungee cord is a long, soft spring: it stores the whole fall's energy as ½ k x² and gives it back.
The British firm JCB formed a joint venture with Escorts to make hydraulic backhoe loaders in India. The machines became so common that many Indians call any digger a “JCB”, whatever its maker.
Why it mattered. Hydraulic machines built India's roads and buildings, and gave the language a new word.
World Health Organization and health workers everywhereGeneva, Switzerland
After a global campaign of vaccination and tracing every case, the World Health Assembly declared smallpox eradicated. India’s last case had been in May 1975, after tens of thousands of Indian health workers searched house to house.
Why it mattered. It is the only human disease ever wiped out.
Kunihiko FukushimaNHK Broadcasting Science Research Laboratories, Tokyo, Japan
Inspired by Hubel and Wiesel, Kunihiko Fukushima built a network of layers: simple cells that find small features and complex cells that pool them, so a shape could be recognised even when shifted.
Why it mattered. It is the direct ancestor of the convolutional network, with filters and pooling, the design this box trains.
John McDermott (Carnegie Mellon University) for Digital Equipment CorporationSalem, New Hampshire, United States
XCON (first called R1) used thousands of rules to check and complete orders for VAX computers. By 1986 it had handled 80,000 orders with 95 to 98% accuracy, and was estimated to save DEC about $25 million a year.
Why it mattered. One of the first AI systems answering real questions, every day, for a business.
Kunihiko Fukushima built a layered network for recognising handwritten shapes. Early layers spotted small strokes, and later layers combined them into bigger patterns, an idea inspired by studies of the cat's visual cortex.
Why it mattered. Its design is the ancestor of the convolutional networks that read images today.
Numeric pagers added a small display that showed the caller's phone number. Around 1980 there were said to be about 3.2 million pagers in use worldwide.
Why it mattered. You no longer had to phone the office just to find out who wanted you.
Group 3 made fax digital: 1,728 dots a line, 3.85 or 7.7 lines per mm, Modified Huffman compression and a standard handshake. A page took well under a minute; at 9,600 bit/s, a typical page takes about 10 seconds.
Why it mattered. Nearly every fax machine and fax modem since speaks Group 3. The chapters of this box are its rules.
Whitted let a ray that hits a mirror or glass split into new rays, one reflected and one bent through the glass, and followed each of them in turn. The result was glass balls and mirrors that looked startlingly real. Each picture took the computers of the day a very long time to finish.
Why it mattered. Recursive ray tracing gave reflections, refraction and sharp shadows in one clean method.
Kurosawa trained as a painter before he made films. To win backing for Kagemusha, he painted colourful storyboard pictures of its scenes, and he kept painting them for later films such as Ran (1985) and Dreams (1990). The paintings have since been shown in museums.
Why it mattered. A storyboard can capture colour and mood, not just where the camera goes.
After the last natural case, in Somalia in 1977, the World Health Assembly declared smallpox eradicated. A disease that killed an estimated 300 million people in the 20th century alone was gone.
Why it mattered. It is still the only human disease ever eradicated, proof that vaccines plus herd immunity work.
Premature babies often lack surfactant, the soapy liquid that stops air sacs from collapsing. Fujiwara's team made surfactant from cow lungs and gave it through a tube to ten very sick newborns. Their oxygen levels rose quickly, and the results were published in The Lancet.
Why it mattered. It turned a discovery about the air sacs into a treatment used in newborn units around the world.
Christian Chaussy, Egbert Schmiedt and Dornier engineersMunich
A machine from Dornier, an aircraft company that had studied shock-wave damage, focused shock waves on a kidney stone from outside the body while the patient lay in a water bath. The stone broke into bits small enough to pass.
Why it mattered. Many stones could now be treated without cutting the body open.
Fujiwara’s team in Japan made a surfactant from cow lungs and gave it through a tube to ten very sick premature babies. Their oxygen levels improved quickly, and their X-rays cleared. The results were published in The Lancet.
Why it mattered. It turned Avery’s discovery into a treatment now used in newborn units around the world.
Casio, famous for calculators, launched the Casiotone 201, a keyboard with a built-in speaker and the sounds of 29 instruments. It was sold as a keyboard with full-size keys that anyone could afford. Cheap Casio keyboards spread around the world, including India, where Casio now sells keyboards with Indian tones and rhythms.
Why it mattered. Low-cost keyboards put electronic sound into ordinary homes, schools and bands.
Roland's TR-808 Rhythm Composer made drum sounds with analog circuits instead of recordings, so they did not sound like real drums. It flopped at first, and only about 12,000 were made. Cheap second-hand 808s then shaped hip hop, electro and dance music, and its booming bass drum is still everywhere.
Why it mattered. It proved a machine could invent new sounds people love, not just copy old ones.
After the oil crises of the 1970s, Israel required solar water heaters on all new homes, except tall towers without enough roof space. Solar heating became a normal part of Israeli homes.
Why it mattered. It became one of the best-known examples of a country making solar hot water the normal choice.
The University of Aberdeen's home-built Mark-One scanner, with a 0.04 T magnet, scanned a man with cancer and revealed a tumour in his spine that other tests had not found. It went on to scan thousands of patients.
Why it mattered. It showed MRI could change what doctors did for a patient.
John Goodenough and Koichi MizushimaUniversity of Oxford, England
Goodenough and his team, including the Japanese scientist Koichi Mizushima, used lithium cobalt oxide for the positive electrode. It gave a much higher voltage than Whittingham's battery and was stable in air.
Why it mattered. A stronger cathode made a powerful lithium battery possible.
Toshiba released what it calls the world's first inverter-based home air conditioner; other sources say inverter models reached shops in 1980–1981. Electronics change the compressor's speed smoothly instead of just switching it on and off.
Why it mattered. Running slowly and steadily saves a lot of energy, and most new air conditioners now work this way.
In very thin layers of electrons, cold and in a strong magnetic field, von Klitzing found the Hall resistance locks onto exact steps of h/e², about 25,812.807 Ω, whatever the sample. He won the 1985 Nobel Prize, and from 1990 labs used it to calibrate resistance.
Why it mattered. The best standard of resistance became a law of nature, not a column of mercury.
Hubel and Wiesel shared the Nobel Prize in Physiology or Medicine for their discoveries about how the visual system processes information, with Roger Sperry, who was honoured for separate work on the brain's two halves.
Why it mattered. Their map of the visual cortex is still the textbook starting point, and EyeClear and BrainClear show the living version.
IBM launched its Personal Computer, built mostly from parts other companies made, including an Intel processor and Microsoft's DOS. Other firms soon built 'clones' that ran the same software.
Why it mattered. Its open design became the standard for most desktop computers for decades.
The international radio committee accepted the Post Office code as Radiopaging Code No. 1, later ITU-R Recommendation M.584. It sends 32-bit codewords with 10 check bits, in batches of 8 frames, at 512 bits a second, later 1,200 and 2,400.
Why it mattered. The same code, sync word and error correction are still used today.
Introvision was a front projection system that could combine actors with both background plates and models. It was first used in Outland, putting Sean Connery into a mining colony on a moon of Jupiter.
Why it mattered. Front projection stayed in use until computer effects replaced it in the 1990s.
Frank Thomas and Ollie JohnstonNew York (Abbeville Press)
Two of Disney’s senior animators wrote down the 12 principles of animation: squash and stretch, anticipation, staging, straight ahead and pose to pose, follow-through, slow in and out, arcs, secondary action, timing, exaggeration, solid drawing and appeal.
Why it mattered. It became the “bible” of animation, taught to hand-drawn and 3D animators alike.
Merck (USA) and the Institut Pasteur (France)USA and France
The first hepatitis B vaccines were made from purified virus proteins taken from the blood of infected people. They were licensed in 1981 in the United States and France. Because long hepatitis B infection can cause liver cancer, it was the first vaccine able to prevent a human cancer.
Why it mattered. It showed a vaccine could protect the liver for life.
Ciani made sounds with a Buchla synthesizer for TV adverts and pinball games, including a famous bottle pop-and-pour sound for Coca-Cola. In 1981 she scored the Hollywood film The Incredible Shrinking Woman. She is credited as the first woman to score a major Hollywood film on her own.
Why it mattered. She showed that synthesizer sound design could be a career, and opened doors for women in film music.
Roland (designer Tadao Kikumoto); later PhutureJapan and Chicago, USA
Roland made the TB-303 to play bass lines, but it sounded nothing like a bass guitar and sold poorly, so it was dropped in 1984. In 1987 the Chicago group Phuture twisted its filter knobs while it played. The squelchy sound of their track Acid Tracks helped start acid house.
Why it mattered. Sweeping a filter's cutoff and resonance while a note plays became one of dance music's signature sounds.
APPLE, the Ariane Passenger Payload Experiment, was India's first experimental communication satellite in geostationary orbit, parked at 102° E. It relayed TV and radio for two years and led to the INSAT and GSAT satellites that serve India today.
Why it mattered. It showed India could place and run a satellite that hangs over one spot of the Earth.
FONAR offered the first commercial whole-body scanner around 1980–81. At Hammersmith Hospital in London, a team from EMI made the first series of brain images in 1981, and GE showed 1.5 T images in 1983. The US FDA approved the first MRI systems for sale in 1984.
Why it mattered. MRI moved from physics labs into hospitals.
John Cadotte made a polyamide skin only a fraction of a micrometre thick by letting two chemicals react right at the boundary between water and oil, on top of a porous support. His patent was granted in 1981, and FilmTec made it into the FT-30 membrane.
Why it mattered. Nearly every RO purifier and desalination plant today uses this kind of thin-film composite membrane.
John Cadotte made a new kind of membrane by letting two chemicals meet where water and oil touch. They react into a polyamide layer far thinner than a hair, right on top of a porous support. His patent reported over 99.3% salt rejection with high flow.
Why it mattered. Almost every RO membrane made today, at home or in giant plants, is a thin-film composite like his.
David Marr's book, published after his early death in 1980, described vision as a series of steps: from edges to a sketch of surfaces to 3D objects. It shaped how researchers thought about vision for years.
Why it mattered. It gave computer vision a clear plan of stages, many of which learned networks later handled on their own.
Physicist John Hopfield described a network that stores patterns like memories. Give it a damaged or partial pattern and it settles, step by step, into the closest stored one, like a ball rolling into a valley.
Why it mattered. It brought physicists into the field and helped wake neural networks from their winter.
MAGI, Information International Inc., Robert Abel and Associates, Digital EffectsUSA
Disney's Tron used about fifteen to twenty minutes of computer animation made by four graphics companies. Memory was so small that artists faded distant objects into black to save detail. Some complex frames reportedly took up to six hours each to render.
Why it mattered. It showed Hollywood that computers could make whole scenes, not just titles.
Steven Lisberger; MAGI, Triple-I, Robert Abel and Associates, Digital EffectsBurbank, California
Disney's Tron had about 15 to 20 minutes of computer animation: light cycles, tanks and glowing landscapes, made by four companies. Its director later said it was not nominated for visual effects because voters felt using computers was cheating.
Why it mattered. It showed audiences a whole world built from 3D models.
For the Genesis sequence in Star Trek II, a wall of fire spreads across a dead planet. Reeves drew it with hundreds of thousands of tiny points, each born, moved by simple rules and faded. He published the idea as the particle system in 1983.
Why it mattered. Particles are still how films make fire, sparks, smoke, rain and magic.
At the 54th Academy Awards, Rick Baker won the first competitive Oscar for Best Makeup for An American Werewolf in London (1981). The man-to-wolf change happens in bright light, using stretching rubber skin and mechanical parts. Baker went on to win seven make-up Oscars, a record.
Why it mattered. Make-up effects finally had an award of their own every year.
Rob Bottin; Stan WinstonUniversal Studios, California
Rob Bottin was just 21 when he led the creature effects for The Thing. He worked for more than a year without a day off and ended up in hospital from exhaustion. Stan Winston helped with one creature and asked that Bottin take the credit.
Why it mattered. Its gooey, impossible creatures are still held up as a high point of hand-made effects.
Crew of Twilight Zone: The MovieValencia, California
During night filming, a helicopter crashed after being hit by debris from special effects explosions. Actor Vic Morrow and two child actors, Myca Dinh Le and Renee Shin-Yi Chen, were killed. Afterwards studios and unions set up safety committees, safety bulletins and hotlines, and aviation rules were extended to film helicopters.
Why it mattered. Modern film sets treat safety as the first rule of any effect, partly because of this loss.
Kodak's colour negative 5293 of 1982 was rated 250 in tungsten light, and 5294 in 1983 reached 400. By 1989 the EXR 5296 stock was rated 500. The first Eastmancolor of 1950 had been rated about 16.
Why it mattered. Each doubling of film speed halves the light a scene needs, so crews could use smaller lamps and more natural light.
Normal 35 mm film left a strip at the side for the soundtrack. Super 35 used that space for picture too, an idea first tried in the 1950s Superscope format. Joe Dunton revived it in 1982, and it spread through the 1980s and 1990s.
Why it mattered. Most digital cinema sensors today are built to roughly this 'Super 35' size.
Mead, a former industrial designer, was the first person hired for Blade Runner. He started with vehicles and ended up designing streets, buildings and props. At the same time he designed for Tron, and he invented the screen credit visual futurist.
Why it mattered. It showed how one concept designer could shape a whole imagined future.
SmartKey was a set of keyboard shortcuts for word processors such as WordStar and WordPerfect. It is usually called the first screenwriting software. Writers no longer had to set every margin by hand for each character name and line of dialogue.
Why it mattered. Computers began to take care of the fiddly format so writers could focus on the story.
The pathologist Robin Warren saw curved bacteria in inflamed stomach linings, where experts said no germ could live. The young doctor Barry Marshall joined him, and in 1982 the cultures finally grew after plates were left over the long Easter weekend. The germ was named Helicobacter pylori.
Why it mattered. It opened the way to curing most ulcers with antibiotics.
The young doctor Barry Marshall joined Warren and tried to grow the bacteria. The cultures only succeeded when some plates were left over the long Easter weekend: the germ grows slowly. It was later named Helicobacter pylori.
Why it mattered. It gave the germ a name and let others test the claim.
Krishna Persaud and George DoddUniversity of Warwick, UK
Persaud and Dodd built a “model nose” from a few chemical sensors that each responded broadly to many smells. By comparing the pattern across sensors, it could tell different odours apart.
Why it mattered. It showed that a pattern from broadly tuned sensors is enough to tell smells apart, the same trick the real nose uses.
William DeVries and Robert JarvikUniversity of Utah, Salt Lake City, USA
Retired dentist Barney Clark received the Jarvik-7, a plastic and metal heart driven by air from a large machine beside his bed. He lived for 112 days.
Why it mattered. It proved a machine could replace a heart, and led to pumps that help people wait for transplants.
Session musician Charanjit Singh, who often played synthesizer for R.D. Burman, bought a new TB-303 and TR-808 and set Indian ragas to a disco beat, with a Roland Jupiter-8 playing melodies. The album Synthesizing: Ten Ragas to a Disco Beat sold poorly and was forgotten. When it was rediscovered and reissued in 2010, listeners heard squelchy 303 lines years before acid house.
Why it mattered. It is now seen as an early forerunner of acid house, made in Bombay.
Sagawa combined neodymium, iron and boron into Nd₂Fe₁₄B, the strongest permanent magnet ever made. He announced it in 1983; John Croat at General Motors found the same compound independently. Mass production followed within three years.
Why it mattered. Neodymium magnets made small, strong motors, headphones, hard drives and electric cars possible.
Thomas Rossing and William SykesNorthern Illinois University
Rossing and Sykes followed the tuning of a mridanga, a south Indian drum that shares the tabla's trick. They recorded its sound as more than 100 thin layers of paste were added. Step by step, the overtones moved into harmonic order.
Why it mattered. It showed exactly how the drum maker's patient layering creates the tuning Raman found.
15 August 1982; Asian Games from 19 November 1982 · No. 014 TVClear
India turns to colour
DoordarshanNew Delhi, India
Doordarshan broadcast Indira Gandhi’s Independence Day speech in colour on 15 August 1982. Colour broadcasts were started expressly for the Asian Games held in Delhi that November. The national channel, now DD National, also began that year.
Why it mattered. Colour and a national channel turned television into something the whole country shared.
B. Jayant Baliga, Akio Nakagawa and othersGeneral Electric, Schenectady, USA, and Toshiba, Japan
Baliga, who studied at IIT Madras, showed a working insulated-gate bipolar transistor at GE in 1982. It is as easy to control as a MOSFET but can handle much bigger currents. Nakagawa's team at Toshiba stopped it from ‘latching’ on, and Toshiba sold that design from 1985.
Why it mattered. IGBTs switch the big currents in large UPS systems, solar inverters and electric cars.
Carol Ginsberg and Delle Maxwell, MITCambridge, Massachusetts, USA
A performer wore a suit with LEDs on the joints. Two cameras with special light sensors each reported the 2D position of every LED, and a computer combined them into 3D points that drove a stick figure live.
Why it mattered. It was triangulation from two cameras driving a digital character, the core of optical mocap.
THX was launched with Return of the Jedi. It is not a sound format but a quality standard: a cinema that passes its tests plays a soundtrack the way the mixers heard it.
Why it mattered. It made the room itself part of the sound chain.
Wacom, founded by Azuma MurakamiAgeo, Saitama, Japan
Wacom was founded to make pen tablets. Its pens sense how hard you press, using magnetic signals from the tablet, so the pen needs no battery. In 1991 it made pens without a cord.
Why it mattered. Pressure-sensitive pens made drawing on a computer feel much more like drawing on paper.
Françoise Barré-Sinoussi and Luc MontagnierInstitut Pasteur, Paris
Barré-Sinoussi and Montagnier found a new virus in a lymph node from a patient. It was later named HIV, the human immunodeficiency virus. It infects helper T cells. They shared the 2008 Nobel Prize.
Why it mattered. Knowing the cause led to blood tests and, later, medicines that control HIV.
Dr Suresh Advani and teamTata Memorial Centre, Mumbai, India
Doctors in Mumbai gave a 9-year-old girl with leukaemia marrow from her younger brother. The transplant worked, and she lived more than 20 years without the cancer returning. Christian Medical College, Vellore, began its own programme in 1986.
Why it mattered. It brought marrow transplants, and the blood-making power of bones, into Indian medicine.
Howard Green's lab, with surgeons including Nicholas O'Connor and G. Gregory GallicoBoston, Massachusetts, USA
In 1983 two young brothers from Wyoming, Jamie and Glen Selby, were burned over more than 95% of their bodies. Howard Green's lab grew sheets of new skin from small patches of their unburned skin, and surgeons covered their wounds with it. Both boys survived, after cultured skin had first been tried on smaller burns in 1981.
Why it mattered. It showed that skin grown in a lab could save people who had almost none of their own left.
James Hardy, then Joel CooperJackson, Mississippi, USA, and Toronto, Canada
In 1963 James Hardy performed the first human lung transplant, but the patient lived only 18 days. Twenty years later Joel Cooper’s team in Toronto gave a single new lung to Tom Hall, who lived for years. Better drugs to calm the immune system made the difference.
Why it mattered. Transplants now give people with failing lungs a second chance.
Dave Smith (Sequential Circuits) and Ikutaro Kakehashi (Roland)NAMM show, Anaheim, California, USA
Rival companies agreed on one simple cable and code so any keyboard could play any other. At the NAMM show in January 1983, a Sequential Prophet-600 and a Roland Jupiter-6 talked to each other in public for the first time. In 2013 Smith and Kakehashi shared a Technical Grammy Award for creating MIDI.
Why it mattered. MIDI sends notes, not sounds, so keyboards, drum machines and computers can all play together.
Yamaha, using John Chowning's FM synthesisHamamatsu, Japan
Yamaha turned Chowning's FM idea into chips and built the DX7, with six operators, 16 notes at once and a memory for 32 sounds. Its glassy electric piano and bell sounds filled 1980s pop. Yamaha had hoped to sell about 20,000, but it sold about 200,000 in three years.
Why it mattered. It was the first digital synthesizer to be a huge commercial success.
Fuji launched Fuji Computed Radiography, which used a reusable imaging plate instead of film. The plate stores the X-ray pattern, a laser reads it out, and a computer tidies up the picture. Because the plate is so sensitive, it can work with smaller doses.
Why it mattered. It was the first big step from chemical film to digital X-ray pictures.
Atomic Energy Regulatory Board (AERB)Mumbai, India
The President of India set up the AERB under the Atomic Energy Act of 1962. It oversees the safe use of radiation across the country, including medical X-ray machines. Its mission is to make sure radiation does not cause undue risk to people or the environment.
Why it mattered. X-ray machines in Indian hospitals have a national safety regulator watching over them.
UA1 and UA2 teams, with Carlo Rubbia and Simon van der MeerCERN, near Geneva
Sheldon Glashow, Abdus Salam and Steven Weinberg had predicted that the weak force and the electromagnetic force are two faces of one force, carried by particles called W and Z. They shared the 1979 Nobel Prize. In 1983 CERN's collider found the W and then the Z.
Why it mattered. It confirmed the picture of four fundamental forces that explains every push and pull we know.
Historian Ruth Schwartz Cowan published More Work for Mother, a history of household technology. She argued that machines like the washer did not simply save time: people began to expect clean clothes far more often, and the work shifted onto mothers and wives.
Why it mattered. It showed that who does the washing is as important a question as how the machine works.
Department of Non-Conventional Energy Sources, Government of IndiaIndia
India launched the National Programme on Improved Chulhas to save firewood and get smoke out of kitchens. Improved stoves had better fireboxes and often a flue pipe. About 3.5 crore were installed by 2003, though many studies found families stopped using them.
Why it mattered. It was an early attempt to add a chimney to the village kitchen.
Yamaha; Dave Smith and Ikutaro KakehashiJapan and USA
In 1983 Yamaha launched the first Clavinova, the YP-40, a piano with no strings that made its sound with chips. That same year MIDI arrived, a shared digital language that lets keyboards and computers talk to each other.
Why it mattered. A digital piano never needs tuning, fits in a small flat and can plug into a computer.
The Centre for Development of Telematics was set up to design digital exchanges for Indian conditions: small, rugged rural exchanges (RAX) that could work in heat and dust without air conditioning, and larger ones for cities. Indian firms were licensed to make them.
Why it mattered. It put automatic telephones within reach of small towns and villages across India.
HP's ThinkJet (short for thermal inkjet) was the first low-cost, mass-produced thermal inkjet printer. The printhead was built into a throw-away ink cartridge, so each new cartridge brought fresh nozzles.
Why it mattered. Quiet, cheap inkjets began replacing noisy dot-matrix printers at home.
Hewlett-Packard, with a Canon print engineUSA and Japan
The first LaserJet printed 8 pages a minute at 300 dots per inch and cost $3,495. Inside was Canon's CX engine, with the drum and toner in one replaceable cartridge.
Why it mattered. Laser quality came to ordinary offices, and the desktop publishing boom followed.
Chuck Hull applied for a patent on stereolithography, which builds an object layer by layer by hardening liquid plastic with ultraviolet light. The patent was granted in March 1986.
Why it mattered. It started 3D printing: the idea of a printer that builds solid things.
Video Tape Associates, then da Vinci SystemsFlorida, USA
Engineers at a Florida post house called Video Tape Associates built a colour corrector called The Wiz from 1982. It could control a telecine and make primary and secondary colour changes, and fifteen were sold. In 1984 the team split off as da Vinci Systems, whose computer-controlled correctors were widely used with Rank Cintel telecines.
Why it mattered. It made colour correction a product you could buy, and gave the world the da Vinci name.
EditDroid used LaserDiscs and a computer to find shots quickly, with an early on-screen timeline. It was shown at the NAB trade show in 1984 but sold only a few systems.
Why it mattered. Many of its ideas, like the timeline, returned in later digital editors.
Vicon, Oxford Metrics (Julian Morris and team)Oxford, England, UK
Vicon's early camera systems were built for clinical gait analysis: measuring how children with cerebral palsy walk before and after surgery. Hospitals and universities helped set standard ways of placing markers.
Why it mattered. Medicine came first. The marker sets and methods that films use grew out of gait labs.
Cindy Goral, Kenneth Torrance, Donald Greenberg, Bennett BattaileCornell University, Ithaca, New York, USA
The Cornell team used a method called radiosity, borrowed from heat engineering, to work out how light bounces between dull surfaces. A red wall tints the floor next to it red, and their pictures showed it. They later built a real box with coloured walls so they could check the computer against photographs.
Why it mattered. It proved that light bouncing between surfaces, not just direct light, is what makes a room look real.
Rob Cook, Thomas Porter, Loren CarpenterLucasfilm Computer Division, California, USA
Instead of one perfect ray, they fired many slightly different rays for each pixel and averaged them. Spreading rays across time, a lens or a light gave motion blur, depth of field and soft shadows. It turned blurry, soft effects from a problem into a sampling job.
Why it mattered. Averaging many random samples is the idea behind every modern path tracer, and behind its noise.
John Lasseter and the Lucasfilm Graphics GroupSIGGRAPH, Minneapolis
The Adventures of André and Wally B. was a short cartoon made on computers. Lasseter, a Disney-trained animator, gave the shapes squash and stretch, and the team added motion blur so fast moves looked smooth.
Why it mattered. It proved computer animation could use the principles of hand-drawn cartoons.
Few believed that a germ causes stomach disease, and there was no animal model, so Marshall drank a culture of H. pylori himself. Within days he fell ill with a badly inflamed stomach, and a biopsy showed the bacteria had moved in.
Why it mattered. His daring experiment helped convince the world that ulcers can be caused by an infection.
About 45 tonnes of methyl isocyanate gas leaked from a pesticide factory at night and spread over the sleeping city. Thousands died within days, and estimates of the total deaths vary widely. Hundreds of thousands of survivors were left with damaged lungs and eyes.
Why it mattered. It is one of the worst industrial disasters ever, and a reminder that what we breathe can kill.
India's first renewable energy programme began installing solar water heaters on government buildings, first paid for in full and then with smaller subsidies. From 1991 the government switched to cheap loans through banks, and sales grew fast in states like Karnataka and Maharashtra.
Why it mattered. Help from the government and banks built India's solar water heater industry.
Hero Cycles (the Munjal family) and HondaDharuhera, Haryana, India
Hero, a bicycle maker, teamed up with Honda. Their first bike, the CD 100 of 1985, used a four-stroke engine that went far on a litre of petrol, at a time when many small bikes were thirsty two-strokes.
Why it mattered. It made fuel economy the thing Indian buyers cared about most.
Eureka Forbes, a joint venture of Forbes & Company and Electrolux, launched its Aquaguard water purifiers. Families who had only boiled or cloth-filtered water now had a machine on the wall that filtered it and killed germs with ultraviolet light. Aquaguard became so common that many people use the name for any purifier.
Why it mattered. It created the home water purifier market in India.
The World Health Organization published the first edition of its Guidelines for Drinking-water Quality. They give countries a science-based list of what can safely be in drinking water, from germs to chemicals.
Why it mattered. Many national standards, including India's, lean on these guidelines.
American Power Conversion (APC)Massachusetts, later Rhode Island, USA
Three engineers from MIT's Lincoln Lab founded APC in 1981 to work on solar power. When government solar funding dried up, they made their first UPS in 1984, the model 750, with a lead-acid battery inside. It kept personal computers and small networks running through blackouts.
Why it mattered. The UPS shrank from a room-sized machine to a box under a desk.
William Brastad, James Watkins and Golden Valley Microwave FoodsMinneapolis and Edina, Minnesota, USA
In 1981 a General Mills patent by Brastad described a very thin metal coating on film that turns microwaves into heat to brown food, now called a susceptor. In 1984 Golden Valley Microwave Foods launched Act II, the first mass-marketed microwave popcorn that could sit on a shelf, in a bag invented by the former Pillsbury engineer James Watkins.
Why it mattered. Popcorn, Spencer's first test food, became the snack most linked with the microwave.
Working on the GSM standard, Friedhelm Hillebrand typed out sentences and questions on a typewriter and counted: almost all fitted in 160 characters. That is exactly what fits in 140 bytes at 7 bits a letter.
Why it mattered. The limit shaped texting, and later tweets.
Cheap Group 3 machines, nearly all made in Japan, flooded offices. In the United States the number installed grew from about 500,000 in 1985 to about 5 million in 1990. Every new machine made the others more useful.
Why it mattered. By the end of the 1980s a fax number was printed on business cards next to the phone number.
For the advert Brilliance, the team filmed a real actress with reference points marked on her body, and a computer tracked those points to move a chrome computer-graphics robot.
Why it mattered. It was one of the first times captured human motion drove a CG character on television.
ILM and John Lasseter, for Young Sherlock HolmesCalifornia, USA
In one scene, a knight made of stained glass climbs out of a church window and attacks a priest. It was made entirely by computer and printed onto film with a laser. It is widely considered the first fully computer-made character in a feature film.
Why it mattered. It proved a computer could make a character, not just shapes and logos.
In Young Sherlock Holmes, a knight made of stained glass steps out of a church window and stalks a priest. It is usually credited as the first fully computer-generated character in a feature film.
Why it mattered. Computer characters could now share the screen with actors.
Hayao Miyazaki, Isao Takahata, Toshio Suzuki and Yasuyoshi TokumaKoganei, Tokyo
Ghibli became famous for hand-drawn films with painted backgrounds and careful acting, from My Neighbor Totoro to Spirited Away, while using computers only sparingly.
Why it mattered. It showed the world that hand-drawn animation could be art for every age.
Christopher VoglerWalt Disney Studios, Burbank, USA
Christopher Vogler, a story analyst at Disney, boiled Campbell's ideas down into a seven-page memo for screenwriters. Copies spread from studio to studio. He grew it into the book The Writer's Journey in 1992, with twelve stages and eight character types.
Why it mattered. It turned an old theory about myths into a practical checklist for film stories.
India expanded its 1978 Expanded Programme on Immunization into the Universal Immunisation Programme, covering six diseases at first. Today it offers free vaccines against 12 diseases to about 2.67 crore newborns and 2.9 crore pregnant women each year.
Why it mattered. It is one of the largest public health programmes in the world.
Robert Friedman, Darrell Rigel and Alfred KopfNew York, USA
Three doctors at New York University gave the public a simple checklist for spotting melanoma, a dangerous skin cancer: Asymmetry, Border, Colour and Diameter. An E, for a mole that is Evolving or changing, was added later.
Why it mattered. Anyone could now check their own skin, and melanomas caught early are far easier to treat.
Researchers from many countries met in Hawaii for the first international meeting on umami. Shizuko Yamaguchi showed with careful taste tests that umami could not be made by mixing the other four tastes, and "umami" was adopted as the scientific name for the taste of glutamate.
Why it mattered. It put umami on the world's scientific map, though its receptor was still unknown.
Brownell's team found that outer hair cells, taken out of the ear, get shorter and longer when their voltage changes. This electromotility is the engine of the cochlear amplifier.
Why it mattered. It explained how the ear boosts quiet sounds, and why Kemp heard echoes coming out.
Akira Yoshino, building on M. Stanley Whittingham and John B. GoodenoughKawasaki
Whittingham made the first lithium battery in the 1970s and Goodenough found a better cathode in 1980. Yoshino replaced the dangerous lithium metal with carbon, making a safe rechargeable cell; Sony sold the first ones in 1991.
Why it mattered. The battery in every phone and electric car.
Wayne Smith, Noel Davey and King JammyKingston, Jamaica
Singer Wayne Smith and his friend Noel Davey built a song on a rock rhythm preset from a small Casio MT-40 keyboard, a pattern programmed in Japan by Casio engineer Hiroko Okuda. Producer King Jammy finished the track, Under Mi Sleng Teng. It was Jamaica's first fully digital hit, and its riddim has backed hundreds of songs.
Why it mattered. A cheap home keyboard changed a whole country's music almost overnight.
Nusrat Fateh Ali Khan and Farrukh Fateh Ali KhanWOMAD festival, Mersea Island, England
Nusrat Fateh Ali Khan's qawwali group sang for hours at the WOMAD festival in 1985, and it launched his world career. His brother Farrukh played lead harmonium in the group for more than 25 years. Fans in England called him the King of the Harmonium.
Why it mattered. Millions of people around the world first heard the Indian harmonium through qawwali.
A light bike with a 98 cc two-stroke engine that was quick for its size. Production ended in 1996 as emission rules tightened, but it is still a cult favourite.
Why it mattered. It showed a small commuter could also be fun, and why cleaner four-strokes eventually won.
Yoshino paired Goodenough's cathode with a carbon anode made from petroleum coke. Lithium ions shuttle between the two sides, and there is no raw lithium metal to catch fire. It was the first commercially practical lithium-ion design.
Why it mattered. It is the basic recipe of almost every lithium battery today.
Joe Farman, Brian Gardiner and Jon ShanklinBritish Antarctic Survey, Halley station, Antarctica
Measurements from Antarctica showed that ozone over the South Pole was dropping sharply every spring. The scientists linked the losses to chlorine from CFCs. The next year Susan Solomon led an expedition that helped explain how icy polar clouds speed up the damage.
Why it mattered. Seeing a real hole made the danger impossible to ignore.
John Canny worked out, with careful maths, what a good edge detector should do: find real edges, place them exactly, and mark each only once. His method is still built into image software today.
Why it mattered. Hand-designed edge finding was the first step in most vision systems for decades.
David Rumelhart, Geoffrey Hinton and Ronald WilliamsSan Diego and Pittsburgh, United States
A short paper in Nature showed that backpropagation could train networks with hidden layers, and that those layers learned useful features by themselves. They did not invent the method, which had earlier roots, but they made it popular.
Why it mattered. Multilayer networks could finally be trained, and the XOR problem stopped being a wall.
Jim Kajiya (and, independently, David Immel and colleagues)Caltech, Pasadena, USA (SIGGRAPH 86)
Kajiya wrote down a single equation: the light leaving a point is the light it gives off plus all the light arriving from every direction and bouncing back out. He also showed how to estimate it by following random paths of light. A team from Cornell described the same idea at the same conference.
Why it mattered. Path tracing, used in films and games today, is a way of solving Kajiya's rendering equation.
Pixar became its own company in February 1986, bought from Lucasfilm by Steve Jobs. In August it showed Luxo Jr., two minutes of a parent desk lamp and a child lamp playing with a ball. The audience went wild.
Why it mattered. It was the first computer-animated film nominated for an Oscar, and it made people care about computer characters.
Dr Indira Hinduja, with T. C. Anand Kumar's ICMR teamMumbai, India
A baby boy named Harsha was born at KEM Hospital in Mumbai after IVF by Dr Indira Hinduja and a team from the Indian Council of Medical Research's Institute for Research in Reproduction.
Why it mattered. It started IVF as a medical service in India, which now has thousands of fertility clinics.
Suniti Solomon and her student Sellappan NirmalaMadras (Chennai)
Dr Suniti Solomon and her student tested blood samples in Madras and found India’s first confirmed HIV infections. Solomon went on to set up care and counselling for people with HIV and fought the stigma around it.
Why it mattered. It started India’s response to HIV, which now includes free treatment for everyone who needs it.
Scientists put the gene for one hepatitis B protein into yeast, which then made the protein in huge amounts. The new vaccine needed no human blood. Licensed in 1986, it was the first vaccine made with genetic engineering, and vaccines like it are still used today.
Why it mattered. A cheap, safe vaccine made it possible to vaccinate babies all over the world.
Institute of Nuclear Medicine and Allied Sciences (INMAS, DRDO)Delhi, India
The first MRI scanner in India was installed at INMAS in Delhi; sources give 1986 or 1987. AIIMS in New Delhi got its first clinical 1.5 T scanner in 1993.
Why it mattered. It began MRI for patients in a country where scanners are now found in cities across the country.
Le Bihan showed how to make MR images of diffusion, the random wandering of water molecules. In 1994, with Peter Basser at the US National Institutes of Health, he introduced diffusion tensor imaging, which measures the direction water moves most easily.
Why it mattered. Diffusion scans now spot strokes within minutes and trace the brain’s wiring.
Gerd Binnig, Calvin Quate and Christoph GerberIBM and Stanford, United States
The atomic force microscope drags a sharp tip on a tiny cantilever over a surface. The forces from single atoms bend the cantilever, and Hooke's law turns the bend into a force.
Why it mattered. Hooke's law became a way to see and weigh forces between individual atoms.
Georg Bednorz, Alex Müller; Paul Chu's teamZurich, Switzerland; Houston, USA
At IBM Zurich, Bednorz and Müller found a copper-oxide ceramic that superconducts at about 35 K. Within a year Chu's group made YBCO, which works at about 93 K, above the boiling point of cheap liquid nitrogen.
Why it mattered. Zero-resistance wires moved from rare physics labs towards MRI machines and power cables.
Department of Telecommunications and booth ownersAcross India
Yellow STD/ISD/PCO booths spread to street corners, shops and villages, often run by young entrepreneurs and people with disabilities. For the first time, millions of people without a home phone could dial any city, or any country, themselves. Mobile phones made them rare by the 2010s.
Why it mattered. Public phones brought long-distance calling to ordinary people and created many small businesses.
Canon is credited with the first plain-paper fax machine, printing with a laser engine instead of on thermal paper. Plain-paper machines took over in the 1990s.
Why it mattered. Faxes no longer curled up or faded in a drawer.
Larry Hornbeck invented the digital micromirror device, a chip covered in hundreds of thousands of aluminium mirrors, each about 16 micrometres wide. Each mirror tilts about 10 to 12 degrees to send light to the screen or away from it, switching thousands of times a second. It became the heart of DLP projectors, and in 2015 Hornbeck received an Oscar for it.
Why it mattered. Each mirror is one pixel, so a film could become pure data with no film strip at all.
Frieder Hochheim and Gary Swink; Robby MüllerLos Angeles, California
On the film Barfly, the cinematographer Robby Müller needed light in a room too cramped for normal lamps. Gaffer Hochheim and best boy Swink built bright fluorescent tubes with a separate ballast, small enough to tape to a wall. They founded Kino Flo that year and won a technical Academy Award in 1995.
Why it mattered. Cool, flat tube lights made soft light easy to hide in tight real places.
Kunkel's team found the gene behind Duchenne muscular dystrophy in 1986, and in 1987 identified its protein, dystrophin, which anchors the inside of each fibre to its outer membrane. Boys with the disease lack it.
Why it mattered. It turned a disease described in the 1860s into a target for treatment.
The first commercial DXA scanner, the QDR-1000, swapped the radioactive source for an X-ray tube shooting two energies. Comparing how each is absorbed gives bone density quickly, with a low dose. A result called the T-score compares you with a healthy young adult.
Why it mattered. It became the standard test for weak bones around the world.
Benabid found that steady high-frequency pulses from an electrode deep in the brain could calm a tremor without destroying tissue. It is now used for Parkinson’s disease and some other conditions.
Why it mattered. A pacemaker for the brain, switchable and adjustable.
Svetlana Mojsov, Joel Habener, Daniel Drucker; Jens Juul HolstBoston, USA, and Copenhagen, Denmark
Mojsov and Habener identified the active form of GLP-1, a hormone from the lower gut, and with Drucker showed it boosts insulin. Holst’s team in Copenhagen found the same independently. Drugs that copy it now treat diabetes and obesity.
Why it mattered. It showed that a gut hormone helps control blood sugar and appetite, and led to a new family of medicines.
G. Raj Narayan, Radel ElectronicsBangalore (Bengaluru)
Raj Narayan was an engineer and a flute player who started Radel in a garage in Bangalore in 1979. In 1987 he showed the Taalmala, an electronic tabla that plays rhythm cycles, by using it to accompany a flute recital. Radel says it was the first such instrument to use software and microprocessors.
Why it mattered. Students everywhere could now practise with a tabla beat at home, even without a drummer.
Early gantries were connected by cables, so they had to stop and turn back after every slice. Slip rings pass power and data through sliding contacts, so the ring can spin continuously. Siemens' SOMATOM Plus turned once a second, then the fastest CT in the world.
Why it mattered. Continuous spinning made the next big idea, the spiral scan, possible.
Countries agreed to phase out the chemicals that destroy ozone, starting with CFCs. It became the first treaty ratified by every UN member state. Fridges switched from CFC-12 to HFC-134a, which does not harm ozone but traps heat, and later to gases such as isobutane.
Why it mattered. It is widely seen as the most successful environmental treaty ever, and the ozone layer is slowly healing.
Ramayan began on Sunday mornings on Doordarshan and ran for 78 episodes. Estimates of its peak audience run from 80 to 100 million people. Streets emptied and shops closed while it was on.
Why it mattered. It showed how one screen in a room could gather a whole nation at the same moment.
Ching W. Tang and Steven Van Slyke, Eastman KodakRochester, New York, USA
Two Kodak chemists built the first practical OLED: thin layers of carbon-based material that glow when a current flows. Each dot makes its own light, so no backlight is needed. Tang was born in Hong Kong.
Why it mattered. It is the ancestor of the OLED screens in today’s best TVs and phones.
Miele launched its first dishwasher with a cutlery tray, a shallow third level above the baskets. Knives, forks and spoons lie flat and get washed on their own level.
Why it mattered. Better loading means better cleaning, because water can reach every surface.
Kafka, a food writer who had not used a microwave until 1984, published ‘Microwave Gourmet’. It showed serious cooks that the oven could do much more than reheat leftovers, even though many food lovers were horrified.
Why it mattered. It helped turn the microwave from a reheating box into a cooking tool.
Countries agreed to phase out the chemicals that destroy ozone, starting with CFCs. It became the first treaty ratified by every UN member state. Air conditioners switched from CFCs to HCFCs like R-22, and later to gases with no chlorine at all.
Why it mattered. It is widely seen as the most successful environmental treaty ever, and the ozone layer is slowly healing.
Benveniste's team reported that antibody solutions diluted far past 12C still affected blood cells. Nature published it with a warning, then sent a team that watched the tests repeated blind: the effect vanished. Later labs could not repeat it either.
Why it mattered. It remains the best-known attempt to show how a remedy with no molecules could act.
Chris Harris and Mike StephensPlessey Research, Roke Manor, United Kingdom
Harris and Stephens described a corner detector that looks for places where the picture changes in two directions at once. Corners are easy to find again in another photo, so they help match and track things.
Why it mattered. Chapter 2's corner filter uses their formula.
AT&T, France Télécom and British TelecomUSA, UK and France
TAT-8, the first transatlantic fibre-optic cable, carried calls as flashes of light, with about 40,000 circuits by most accounts. Fibre soon replaced copper and satellites on the world's busiest routes.
Why it mattered. Glass fibre gave calls, and then the internet, almost unlimited room.
Pixar (Pat Hanrahan, Rob Cook, Loren Carpenter, Ed Catmull and others)Pixar, California, USA
Pixar presented the RenderMan Interface, a common language for describing scenes, cameras and lights to a renderer. It included a shading language so artists could write their own materials. Pixar's renderer was built on the Reyes method, which chopped surfaces into tiny pieces smaller than a pixel.
Why it mattered. Programmable shaders let artists invent any material they could describe.
Oga was art director on Studio Ghibli's My Neighbor Totoro. His painted backgrounds of fields and forests gave the film its warm, living feel. In 2007 a Tokyo museum held a show about him called The Man Who Drew Totoro's Forest.
Why it mattered. Background painting and art direction can make a place feel like a character.
For Star Trek V: The Final Frontier, the animator Lynda Weinman used a desktop program called Swivel 3D to make simple moving models of the starship Enterprise. It is described as the first 3D computer previs for a major film. Planners could now try camera moves in three dimensions.
Why it mattered. Storyboards began to leave paper and move into the computer.
Omeprazole, sold as Losec, went on sale in Sweden in 1988. It blocks the H⁺/K⁺-ATPase, the proton pump that parietal cells use to make acid. It became one of the best-selling medicines ever.
Why it mattered. Doctors gained a powerful way to reduce acid for reflux and ulcers.
Jeffrey Corwin and Douglas Cotanche; Brenda Ryals and Edwin RubelUSA
Two teams showed that young birds regrow hair cells after damage from loud noise, and later work found their hearing largely comes back. Humans and other mammals cannot do this.
Why it mattered. It started the search for ways to help human hair cells grow back, still unsolved.
Bath patented the Laserphaco Probe, a device that uses a laser to break up a cataract before it is removed. She was the first Black woman doctor to receive a US patent for a medical invention, and co-founded the American Institute for the Prevention of Blindness.
Why it mattered. Her work helped make cataract surgery gentler and campaigned for eye care as a right.
The M1 mixed short recorded samples of real instruments with synth filters, effects and a built-in sequencer. This kind of all-in-one keyboard became known as a workstation. About 250,000 were sold, and its piano and organ sounds were all over 1990s house music.
Why it mattered. It is often called the best-selling synthesizer ever, and it put a small studio inside one keyboard.
BMW offered an electronic anti-lock braking system on the K100, the first on a production motorcycle. Sensors watched the wheels, and a pump eased the brake whenever a wheel began to lock.
Why it mattered. It made hard braking much safer, and it is now the law on bigger bikes in India and many other countries.
Schering (Magnevist)Berlin, Germany; approved in the USA
Gadopentetate dimeglumine, sold as Magnevist, was approved in the United States as the first gadolinium contrast agent for MRI. Injected into a vein, it shortens T1 and makes some tumours and inflamed areas stand out.
Why it mattered. Contrast agents made MRI better at finding disease that plain scans miss.
Malhotra, an electronics engineer from Jadavpur University, started Luminous with about Rs 40,000 of savings, four people and 600 square feet of space. It first made power backups for computers, then home inverters from 1994. In 2011 Schneider Electric bought a 74% stake.
Why it mattered. Indian companies designed inverters for Indian homes, with long, frequent power cuts.
Most ovens make ‘half power’ by switching the magnetron fully on and off every few seconds. Panasonic's inverter used electronics to run the magnetron at a steady lower power instead. The first model gave up to 700 W.
Why it mattered. Steady, gentle power heats food more evenly, and many ovens now work this way.
Chemists measured lead in kushtas, traditional preparations made by strongly heating metals and minerals, used in Unani and Ayurvedic practice in the subcontinent. Several contained large amounts.
Why it mattered. It showed that some traditional preparations can carry toxic metals.
Yann LeCun and colleaguesAT&T Bell Labs, Holmdel, United States
Yann LeCun's team trained a convolutional network with backpropagation to read handwritten digits on US mail. The same small filters were shared across the whole picture, so it needed far fewer weights.
Why it mattered. It showed that a network could learn its own filters from examples, instead of people designing them.
Yann LeCun and colleaguesAT&T Bell Labs, Holmdel, United States
Yann LeCun's team trained a convolutional network with backpropagation to read handwritten digits on US mail. The network shared the same small filters across the whole image, so it needed far fewer weights.
Why it mattered. It showed that learned networks could beat hand-written rules at reading real, messy handwriting.
George CybenkoUniversity of Illinois, United States
Mathematician George Cybenko proved that a network with one hidden layer, if it is wide enough, can get as close as you like to any smooth pattern. Others proved similar results the same year.
Why it mattered. It explained why networks are so flexible, and also why they can memorise noise if you are not careful.
Scott Crump filed a patent on building objects from melted plastic squeezed out of a moving nozzle, laying down one layer on top of another. The same year he and his wife Lisa founded the company Stratasys to sell the machines.
Why it mattered. FDM is the kind of 3D printer found in schools and homes today.
Avid showed its computer editing system in 1989. Editors could cut with digitised copies of the footage, then send a list of their decisions to finish the film.
Why it mattered. Media Composer became the standard for feature films and TV, and it still is in many cutting rooms.
Saluja, a Film and Television Institute of India graduate, won the National Film Award for editing for Parinda, then again for Dharavi, Sardar and Godmother. She also cut Jaane Bhi Do Yaaro and 1942: A Love Story.
Why it mattered. She became one of Indian cinema's most respected editors when the job was mostly done by men. An editing award is now named after her.
In The Abyss a tube of seawater snakes through an underwater base and copies the faces of the actors. ILM spent about six months making 75 seconds of computer graphics for it. The film won the Oscar for visual effects.
Why it mattered. It was ILM's first 3D computer character that showed emotion, and it convinced film makers that computers were nearly ready.
Industrial Light & Magic (ILM), for James CameronCalifornia, USA
In The Abyss, a snake-like column of sea water explores an underwater base and copies the actors' faces. ILM built it on computers, and the team nicknamed it the water weenie. The film won the Oscar for visual effects.
Why it mattered. Making something clear, shiny and bending light proved computers could render tricky materials for film.
John Lasseter and William Reeves, PixarHollywood, California
Tin Toy (1988), about a wind-up toy running from a baby, won the Academy Award for Best Animated Short Film. The year before, Pixar had published the RenderMan interface, and its renderer went on to be used on countless films.
Why it mattered. Computer animation was now accepted as an art form.
Park finished A Grand Day Out, the first Wallace & Gromit film, which he had started as a student. His Creature Comforts, with clay animals voiced by real people, won the Academy Award for animated short in 1991.
Why it mattered. Clay animation became a comedy style loved around the world.
Digidesign: Evan Brooks and Peter GotcherCalifornia, USA
Digidesign's Sound Tools (1989), and then Pro Tools (1991), let editors record, cut and mix sound on a computer screen, with any cut undoable. Within a decade most film sound was edited this way.
Why it mattered. Layering hundreds of tracks became quick and cheap.
Rosenberg proposed the word sarcopenia, from Greek for "poverty of flesh", for the loss of muscle with age. The next year a study showed people in their 90s could nearly triple their strength with 8 weeks of training.
Why it mattered. It made muscle loss something doctors measure and treat.
Silvano Raia; Russell StrongSão Paulo, Brazil, and Brisbane, Australia
In December 1988, Silvano Raia's team in Brazil gave a child part of an adult's liver, but the child lived only six days. In 1989, Russell Strong in Brisbane transplanted part of a mother's liver into her baby son, and both did well.
Why it mattered. Because the liver regrows, a living parent can now save a child without waiting for a donor who has died.
Qui-Lim Choo, George Kuo, Daniel Bradley and Michael HoughtonChiron (California) and the CDC, USA
Harvey Alter had shown in the 1970s that an unknown virus was causing hepatitis after blood transfusions. Houghton's team at Chiron copied genes from infected blood into bacteria and used patients' antibodies to fish out the virus's genes. They named it hepatitis C virus and published in 1989.
Why it mattered. Blood banks could now test for it, making transfusions far safer.
Kalender, Seissler and Vock showed the first clinical spiral CT at the RSNA meeting in Chicago: the table moved steadily while the tube spun, and software rebuilt slices at any position. A whole chest could be scanned in one breath-hold.
Why it mattered. Every modern CT scan is a spiral scan.
In 1989 the Japanese company Rinnai applied for a patent on an oven heated by bright halogen lamps. Through the 1990s and 2000s, round glass bowl ovens with a lamp and a fan in the lid were sold on TV shopping channels. Exactly who made the first one is unclear.
Why it mattered. They mixed glowing radiant heat with a fan, very like an air fryer in a glass bowl.
Gandhimathi Appliances, set up in 1986, first made LPG stoves and water heaters and began making Butterfly mixer grinders in October 1989. More and more Indian brands joined in, so buyers had plenty of choice.
Why it mattered. Competition pushed prices down and put a mixie within reach of many more homes.
In the 1980s Indian companies such as Videocon began selling televisions and washing machines to middle-class families buying them for the first time. In 1989 IFB signed an agreement with Bosch-Siemens to make fully automatic washing machines in India. Samsung and LG arrived in the mid-1990s, and cheaper semi-automatic twin tubs and fully automatic machines spread in cities.
Why it mattered. India became one of the world's big washing machine markets, though most homes still wash by hand.
Peter Brown, Robert Mercer and colleagues at IBMYorktown Heights, United States
IBM's team translated French to English using statistics learned from Canadian parliament records in both languages, with no hand-written grammar. A language model scored how natural each English sentence was.
Why it mattered. Statistical translation proved that learning from lots of text could beat rules.
From the late 1980s, yellow STD/ISD/PCO booths spread across India, run by local shopkeepers. One count put the booths at over 12 lakh (1.2 million) in the early 2000s. Many also offered fax, so small traders could send order forms and documents without a line of their own. Mobile phones emptied them after about 2008.
Why it mattered. For millions of Indians the neighbourhood booth was their first fax machine, as well as their first long-distance phone.
For the scene where people walk behind an airport X-ray scanner, the team recorded the actors with motion capture to animate glowing CG skeletons. Accounts differ on how much of the capture data ended up in the final shots.
Why it mattered. It is often named as an early feature-film use of motion capture.
Disney and Pixar (CAPS)Burbank and Richmond, California
The Computer Animation Production System scanned pencil drawings and coloured them on screen, with digital multiplane moves. It was used for one shot of The Little Mermaid (1989), then for all of The Rescuers Down Under (1990). Disney stopped using cels.
Why it mattered. Digital ink and paint ended the cel era and won a Scientific and Engineering Academy Award in 1992.
Thomas Knoll wrote a program to show and change pictures while he was a student. His brother John, who worked at the effects studio Industrial Light & Magic, pushed him to grow it. Adobe released it as Photoshop 1.0 in February 1990.
Why it mattered. Layers of changeable digital paint later became the everyday tool of concept artists.
Madnick and Cahan founded Final Draft to build a word processor that formats a script to Hollywood's rules automatically. It became the industry's standard tool for film and television scripts. In 2013 it won a Primetime Emmy Engineering Award.
Why it mattered. The standard page layout was now built into the software writers used every day.
Paul Lauterbur, Peter Mansfield, Seiji Ogawa and othersUSA, UK and Japan
MRI grew from 1970s experiments into scanners that show the brain and spinal cord in sharp detail without X-rays. In 1990 Seiji Ogawa showed MRI can also track where blood oxygen changes, so functional MRI can see which areas are busy.
Why it mattered. Doctors can now see strokes, tumours and cord injuries inside a living person.
Pallikaris lifted a thin flap of cornea and reshaped the tissue beneath with an excimer laser. He first tried it on a blind eye in 1989 and on sighted eyes in 1990, and named it LASIK.
Why it mattered. Changing the cornea's curve changes the eye's main lens, so millions no longer need glasses.
Seiji Ogawa and colleaguesAT&T Bell Laboratories, New Jersey, USA
Ogawa showed that MRI can detect changes in blood oxygen in the brain, the BOLD signal. Busy brain areas get extra oxygen-rich blood, so scanners can map which parts work during a task. This became functional MRI.
Why it mattered. fMRI lets scientists watch healthy human brains at work without surgery.
Seiji Ogawa and colleaguesMurray Hill, New Jersey, USA
At AT&T Bell Laboratories, Ogawa showed in rats that the amount of oxygen in blood changes the MR signal near vessels. He called it blood-oxygen-level-dependent (BOLD) contrast.
Why it mattered. BOLD is the signal behind almost every fMRI study of the working brain.
Douglas Rothman, Gerald Shulman and colleaguesNew Haven
Using magnetic resonance, the team measured liver sugar stores in people fasting for 68 hours. New glucose made by the liver supplied 64% of blood sugar in the first 22 hours and 96% later on.
Why it mattered. It showed exactly how the body keeps blood sugar steady without food.
When India could not buy a big American supercomputer, the government set up C-DAC in 1988 to build one. Its answer, PARAM 8000, linked many small processors to work in parallel. It was rated at about 1 gigaflop, a billion calculations a second, at its peak.
Why it mattered. It proved that many small processors working together could match a costly supercomputer.
Tim Berners-Lee proposed a way to link documents across computers in 1989. By 1991 the web was open to people outside CERN, and in 1993 CERN put the software into the public domain.
Why it mattered. It turned computers from calculating machines into windows onto the world.
Finland's former prime minister Harri Holkeri made the first call on a GSM network, built by Nokia and Siemens for the operator Radiolinja. GSM was digital: voice became numbers, encrypted over the air.
Why it mattered. GSM became the world's standard, and the one India adopted.
Adobe Premiere let people edit video on an ordinary Apple Macintosh computer. Today's Premiere Pro is used for everything from YouTube videos to feature films.
Why it mattered. Editing software stopped being only for studios.
ILM and Dennis Muren, for Terminator 2California, USA
The T-1000 villain could melt, flow through bars and reshape itself. Up to 35 ILM artists made about five minutes of it, in roughly 42 computer shots. Rendering was so slow that 15 seconds could take ten days.
Why it mattered. It showed computers could make a main character that shared the screen with real actors.
Terminator 2 featured the T-1000, a villain made of shiny liquid metal that could reshape itself. Its computer-made effects appeared in about 42 or 43 shots, alongside many practical effects. It won the Oscar for visual effects.
Why it mattered. A reflective chrome body had to mirror the real set around it, a hard rendering test.
In Terminator 2: Judgment Day, a shape-shifting robot pours through bars and rises from a floor. ILM built on its watery creature from The Abyss (1989) to make a CG character that moved like a real person.
Why it mattered. It showed that CG could make things no camera could film.
Painter was made to copy real materials like watercolour, oils, chalk and charcoal on textured paper. With a pressure pen, its brushes respond to how you press and tilt. It is now sold by Corel.
Why it mattered. Artists could keep their painting skills and still work digitally.
Linda Buck and Richard AxelColumbia University, New York, USA
Buck and Axel discovered a huge family of genes for odorant receptors, proteins on the cilia of smell neurons. In mice there are about 1,000; humans have about 400 that work. They showed each neuron uses just one receptor type.
Why it mattered. It explained, at last, how the nose can detect so many different molecules.
For a long time the tabla was played almost only by men. Aban Mistry of Mumbai was among the first women to become a tabla maestro, and she was honoured after her death in 2018. In 1991 the Limca Book of Records listed Anuradha Pal as the first professional female tabla player, and in 1996 she started an all-women band called Stree Shakti.
Why it mattered. They opened a door that many young women drummers have walked through since.
NASA Jet Propulsion LaboratoryOn the way to Jupiter
The Galileo spacecraft tried to open its 4.8 m umbrella-like antenna, but two or three of its 18 ribs stayed stuck. Investigators blamed friction at metal pins whose dry lubricant had been worn away during testing and travel.
Why it mattered. In space, a little too much friction can cripple a mission.
Live CNN coverage of the Gulf War in early 1991 showed Indian viewers what satellite TV could do. Star TV began beaming channels over Asia from the AsiaSat 1 satellite, and Zee TV, the first private Hindi channel, launched in October 1992. Local cable operators strung wires from dishes to homes.
Why it mattered. Doordarshan was no longer the only channel, and cable spread fast.
Fisher & Paykel introduced its SmartDrive top-loader, with a brushless electric motor that drove the agitator directly. Electronics made the same motor both wash and spin, so it needed no belt, gearbox or clutch.
Why it mattered. Fewer moving parts meant quieter machines that last longer and waste less energy.
The ADXL50 was the first mass-produced MEMS accelerometer: a microscopic mass on silicon springs, built into a chip. When a car crashes, the mass moves against its springs and the chip fires the airbag.
Why it mattered. The same tiny spring-and-mass idea now sits in phones, watches and game controllers.
Sony began selling the world's first rechargeable lithium-ion batteries, based on Yoshino's design. They were light and held a lot of energy, perfect for camcorders, then phones and laptops.
Why it mattered. Lithium-ion began its journey from gadgets to cars to home backup batteries.
Kodak fitted a 1.3 megapixel sensor to a Nikon F3 body, wired to a separate storage unit. It was made for press photographers and cost tens of thousands of dollars.
India's DoT invited bids for private paging services in 27 cities, with up to four operators in the largest. Disputes and clarifications delayed the launch by about three years.
Why it mattered. It was one of India's first steps in opening telecoms to private companies.
Engineer Neil Papworth typed "Merry Christmas" on a computer and sent it to the phone of Vodafone director Richard Jarvis. Phones could not yet type texts back.
Why it mattered. SMS grew into the most used data service in the world for twenty years.
Kodak's Cineon system scanned film into computer files, 10 bits per colour. Instead of storing light in straight steps, it stored it on a log curve, like the density of the negative. In 1993 it was used to scan and restore Disney's Snow White at 4K.
Why it mattered. Log files, the flat grey footage colourists start from, trace back to Cineon.
Batman Returns was the first film released with Dolby Digital: 5.1 channels of compressed digital sound printed as blocks between the sprocket holes of the film. DTS (Jurassic Park, 1993) played its sound from a CD kept in step by timecode on the print.
Why it mattered. Clean, discrete 5.1 sound became the cinema standard of the 1990s.
Doctors in Brussels reported the first pregnancies after injecting a single sperm directly into an egg with a very fine glass needle. The method is called ICSI.
Why it mattered. It helped many couples where the male partner has very few sperm.
India renamed its goitre programme the National Iodine Deficiency Disorders Control Programme. The new name showed that lack of iodine harms far more than the neck: it can slow a child's growth and learning. The goal became iodised salt for everyone, called universal salt iodisation.
Why it mattered. It turned a programme for a few hill areas into a plan for every kitchen in India.
A.R. Rahman loved the synthesizer as the ideal mix of music and technology, and made advertising jingles in a small studio behind his home in Chennai. Director Mani Ratnam asked him to score the Tamil film Roja. Rahman blended electronic sounds with Indian and Western instruments, and Time magazine later listed Roja among the 10 best soundtracks of all time.
Why it mattered. It showed a new generation in India that a home studio full of electronics could make music for millions.
Mickey Hart, with Zakir Hussain and othersNew York City
Grateful Dead drummer Mickey Hart made the album Planet Drum with percussionists from India, Nigeria, Puerto Rico and Brazil. Zakir Hussain played tabla on it. It won the very first Grammy for Best World Music Album.
Why it mattered. It put the tabla at the centre of a new idea: a global conversation between drums.
Peter Bandettini, Kenneth Kwong, Seiji Ogawa and teamsMilwaukee, Boston and Minneapolis, USA
Three groups published within weeks of each other in 1992, showing the human visual and motor cortex lighting up as people looked at flashing lights or moved their fingers.
Why it mattered. It opened a new science of mapping human thought without surgery or radiation.
Peter AgreJohns Hopkins University, Baltimore, USA
Peter Agre's team found a protein in red blood cell membranes that forms a pore just for water. Cells with it swelled and burst in dilute solution; cells without it did not. These aquaporins are how the kidney's water channels work under the control of ADH.
Why it mattered. It explained how water crosses cell membranes so fast, and won the 2003 Nobel Prize in Chemistry.
Inspired by the epidemiologist Archie Cochrane, a group of researchers set out to find every fair trial on each health question, combine them and keep the answers up to date. Its South Asia centre is at CMC Vellore.
Why it mattered. Systematic reviews made it harder for one lucky trial, or an unpublished dull one, to mislead doctors.
Motorola announced FLEX, a paging code that could send up to 6,400 bits a second using four-level FSK, with a 4-minute cycle of 128 frames so pagers could sleep even longer.
Why it mattered. Faster codes let one channel serve millions more pagers.
ILM, Phil Tippett and Stan Winston, for Jurassic ParkCalifornia, USA
The dinosaurs were first planned as stop-motion puppets, until ILM's computer tests won the day with less than a year to go. The film has only about six minutes of computer dinosaurs, cut together with about nine minutes of life-size robot puppets. Tippett's animators steered the digital dinosaurs using sensor-fitted puppets.
Why it mattered. After Jurassic Park, film makers knew almost anything could be made in a computer and look real.
Jurassic Park mixed life-size robot dinosaurs with computer-made ones for many of the running and chasing shots. Its computer imagery is widely seen as a turning point for visual effects. It won the Oscar for visual effects.
Why it mattered. It convinced film makers that computer-rendered creatures could look alive.
Jurassic Park mixed life-size animatronic dinosaurs with computer-generated ones. The CG dinosaurs are on screen for only a few minutes, but they moved like real animals, animated by artists guided by stop-motion expert Phil Tippett.
Why it mattered. After it, studios moved from models and stop motion to CG creatures (see StopMotionClear).
Stan Winston Studio, for Steven SpielbergUniversal Studios, California
Stan Winston's team built a full-size robotic T. rex, about 40 feet long and reported to weigh around 9,000 pounds, moved by powerful hydraulics under latex skin. It shared the screen with new computer-made dinosaurs from ILM. The robot was used for close shots, and the computer dinosaurs for running and full-body shots.
Why it mattered. Jurassic Park showed that real robots and CGI work best together.
Steven Spielberg; ILM; Stan Winston StudioCalifornia
Jurassic Park mixed life-size animatronic dinosaurs with dinosaurs made entirely in the computer. The digital animals looked real in daylight, among real actors.
Why it mattered. It convinced film-makers that computer graphics could show almost anything.
Greenpeace and Foron (formerly DKK Scharfenstein)Eastern Germany
In 1992 Greenpeace brought together scientists and Foron, a struggling fridge maker in the former East Germany, to build a fridge that used hydrocarbons such as isobutane for both its cooling gas and its insulation foam. About 70,000 people pre-ordered one, the first came off the line on 15 March 1993, and within a year most European makers had followed.
Why it mattered. Hydrocarbon fridges, free of ozone-harming and high-warming gases, now number around a billion, says Greenpeace.
Eric Fossum and teamNASA Jet Propulsion Laboratory, California, USA
Fossum's team developed the CMOS active-pixel sensor, which amplifies each pixel on the chip itself and can be made with ordinary chip-making processes.
Why it mattered. Cheap, low-power CMOS sensors are in almost every camera and phone today.
Masahiro Hara and team at Denso WaveDenso Wave, Japan
Engineers at Denso Wave, a Toyota group company, designed the QR code to track car parts. Its three big corner squares can be found quickly from any angle, and built-in error correction fixes damaged parts.
Why it mattered. Decades later, QR codes carry UPI payments in India, and reading them still needs no neural network.
A maths professor found that Intel's Pentium chip sometimes divided wrongly, from the fifth significant digit on, because a few entries were missing from a lookup table inside the chip. 4,195,835 ÷ 3,145,727 came out as 1.333739… instead of 1.333820… Intel replaced chips and took a $475 million charge.
Why it mattered. Even a tiny error in arithmetic hardware can be very costly, so chips are now checked with mathematical proofs.
The IBM Simon Personal Communicator went on sale. It had a touchscreen, email, a calendar and apps, which is why it is often called the first smartphone. Its battery lasted about an hour.
Why it mattered. It showed a phone could also be a pocket computer.
Epson's Stylus Color was the world's first 720 dpi colour inkjet. It used Epson's Micro Piezo head, which squeezes drops out with a bending crystal instead of boiling them.
Why it mattered. Home printers could now print photographs people were happy to keep.
Sega's arcade games Virtua Fighter and Virtua Fighter 2 used motion capture to animate their 3D fighters. Soon many studios built their own capture stages for games.
Why it mattered. Games became one of the biggest users of mocap, and still are.
Toon Boom grew into the maker of Harmony, software for drawing, rigging and compositing 2D animation. Its tools won Primetime Engineering Emmy Awards in 2005 and 2012.
Why it mattered. Much of the world’s TV animation, including many Indian series, is now made in software like this.
India passed the Pre-Natal Diagnostic Techniques Act, later renamed the PCPNDT Act. It bans using scans or tests to find out or choose the sex of a baby before birth.
Why it mattered. It protects girls, because the sperm, not anyone's choice, decides a baby's sex.
Jeffrey Friedman and teamRockefeller University, New York, USA
Scientists found the gene that was broken in a strain of very fat mice. It made a hormone, called leptin, that fat cells release into the blood. Leptin tells the brain how much energy the body has stored.
Why it mattered. It showed that body fat is not just storage but a hormone-making gland.
World Health Organization study groupGeneva, Switzerland
Osteoporosis means bones so thin they break easily. A WHO study group defined it in older women as a DXA T-score of minus 2.5 or lower. That is, bone density 2.5 standard deviations or more below a healthy young adult's.
Why it mattered. One shared number let doctors everywhere diagnose and track weak bones before they break.
Lawrence Armstrong and colleaguesUniversity of Connecticut, USA
Armstrong's team showed that an 8-shade chart of urine colour tracks how concentrated it is, well enough to guide how much athletes drink. Looking at urine came back, this time with evidence.
Why it mattered. It gave everyone a simple check on hydration.
Environment Canada scientists; WHO and WMOToronto, Canada; Geneva, Switzerland
Canadian scientists created the UV index, and Canada began forecasting it with the weather on 27 May 1992. In 1994 the World Health Organization and World Meteorological Organization agreed one global version. In 2002 they published a guide with its colour scale and advice on protecting skin.
Why it mattered. It told everyone, every day, how quickly sunlight could burn their skin.
The Act set rules for organ donation, recognised brain death so that organs could be donated after death, and banned buying and selling organs. It was amended in 2011 and extended to tissues.
Why it mattered. It is the legal backbone of organ donation in India.
US National Institutes of Health consensus panelBethesda, Maryland
A US National Institutes of Health panel recommended that ulcer patients infected with H. pylori be treated with antibiotics. The same year the WHO’s cancer agency classified the germ as a cause of stomach cancer.
Why it mattered. Ulcers went from a lifelong illness to one that antibiotics can usually cure.
Linda Bartoshuk and colleaguesYale University, USA
Bartoshuk's team found that people fall into three groups for the bitter chemical PROP: non-tasters, medium tasters and "supertasters", who find it intensely bitter and tend to have more fungiform papillae. In their samples, about a quarter of people were supertasters.
Why it mattered. It showed that people really do live in different taste worlds.
A team led by P. Venugopal gave Devi Ram a new heart from a brain-dead donor. Earlier attempts in Bombay in 1968, led by P. K. Sen, had not survived the day. Devi Ram lived for many years afterwards.
Why it mattered. It opened the way for heart transplants across India.
Vishwa Mohan Bhatt from Jaipur plays the Mohan veena, a slide guitar he rebuilt with extra drone and sympathetic strings. He and the American guitarist Ry Cooder met half an hour before recording A Meeting by the River in one evening. The album won the Grammy for Best World Music Album at the 1994 awards.
Why it mattered. A guitar reshaped in India won one of music’s biggest prizes.
The Splendor, a 97 cc four-stroke commuter based on Honda's Cub engine, became India's best-selling motorcycle. By 2009 about a million a year were being sold. Hero took over the Splendor when the partners split in 2011–2012.
Why it mattered. It is the model of the Indian commuter: light, frugal and nearly unbreakable.
India created a Department of Indian Systems of Medicine and Homoeopathy, renamed AYUSH in 2003: Ayurveda, Yoga and Naturopathy, Unani, Siddha and Homoeopathy.
Why it mattered. Siddha became part of a national framework with its own budget.
India created a Department of Indian Systems of Medicine and Homoeopathy in 1995. In 2003 it was renamed AYUSH, for Ayurveda, Yoga and Naturopathy, Unani, Siddha and Homoeopathy.
Why it mattered. Traditional systems got a dedicated place in national health policy.
India's first licensed paging service started in 1995, and circle licences for the rest of the country followed. Motorola was reported to supply about 80% of the pagers.
Why it mattered. For a few years, a pager was India's most affordable mobile connection.
West Bengal's chief minister made India's first mobile phone call. Early tariffs were about ₹16.80 a minute at peak, and incoming calls were charged too.
Why it mattered. Mobiles were pagers' future rivals, but at first they were far too costly for most.
Jyoti Basu and Sukh RamKolkata and New Delhi, India
West Bengal's Chief Minister Jyoti Basu, at Writers' Building in Kolkata, called Union Telecom Minister Sukh Ram in Delhi on a Nokia handset, over the Modi Telstra network. Calls were costly, and for years even receiving one was charged.
Why it mattered. It began the story of the world's second-largest mobile market.
VocalTec released InternetPhone, one of the first programs to carry voice calls over the internet (VoIP). Services like Skype (2003) and today's fibre home phones grew from the same idea.
Why it mattered. Your voice became data, sharing the same network as web pages and videos.
David Fincher and Darius Khondji (Seven); Steven Spielberg and Janusz Kamiński (Saving Private Ryan)USA
Some release prints of Seven were made with Deluxe's CCE, a process that leaves silver in the print for deep blacks and dull colours. For Saving Private Ryan, Technicolor's ENR process drained most of the colour to look like 1940s newsreels. Both are bleach-bypass-style looks.
Why it mattered. These films made the desaturated war-and-crime look famous, and digital graders copy it with a few sliders.
Murch's short book on editing asks why cuts work at all, and sets out his Rule of Six: emotion 51%, story 23%, rhythm 10%, eye-trace 7%, the screen's 2D plane 5% and 3D space 4%.
Why it mattered. It is still one of the most read books on editing.
Toy Story was the first feature film made entirely with computer animation. It is animation, not visual effects, but it used the same tools: 3D models, lights and rendering. See CGIClear for how that works.
Why it mattered. It showed audiences would watch computer images for a whole film, and pushed the tools forward fast.
Toy Story was the first entirely computer-animated feature film. Its 114,240 frames took about 800,000 machine hours, on a farm of 117 Sun SPARCstation 20 computers running day and night. Pixar could finish less than 30 seconds of film a day.
Why it mattered. It showed that a whole feature could be rendered, if you had enough computers and patience.
John Lasseter, Pixar, with DisneyPoint Richmond, California
Toy Story was the first feature film made entirely by computer: 114,240 frames, rendered in about 800,000 machine-hours. The crew grew from 24 to 110 people, with 27 animators. Woody alone had 723 animation controls.
Why it mattered. It launched a new kind of film, and CG soon became the main way animated features are made.
Lucasfilm hired Doug Chiang, born in Taipei, to lead its art department. As design director he shaped the look of the Star Wars prequels from 1999. Years later he said he designs in the iPad app Procreate.
Why it mattered. Big films began to have whole teams of concept artists led by one design director.
Government of India, WHO, UNICEF, Rotary and millions of volunteersAll of India
India held its first national polio immunisation day, giving oral polio drops to every child under five on the same day, at booths, bus stands, railway stations and homes. The drives were repeated for years.
Why it mattered. Reaching every child at once cut off the virus’s chances to spread: herd immunity in action.
In the mid-1990s Sumeet could make 100,000 mixies a month, and about 30 of every 100 mixers sold in India were Sumeets. Then family disputes over the trademark went to the courts, and new competitors arrived after India opened its economy. The brand faded, though the family later tried to revive it.
Why it mattered. The name that invented the Indian mixie lost the market it created.
The Global Positioning System reached full operation in 1995, and in May 2000 its deliberate degradation for civilian users was switched off. Receivers work out speed from the Doppler shift of satellite signals, which is how phones and sat-navs know yours to a fraction of a km/h.
Why it mattered. Anyone can now measure velocity, with direction, anywhere on Earth.
A European directive required household washing machines to carry an energy label, showing how much electricity and water they use. Shoppers could now compare machines, with A as the best grade.
Why it mattered. Labels pushed makers to build machines that heat less water and use less power.
Bah Abba put a small clay pot inside a bigger one and filled the gap with wet sand. As water evaporates from the outer pot it takes heat with it, keeping vegetables inside cool and fresh for days without electricity. It uses the same trick as the clay matka in Indian homes, and it won him a Rolex Award for Enterprise.
Why it mattered. It shows that evaporation, the same cooling that makes sweat work, can help farmers where there is no power.
Eric Cornell and Carl WiemanJILA, Boulder, Colorado
Cornell and Wieman cooled a cloud of rubidium atoms to about 170 billionths of a degree above absolute zero. The atoms merged into one quantum blob, a Bose–Einstein condensate. It had been predicted 70 years earlier by Satyendra Nath Bose in India and Albert Einstein. Wolfgang Ketterle made one soon after, and all three shared the 2001 Nobel Prize in Physics.
Why it mattered. It showed how close to absolute zero we can get, while never quite reaching it.
Barely a year after launch, India had about 200,000 pager subscribers. More than 95% of pagers sold were alphanumeric, against under 20% in richer markets, and most users were individuals rather than companies.
Why it mattered. It showed how badly Indians needed a way to be reached when landlines took months to install.
In Japan, more than 10 million Pocket Bells were in use at the peak, many carried by teenagers, who spelled out messages in number puns such as 14106 for 'aishiteru' (I love you).
Why it mattered. Pager codes were an early form of text-speak.
The Spirit DataCine used a line of sensors instead of a flying spot to read film. It could send pictures out as data files as well as video. It soon became the scanner used for the first digital intermediates.
Why it mattered. Good scans made it possible to grade a whole feature film on a computer.
FutureWave Software, then MacromediaSan Diego and San Francisco, California
FutureSplash Animator let anyone key vector shapes and let the computer tween them. Macromedia bought it and named it Flash; Adobe renamed it Animate in 2016.
Why it mattered. Cheap cut-out and tweened animation spread from the web to television.
In the case Common Cause v. Union of India, the Supreme Court ordered an end to professional (paid) blood donation, licensing of blood banks, and a National Blood Transfusion Council. The ban on paid donors took effect on 1 January 1998, and a National Blood Policy followed in 2002.
Why it mattered. It pushed India towards safer, voluntary donation.
Dr V. Mohan, son of Prof. M. Viswanathan, and his wife Dr Rema Mohan, an eye specialist, founded the Madras Diabetes Research Foundation. It went on to run major studies of diabetes in India, including the national ICMR-INDIAB survey.
Why it mattered. It built the research base that finally measured diabetes across all of India.
Widex launched the Senso, the first commercially successful fully digital hearing aid, and Oticon's DigiFocus followed almost at once. A tiny computer could now shape the sound for each ear and cut background noise.
Why it mattered. Almost every hearing aid sold today is digital.
V. S. Ramachandran and Diane Rogers-RamachandranSan Diego, USA
Indian-born neuroscientist V. S. Ramachandran used a simple box with a mirror to let people see a reflection of their missing arm moving. For some, feelings in the phantom limb changed, and some felt it move.
Why it mattered. It became a famous demonstration that the brain’s body map can change: neuroplasticity.
Steinberg's Virtual Studio Technology, or VST, let audio effects run as plug-ins inside music software on an ordinary computer. In 1999 an update let plug-ins be instruments too, so a whole synthesizer could live on a laptop. VST became a standard used across the music industry.
Why it mattered. Software made synthesizers cheap enough for anyone with a computer.
US Department of Energy and EPAWashington, DC, USA
Dishwashers became an ENERGY STAR product category, alongside fridges and room air conditioners. Models that use much less energy than the rules require can carry the blue star.
Why it mattered. Shoppers could now spot efficient machines at a glance.
Sepp Hochreiter and Jürgen SchmidhuberMunich, Germany
The long short-term memory (LSTM) network added gates that let a network keep information over many steps. Two decades later, LSTMs powered speech recognition and translation on phones.
Why it mattered. It let networks read sequences, the job transformers later took over.
Sepp Hochreiter and Jürgen SchmidhuberMunich, Germany, and Lugano, Switzerland
Sepp Hochreiter and Jürgen Schmidhuber designed the LSTM, a network with memory cells and gates that decide what to keep and what to forget. It could learn from long sequences, like sentences or speech.
Why it mattered. LSTMs later powered speech recognition and translation on phones for years.
PVR turned the old Anupam cinema in Saket into a four-screen multiplex, widely called India's first. It offered several films at once, comfy seats and better sound and projection. Multiplexes then spread across Indian cities in the 2000s.
Why it mattered. Many screens in one building changed how India went to the movies, and slowly squeezed the old single-screen halls.
Geri's Game, a short about an old man playing chess against himself, used Catmull–Clark subdivision surfaces for Geri's skin and clothes, instead of stitched patches that could crack at the seams. It won the Oscar for Best Animated Short.
Why it mattered. Subdivision became the standard way to build characters.
Government of India, with the World Health OrganizationIndia
Many patients stopped their TB pills too early, and the germ came back stronger. India's Revised National TB Control Programme, tested from 1993 and launched nationally in 1997, used the WHO DOTS plan: a health worker watches the patient take each dose. By 2006 it covered the whole country, and in 2020 it was renamed the National TB Elimination Programme.
Why it mattered. Free tests and watched treatment became the backbone of TB care in India.
David Julius and teamSan Francisco, California, USA
David Julius and his team used capsaicin, the chemical that makes chillies hot, to find a sensor on nerve endings in the skin that also fires in painful heat. It is now called TRPV1. In 2002 his team and Ardem Patapoutian's found TRPM8, a sensor set off by cold and by menthol.
Why it mattered. It explained, molecule by molecule, how skin feels heat and cold.
David Julius and colleaguesUniversity of California, San Francisco, USA
Julius's team searched through thousands of genes for one that made cells respond to capsaicin. They found TRPV1, a channel that also opens at painful heat above about 43 °C.
Why it mattered. It explained why chilli feels hot, and opened the science of how we sense temperature.
NASA's Neutral Buoyancy Laboratory, 62 m long, 31 m wide and 12 m deep, holding 23.5 million litres, saw its first suited dives in October 1996 and was dedicated in 1997. Divers trim each suited astronaut with weights and floats until they neither rise nor sink.
Why it mattered. It is the closest thing on Earth to rehearsing a spacewalk.
Engineers built flat detectors from thin layers of amorphous silicon or selenium covered in millions of tiny pixels. The first flat-panel systems appeared around 1995 and spread in the late 1990s. The picture appears on a screen within seconds, with no cassette to carry and no film to develop.
Why it mattered. Most X-ray rooms today use detectors like these.
Fujitsu began mass-producing 42-inch colour plasma panels in October 1996. In 1997 the first plasma TVs went on sale, only about 75 mm thick. They cost as much as a car: about US$15,000 to US$20,000.
Why it mattered. People saw for the first time that a TV could hang on a wall like a painting.
A European directive required new dishwashers to carry a label rating their energy use from A to G, with water use and noise also shown. In 1990 an average new dishwasher sold in the EU used about 30 litres of water per cycle.
Why it mattered. Labels pushed makers to compete on saving energy and water, not just on price.
Clothes washers joined the US ENERGY STAR label in 1997, the same year Maytag launched its Neptune front-loader. The programme says an ENERGY STAR washer today uses about 70% less energy and 75% less water than a standard washer from 20 years earlier.
Why it mattered. Most of a washer's energy goes into heating water, so using less water saves power too.
Akshaya Padhi, K. S. Nanjundaswamy and John GoodenoughUniversity of Texas at Austin, USA
In Goodenough's lab, the graduate student Akshaya Padhi and his colleagues found that lithium iron phosphate could serve as a cathode. They published it in 1997. Iron is cheap and plentiful, and the material stays stable even when it gets hot.
Why it mattered. LFP batteries last thousands of cycles and are safer, so they now fill most home and grid storage.
Toyota put the Prius on sale in Japan, with the tagline ‘Just in time for the 21st century’. It paired a petrol engine with an electric motor and a battery that recharged as the car slowed. It went on sale worldwide in 2000.
Why it mattered. It was the world's first mass-produced hybrid car and brought electric drive back into ordinary cars.
Yann LeCun, Léon Bottou, Yoshua Bengio and Patrick HaffnerAT&T Labs, United States
A long paper described LeNet-5 and a system that read the amounts on handwritten bank cheques. NCR put such readers to work from the mid-1990s, and by around 2000 they were reported to read roughly 10% of cheques in the US.
Why it mattered. It was one of the first times image recognition did everyday work at large scale.
Yann LeCun, Léon Bottou, Yoshua Bengio and Patrick HaffnerAT&T Bell Labs and NCR, United States
Convolutional networks for reading handwritten digits were built into cheque-reading machines. By the late 1990s such systems read several million cheques a day, according to the team's 1998 paper.
Why it mattered. A trained network answering questions at industrial scale, long before chatbots.
Yann LeCun, Léon Bottou, Yoshua Bengio and Patrick HaffnerAT&T Labs, United States
A long paper described LeNet-5, a seven-layer convolutional network with about 60,000 weights, and a system for reading handwritten bank cheques. By around 2000, systems like it were reported to read roughly 10 percent or more of cheques in the United States.
Why it mattered. It was one of the first neural networks doing everyday work at a large scale.
Subscribers in India's 27 licensed cities reached about 8.3 lakh, and fell to about 6.7 lakh a year later. Some later accounts put the peak nearer 20 lakh. A tribunal later dated the industry's decline from 1997–98.
Why it mattered. The boom was already turning as mobile phones got cheaper.
ITU-T approved T.38 for real-time fax over IP networks. Gateways turn the fax sound into data and send it in packets with copies of earlier ones, so a lost packet doesn't ruin the page. T.37, for sending fax as email, came the same year.
Why it mattered. It let fax keep working as telephone networks moved onto the internet.
In Pleasantville, a black-and-white TV town slowly turns to colour. The film was shot in colour, and about 163,000 frames were scanned so artists could drain colour from some parts of the frame and keep it in others. It was the first new feature with most of its footage processed digitally.
Why it mattered. Choosing colour for just one part of a frame is what secondary grading does.
Epic Games released the video game Unreal, running on an engine Sweeney had begun building in 1995. Other studios licensed the Unreal Engine for their own games.
Why it mattered. Twenty years later the same family of software would draw the worlds on LED walls.
International Telecommunication Union (ITU)Geneva, Switzerland
Recommendation ITU-R BT.1359 set out how far sound and picture may drift. Viewers begin to notice when sound is about 45 ms early or 125 ms late, and find it unacceptable beyond about 90 ms early or 185 ms late.
Why it mattered. It gave engineers a clear target for keeping lips and words together.
The anatomist Michael Gershon, who studied serotonin in the gut, wrote a popular book, The Second Brain, about the enteric nervous system. Its hundreds of millions of neurons can run the gut on their own.
Why it mattered. It brought the gut’s own nervous system and the gut–brain axis to a wide public.
Surgeons at Indraprastha Apollo HospitalNew Delhi, India
Sanjay Kandasamy, a 20-month-old boy from Tamil Nadu with biliary atresia, received part of his father's liver. He became India's first successful liver transplant patient. He grew up to become a doctor himself.
Why it mattered. It opened the way for India to become one of the busiest countries in the world for living-donor liver transplants.
The first multi-slice scanners had four rows of detectors and turned in half a second, collecting four slices per turn. That was about eight times the performance of one-second, single-slice scanning.
Why it mattered. More rows meant thinner slices, faster scans and the first good 3D pictures.
LG introduced what it calls the world's first clutch-less drum washing machine built with a direct drive motor. The motor sits right on the back of the drum, with no belt in between, and electronics control its speed for washing and spinning.
Why it mattered. Direct drive made front-loaders quieter and more efficient, and it is now common around the world.
Sachdev had run a cable TV equipment business since the late 1980s. In 1998, seeing how often the power went out, he turned Su-Kam to power backup. Su-Kam made inverters with plastic bodies instead of metal ones and went on to export to more than 90 countries.
Why it mattered. Home inverters became as ordinary in Indian homes as the fan and the fridge.
Galanz, a company that began in 1978 making other goods, started making microwave ovens in 1992. By 1998 it was the biggest microwave maker in the world, with about 40% of the global market. By 2019 it was making about half of the world's microwaves.
Why it mattered. Huge factories in China made microwave ovens cheap enough for families around the world.
David LoweUniversity of British Columbia, Vancouver, Canada
David Lowe's SIFT method found distinctive points in a picture and described each so it could be matched in another photo, even after turning, zooming or a change of light.
Why it mattered. For a decade, hand-made features like SIFT powered panorama stitching, object recognition and robot navigation.
NVIDIA announced the GeForce 256 and marketed it as the world's first GPU, a chip that did the maths for 3D graphics itself instead of leaving it to the main processor. It had about 17 million transistors.
Why it mattered. GPUs do thousands of small sums at once, which later made them perfect for AI.
Research In Motion (Mike Lazaridis)Waterloo, Canada
RIM launched the BlackBerry 850, a two-way pager with a tiny keyboard that pushed email to you. Phone models followed from 2002 and became the favourite of business people and politicians.
Why it mattered. Always-on email made the phone a work tool, and "CrackBerry" a word.
DoCoMo's i-mode service put simple web pages, email and ringtone downloads on ordinary phones. Tens of millions of Japanese signed up within a few years.
Why it mattered. It proved people would use the internet on a phone.
Lucasfilm, Texas Instruments and Hughes-JVCLos Angeles area and New Jersey
Star Wars: Episode I was shown to paying audiences on four screens without any film. Two used Texas Instruments' DLP mirror chip, and two used a rival projector from Hughes-JVC. It is widely seen as the start of digital cinema.
Why it mattered. It proved a chip could match film on a real cinema screen, and DLP went on to power most digital cinemas.
John Gaeta and team, for The MatrixSydney, Australia
For bullet time, about 120 still cameras stood in a curve around the actor, plus two film cameras. They fired one after another, so the camera seems to fly around a frozen moment. Computers filled the gaps between cameras and added the background.
Why it mattered. It mixed a real camera rig with computer work so well that the effect was copied in films, ads and games for years.
Nvidia's GeForce 256 put the maths for moving and lighting triangles onto the graphics chip itself. Nvidia marketed it as the world's first GPU. It rasterised rather than ray traced, but it made real-time 3D fast and cheap.
Why it mattered. Graphics chips grew into the engines that now ray trace in real time.
Pixologic (Ofer Alon and Jack Rimokh)SIGGRAPH, USA
ZBrush was shown at the SIGGRAPH conference in 1999. It lets artists push and pull digital clay with brushes, with millions of tiny faces. Studios like ILM and Wētā FX use it to design creatures and props.
Why it mattered. Designers could turn a drawing into a model you can spin and see from every side.
David Dozoretz, for LucasfilmSkywalker Ranch, California, USA
After David Dozoretz made digital animatics for Mission: Impossible, Lucasfilm hired him to plan the pod race in Star Wars: Episode I, The Phantom Menace. His team made an average of four to six animatics for every effects shot. Directors could now watch a rough 3D version of a sequence before building anything.
Why it mattered. Previs became a normal step in making big films, not an experiment.
Texas Instruments; Lucasfilm; Sony; Digital Cinema InitiativesUnited States
In 1999 a few cinemas showed a feature from digital projectors. Star Wars: Episode II (2002) was one of the first major films shot entirely on digital video, and the big studios agreed a digital-cinema standard in 2005. Within about 15 years most of the world's screens had gone digital.
Why it mattered. Cameras now record to cards and films arrive at cinemas as files, not heavy reels.
Masayasu Kojima, Kenji Kangawa and colleaguesOsaka
Kojima and his team discovered ghrelin, a hormone made mainly in the stomach. Later studies showed its level rises before meals and falls after eating, so it became known as the hunger hormone.
Why it mattered. It showed the stomach helps tell the brain when to eat.
Talvin Singh is a British tabla player and producer from London's Asian Underground scene. His debut album OK mixed tabla with electronic drum and bass, recorded in London, India and Okinawa. It won the 1999 Mercury Prize for the best British album of the year.
Why it mattered. It showed the tabla sounding perfectly at home in electronic dance music.
Mahesh Gupta, an engineer who studied at IIT Kanpur, started KENT RO Systems after his own children fell ill from contaminated water, according to the company. KENT sold home purifiers that used reverse osmosis, a technology then mostly found in factories and plants.
Why it mattered. Home RO purifiers spread fast in Indian cities where groundwater is hard or salty.
Joel and Ethan Coen, Roger Deakins and CinesiteLos Angeles, USA
O Brother, Where Art Thou? was shot in lush green Mississippi, but the story needed a dry, dusty, golden look. Every frame was scanned, the greens were pushed towards yellow digitally, and the result was printed back to film. It is widely cited as the first Hollywood feature to go through a full digital intermediate.
Why it mattered. From here on, a film's colour could be reshaped as freely as a photo.
Pentafour Software (later Pentamedia Graphics)Chennai (then Madras), India, and Los Angeles, USA
Sinbad: Beyond the Veil of Mists was the first feature-length computer-animated film made with motion capture. Actors were captured in Los Angeles in 1997, and a couple of hundred animators in Madras built the film.
Why it mattered. An Indian studio led the first full-length mocap film, years before Hollywood's big ones.
Alan Lee, John Howe and Wētā WorkshopWellington, New Zealand
Book illustrators Alan Lee and John Howe were the lead concept artists for Peter Jackson's Lord of the Rings films. Set builders closely followed some of Lee's drawings. Lee shared the 2004 Oscar for art direction.
Why it mattered. Concept art connected a famous book's world to the sets, props and effects built for the screen.
Nina Jablonski and George ChaplinSan Francisco, California, USA
Anthropologist Nina Jablonski and geographer George Chaplin compared skin colour around the world with how much UV light people's ancestors lived under. Where UV is strong, dark skin protects folate, a vitamin needed for healthy babies. Where UV is weak, lighter skin lets in enough to make vitamin D.
Why it mattered. It explained human skin colour as a balance struck by evolution, not a ranking.
Gavriel Iddan, Paul Swain and Given ImagingYokneam, Israel, and London, England
Engineers at the Israeli company Given Imaging, working with doctors including Paul Swain in London, built a camera the size of a large pill. It takes photos as the gut squeezes it along and sends them by radio to a recorder. Their paper appeared in Nature in 2000, and the US cleared it for use in 2001.
Why it mattered. For the first time doctors could see the whole small intestine without surgery.
Several teams, including Zuker and Ryba, and Linda BuckUSA
Three papers described the T2Rs, a family of about 25 bitter receptors in humans. Many bitter cells carry several kinds, so one cell can warn of many different poisons. The same year, a team in Miami proposed a glutamate receptor for umami.
Why it mattered. It showed why bitter is so sensitive: it is a warning system built to catch thousands of chemicals.
The World Heart Federation and the World Health Organization started World Heart Day to tell people how to protect their hearts. Since 2011 it has been held every year on 29 September.
Why it mattered. It marks a shift from only treating heart disease to preventing it everywhere.
Hariprasad Chaurasia, born in Allahabad in 1938, became the best-known bansuri player in the world. He played with musicians such as George Harrison, John McLaughlin and Zakir Hussain. In 2000 India gave him the Padma Vibhushan, its second-highest civilian honour.
Why it mattered. He carried the bamboo flute of Krishna to audiences on every continent.
GE says it launched the first ‘smart’ auto-sensing dishwasher in 1995. In 2000 Bosch added the AquaSensor, which checks how cloudy the wash water is, and won a Bavarian innovation prize for a machine that picks its own programme.
Why it mattered. A machine that measures how dirty the water is can stop as soon as the dishes are clean, saving water and energy.
On opening day, thousands of walkers made London's new footbridge sway sideways by about 70 mm. People fell into step with the sway, which made it worse. It closed after two days and reopened in 2002 with 37 fluid dampers and 52 tuned mass dampers.
Why it mattered. It showed that people can drive resonance too, and changed how footbridges are designed.
Paul Viola and Michael JonesMitsubishi Electric Research Labs and Compaq, Cambridge, United States
Viola and Jones found faces with thousands of simple light-and-dark box features, chosen by a learning method and checked in a fast cascade. It ran at 15 frames a second on a 700 MHz Pentium III.
Why it mattered. It put face-finding boxes in digital cameras, and its sliding-window idea is the one chapter 4 uses.
IBM's POWER4 put two processor cores on a single chip, the first mainstream processor to do so. AMD and Intel brought dual-core chips to ordinary PCs in 2005.
Why it mattered. When clock speeds stopped rising, computers got faster by adding more cores instead.
The film company Adlabs opened India's first IMAX theatre at Wadala in Mumbai. Its giant screen ran 15/70 film on an IMAX projector. Today India has many IMAX screens, most of them digital or laser.
Why it mattered. It brought the world's biggest film format to Indian audiences.
Jean-Pierre Jeunet and cinematographer Bruno DelbonnelParis, France
Amélie used a digital intermediate to give Paris a warm, storybook glow. Its rich greens, reds and golds are one of the best known looks in modern film. Colourists still name it when describing a warm, magical style.
Why it mattered. It showed audiences that a grade could be a film's personality.
Final Fantasy: The Spirits Within aimed for photorealistic human characters, animated with motion capture. It was the first widely released film made this way.
Why it mattered. It showed how hard it is to make digital humans feel alive, even with real motion.
Stephen Regelous and Weta Digital, for The Lord of the RingsWellington, New Zealand
Peter Jackson needed battles with huge armies. Regelous wrote Massive, software where every digital soldier is an agent that senses, decides and fights on its own. It won an Academy science and engineering award in 2004.
Why it mattered. Crowd software like Massive is how films now fill a battlefield without hiring a hundred thousand extras.
Ed Catmull, Loren Carpenter, Rob CookAcademy of Motion Picture Arts and Sciences, Los Angeles, USA
The Academy gave the three an Oscar statuette for advances in film rendering shown in Pixar's RenderMan. It was reported as the first Oscar statuette for a piece of software. RenderMan had by then been used on films such as The Abyss, Jurassic Park and Titanic.
Why it mattered. Hollywood officially recognised that software could be as important as cameras.
Henrik Wann Jensen, Stephen Marschner, Marc Levoy, Pat HanrahanStanford University, USA
Light does not just bounce off skin, milk or marble. It sinks in, scatters and comes out nearby, which makes them glow softly. Jensen, a Danish researcher, and colleagues found a fast way to render this, and three of them won a technical Oscar in 2004.
Why it mattered. Subsurface scattering is why computer faces stopped looking like plastic.
Sulley in Monsters, Inc. had 2,320,413 hairs, too many to animate by hand. Pixar wrote a simulator, Fizt, that moved the fur by physics after the animators finished, on a render farm of about 3,500 processors.
Why it mattered. Simulation became a department of its own in animation studios.
Richard Taylor; Tania Rodger; Wētā WorkshopWellington
For The Lord of the Rings, Wētā Workshop built huge, detailed models of places like Minas Tirith and Helm's Deep, some very large. The team called them bigatures. Computers then added armies and blended the models with live action.
Why it mattered. Real models give light and detail that early digital sets struggled to match.
A group of five Hollywood gaffers and lighting engineers founded Litepanels in 2001 and built a flat 1×1 panel of light-emitting diodes. Unlike hot tungsten lamps, it ran cool and used little power. Litepanels later won Emmy awards for bringing LED lighting to television.
Why it mattered. LEDs began the move away from hot, power-hungry lamps.
Desai was art director on films including Lagaan (2001) and Devdas (2002). He won four National Film Awards for art direction. In 2005 he opened ND Studios near Mumbai.
Why it mattered. Designing a film's world on a grand scale became a celebrated craft in India too.
Greg Nelson, Charles Zuker, Nicholas Ryba and othersUSA
Teams found a third gene, T1R3, and showed that T1R2 + T1R3 together make the sweet receptor (2001), while T1R1 + T1R3 make the umami receptor for glutamate (2002).
Why it mattered. Umami finally had a receptor of its own, and its place as the fifth basic taste was settled.
Japanese researchers and companies launched the first home heat pump water heater using carbon dioxide as its refrigerant. It pulls heat from outdoor air, mostly at night, and stores the hot water in a tank. More than 4.6 million had been shipped by March 2015.
Why it mattered. It showed heat pumps could make very hot water for homes with far less electricity, using a gas that does not harm the ozone layer.
Bajaj launched the Pulsar 150 and 180, sportier commuters with more power. Later versions added twin spark plugs (DTS-i), disc brakes and fuel injection. This box uses the Pulsar 150's numbers.
Why it mattered. It created a new kind of Indian bike: a commuter that also felt fast.
A six-year-old boy having an MRI scan was fatally injured when a steel oxygen cylinder was pulled into the magnet. The American College of Radiology published its first MR safety guidance the next year.
Why it mattered. It is why MRI units now screen everyone and everything that goes near the magnet.
Richard Shelby, David Smith and Sheldon SchultzUniversity of California, San Diego
Following designs by John Pendry of Imperial College, who argued in 2000 that such a material could make a perfect lens, the San Diego team built a prism from tiny copper rings and wires on circuit boards. Microwaves passing through it bent to the negative side, exactly as Veselago had predicted.
Why it mattered. It was the first experiment to show negative refraction, and started the field of metamaterials, including early invisibility cloaks.
Schmidt simulated a shower on his home computer and found that falling spray sets up a sideways vortex whose low-pressure centre pulls the curtain in. It won him an Ig Nobel prize.
Why it mattered. A reminder that everyday 'Bernoulli' puzzles often have more than one cause.
By 2002 India had only about 5 lakh pager users. Mobiles that could send SMS for far less had become the everyday choice, and pagers lost their status appeal.
Why it mattered. Mobile phones did everything a pager did, and could talk back.
Andy Serkis and Weta DigitalWellington, New Zealand
Serkis acted Gollum on set with the other actors, then again in a marker suit on a capture stage. In The Two Towers his body motion streamed live onto the CG Gollum; animators used his face and voice as the guide for Gollum's face.
Why it mattered. It turned mocap into acting. People began to talk about performance capture and the actor behind the creature.
Andy Serkis and Weta Digital, for The Two TowersWellington, New Zealand
Serkis acted Gollum's scenes and his movements were recorded with motion capture. Animators mixed that data with hand animation, then painted Serkis out and put Gollum in. See MocapClear for how motion capture works.
Why it mattered. It made audiences take a digital character seriously as a real performance.
Gollum in The Lord of the Rings: The Two Towers was driven by actor Andy Serkis's performance, captured on set, then finished by animators keyframe by keyframe (see MocapClear).
Why it mattered. It showed a CG character could give a real acting performance.
Ton Roosendaal and the Blender communityAmsterdam, Netherlands
When the company behind Blender went bust, its users raised €100,000 in seven weeks to buy the program and release it under the GNU General Public Licence. Anyone could now download a complete 3D animation studio for free.
Why it mattered. It opened 3D animation to students and small studios everywhere, including across India.
Sony's HDW-F900 CineAlta camera recorded high-definition video at 24 frames a second, just like film. The French film Vidocq (2001) was shot entirely with it, and George Lucas used it for Star Wars: Episode II (2002), the first big Hollywood blockbuster shot fully in digital.
Why it mattered. It proved a digital camera could make a cinema film, and the long switch from film began.
Experts defined chronic kidney disease by filtration rate and kidney damage, and split it into five stages. An international group, KDIGO, later refined them and added protein in the urine.
Why it mattered. Doctors everywhere could now describe and track kidney disease the same way, as in the CKD stages you can explore here.
Government of India, Universal Immunization ProgrammeIndia
India began giving hepatitis B vaccine in its free national immunisation programme in 2002, starting in 14 cities and then 33 districts. It spread to ten states in 2007–2008 and to the whole country by 2011.
Why it mattered. Millions of Indian children now grow up protected from the most common cause of liver cancer.
World Health Organization and UNICEFGeneva, Switzerland, and New York, USA
In 2002 WHO released a new oral rehydration formula with less salt and sugar, which the gut absorbs even better. In 2004 WHO and UNICEF advised giving it together with zinc tablets for 10 to 14 days. Zinc shortens bouts of diarrhoea and makes them milder.
Why it mattered. These small changes mean fewer children need a drip or a hospital bed.
Alain CribierCharles Nicolle University Hospital, Rouen, France
Cribier squeezed an artificial valve onto a balloon, guided it through blood vessels to the heart, and opened it inside a stiff, narrowed aortic valve. The 57-year-old patient was too ill for open surgery. His blood pressure recovered within minutes.
Why it mattered. TAVI now lets many older patients get a new valve through a small cut in the leg.
Margareta Törnqvist and the Swedish Food AgencyStockholm University, Sweden
Swedish scientists studying a sealant leak in a railway tunnel found acrylamide, a chemical that may cause cancer, even in the blood of people who were never near the tunnel. They traced it to food. With the Swedish Food Agency, they announced that frying and baking starchy foods like potatoes forms acrylamide.
Why it mattered. It changed how the world thinks about very brown, crisp food.
Donald Mottram and team, and Richard Stadler and teamBritish universities, and Nestlé Research, Switzerland
Two teams reported in the journal Nature that acrylamide forms during the Maillard reaction. The key ingredient is asparagine, an amino acid found in potatoes and cereals, reacting with sugars at high heat. The browner the food, the more acrylamide it tends to hold.
Why it mattered. The same reaction that makes chips tasty can also make something harmful, so the colour you stop at matters.
Trials showed that a slightly weaker solution works better: less sodium and glucose, 245 mOsm/L instead of 311. The WHO and UNICEF recommended it worldwide. It cut stool volume by about a quarter and the need for drips by about a third.
Why it mattered. A slightly hypotonic drink lets water into the body more easily, which is osmosis doing its job.
Yoshua Bengio and colleaguesUniversité de Montréal, Canada
Bengio's team trained a neural network to predict the next word, learning a vector for every word along the way. Similar words got similar vectors, so the model could handle sentences it had never seen.
Why it mattered. Next-word prediction plus learned word vectors is the recipe LLMs still follow.
The Nokia 1100, a tough, cheap phone with a torch and a dust-proof keypad, came out in 2003. It sold about 250 million units, among the best-selling electronic gadgets ever, many of them in India.
Why it mattered. Cheap, rugged handsets brought mobile phones to villages and small towns.
Prime Focus began digital work on effects scenes in 2001. In 2003 it graded all of Qayamat, described as the first entirely colour graded film in India. In 2004 it set up its DI suite inside the Adlabs film lab, and went on to grade dozens of Hindi films.
Why it mattered. Digital grading arrived in India only three years after Hollywood's first full DI.
Subrata Sen; Kamal Haasan; Dibakar BanerjeeKolkata, Chennai and Mumbai, India
The Bengali film Nil Nirjane (2003) is often called India's first feature shot on digital video. Mumbai Xpress (2005) is described as the first censored Indian film filmed in digital format, and Love Sex Aur Dhokha (2010) was also billed as a first, shot entirely on small digital cameras. Which one counts depends on how you define 'first'.
Why it mattered. Cheap digital cameras let new filmmakers in India make features without buying film stock.
Rita Colwell and colleagues at icddr,bMatlab, Bangladesh
Rita Colwell, an American microbiologist, knew cholera bacteria cling to tiny water animals. Her team showed village women how to pour pond and river water through an old sari folded several times. In the villages that filtered their water, cholera cases fell by about half.
Why it mattered. Stopping germs before they reach the gut is as important as treating them after.
Paul Lauterbur and Peter MansfieldStockholm, Sweden
The Nobel Prize in Physiology or Medicine went to Lauterbur and Mansfield for their discoveries concerning MRI. Damadian was left out. Supporters of Damadian ran full-page newspaper advertisements arguing that he should have shared it. The prize can go to at most three people, and the committee’s discussions stay sealed for 50 years.
Why it mattered. It recognised imaging with gradients, and left a lasting debate about who deserves credit.
Rainer Stamminger and teamUniversity of Bonn, Germany
Researchers asked 113 people from across Europe to wash 12 place settings by hand. On average they used 103 litres of water and about 2.5 kWh of energy. An efficient dishwasher of the time did the same load with about 15 litres and 1 to 2 kWh, and usually got it cleaner.
Why it mattered. It showed that a modern dishwasher saves water and energy compared with most people at the sink.
Babinsky filmed smoke pulses flowing past a wing in a wind tunnel. The smoke over the top reached the back edge well before the smoke underneath, and never met up again, disproving the popular 'equal transit time' explanation of lift.
Why it mattered. It is the experiment chapter 5's myth-buster recreates.
A study in JAMA found lead, mercury or arsenic in 14 of 70 Ayurvedic products bought in Boston shops. A 2008 follow-up found them in about a fifth of products sold online, and far more often in metal-based formulas.
Why it mattered. It raised worldwide questions about metal-based traditional medicines, including Siddha's.
Tests found potentially harmful lead, mercury or arsenic in 14 of 70 Ayurvedic products from Boston shops. A 2008 study of 193 products sold online found metals in about 1 in 5, and in about 4 in 10 metal-based rasa shastra products.
Why it mattered. It made product safety a global concern.
Robert Zemeckis, Sony Pictures Imageworks and ViconCulver City, California, USA
The Polar Express used 72 cameras around a capture area about 10 feet (3 m) square. Up to four actors were captured together, bodies and faces: each wore about 48 body markers and 152 small face markers.
Why it mattered. It was the first film shot entirely on a motion-capture stage, and showed face capture's promise and problems.
A group of artists who had made previs for Star Wars: Episode III at Lucasfilm set up their own company, The Third Floor. The name comes from the top floor of Skywalker Ranch, where they had worked. It went on to plan scenes for many blockbuster films and series.
Why it mattered. Planning shots in a computer had become a whole industry.
Buck and Axel were awarded the Nobel Prize in Physiology or Medicine “for their discoveries of odorant receptors and the organization of the olfactory system”, including how neurons of one type all wire to the same spots in the olfactory bulb.
Why it mattered. Smell, long the least understood sense, joined the best understood.
Martin Dienwiebel, Joost Frenken and colleaguesLeiden, Netherlands
With a very sensitive friction microscope, the Leiden team dragged a tiny graphite flake over graphite and turned it. Friction was high only when the flake's atoms lined up with those below, every 60°. In between it almost disappeared.
Why it mattered. It proved that friction can nearly vanish when atomic bumps can't lock together.
Announced at RSNA in 2003, the first 64-slice scanners were installed in 2004. With 64 rows of 0.625 mm detectors, a heart could be scanned in about 5 to 8 seconds, making CT pictures of the coronary arteries practical.
Why it mattered. CT angiography of the heart became a routine test.
Doordarshan launched DD Direct Plus, now called DD Free Dish, a satellite service with no monthly fee. Anyone with a small dish and a set-top box could watch. By 2022 it reached over 43 million homes.
Why it mattered. It brought many channels to villages where cable never went.
The analysis compared 110 homeopathy trials with 110 matched trials of ordinary medicine. In the larger, better-run trials, homeopathy's effects were compatible with placebo, while ordinary medicine's were not. Homeopaths criticised how trials were chosen.
Why it mattered. It was one of the most cited studies in the debate about homeopathy.
Navneet Dalal and Bill TriggsINRIA, Grenoble, France
Dalal and Triggs described people by histograms of edge directions (HOG) in small cells, and slid a detector over the picture. It became a standard way to find pedestrians.
Why it mattered. It was among the best hand-made detectors just before learned features took over.
Adrian Bowyer and the RepRap communityUniversity of Bath, England
Bowyer proposed RepRap in 2004, and the project got going at the University of Bath in 2005: an open-source, cheap 3D printer that could print many of its own parts. Its Darwin model of 2008 printed about half of its own plastic parts, and hundreds of people worldwide joined in.
Why it mattered. Open designs made hobby 3D printers cheap, which is why schools and makers now have them.
Digital Cinema Initiatives (DCI)Hollywood, California
In March 2002 seven big Hollywood studios formed Digital Cinema Initiatives to agree on how digital films should be packed, locked and shown. On 20 July 2005 they published version 1.0 of the DCI Specification. It set 2K and 4K pictures, JPEG 2000 compression and encrypted files that only open with a digital key.
Why it mattered. With one standard, any film could play on any approved projector anywhere in the world.
UFO Moviez, founded in Mumbai in 2004, began converting cinemas in 2005 to digital projectors that download films by satellite. Chennai's Qube Cinema launched its own digital cinema system the same year. By March 2008 UFO had digitised more than 1,000 cinemas, many in small towns.
Why it mattered. Cheaper digital copies let small-town halls show new films on the same day as big cities, years before most of the world went digital.
Mangal Pandey: The Rising was one of India's most expensive films of its time. It was released in Hindi and English around the world. Prime Focus used a digital intermediate to keep its period look consistent across all six master negatives.
Why it mattered. Big Indian films began to plan their look for the grading suite from the start.
Digital Cinema Initiatives (seven Hollywood studios)Hollywood, USA
DCI released version 1.0 of its Digital Cinema System Specification. It set how digital films are packaged and projected, including the DCI-P3 range of colours and a white of 48 nits on screen. Cinemas everywhere, including in India, followed these rules.
Why it mattered. Colourists now had one standard cinema picture to grade for.
Andy Serkis and Weta DigitalWellington, New Zealand
For King Kong, Serkis studied gorillas at London Zoo and in Rwanda. He had 135 small markers glued to his face, about two hours of make-up a day, to drive the ape's expressions.
Why it mattered. Face markers mapped a human face onto a very different creature face, a big step in retargeting.
V. G. Samant; Percept Picture Company and SilvertoonsMumbai
Hanuman, a hand-drawn (2D) feature about the monkey god, earned about ₹11.7 crore on a budget of about ₹3.25 crore. It is widely credited with starting the boom in Indian animated films, though it was not made in 3D (see Anim2DClear).
Why it mattered. It proved Indian audiences would pay for animated features.
The DCI specification defined the Digital Cinema Package. Its audio is uncompressed: 24-bit, 48 or 96 kHz, up to 16 channels in one package with the pictures and subtitles.
Why it mattered. Film prints gave way to hard drives, and the soundtrack lost the noise and wear of film.
Qube Cinema and UFO MoviezChennai and Mumbai, India
Instead of shipping heavy film prints, Qube and UFO Moviez sent films digitally, UFO by satellite, to low-cost digital projectors. In 2005 the Abirami complex in Chennai became India's first all-digital cinema. Thousands of small-town screens followed.
Why it mattered. Digital delivery let a film open in many more towns on the same day, without costly prints.
The screenwriter Blake Snyder published Save the Cat!, which splits a film into 15 beats, from the Opening Image to the Final Image. The title is his advice to let the audience see the hero do something kind early on. It became one of the most popular books on story structure.
Why it mattered. It gave writers a detailed beat sheet to test a story against, page by page.
Janani Suraksha Yojana, National Rural Health MissionIndia
The Government of India launched Janani Suraksha Yojana (JSY), which gives cash help to poorer mothers who give birth in a hospital or health centre, supported by community health workers called ASHAs.
Why it mattered. Births in health facilities rose steeply, to 88.6% by 2019–21.
Karikó and Weissman found that swapping one building block of mRNA kept it from setting off alarm bells in the immune system. Their work, long ignored, made mRNA vaccines practical. They won the 2023 Nobel Prize.
Why it mattered. It let scientists design a new vaccine in days once a virus’s genes were known.
Marshall and Warren won the Nobel Prize in Physiology or Medicine for discovering Helicobacter pylori and its role in gastritis and ulcers. Marshall had even drunk a culture of the germ in 1984 to prove it could make a healthy stomach ill.
Why it mattered. It honoured an idea most experts had laughed at twenty years earlier.
Marshall and Warren won the Nobel Prize in Physiology or Medicine “for their discovery of the bacterium Helicobacter pylori and its role in gastritis and peptic ulcer disease”.
Why it mattered. It honoured an idea that most experts had laughed at twenty years earlier.
World Health Organization member statesGeneva, Switzerland
The World Health Assembly adopted the Framework Convention on Tobacco Control on 21 May 2003, and it came into force on 27 February 2005. India ratified it in 2004, and in 2003 passed its own tobacco law, COTPA.
Why it mattered. Taxes, warnings and smoke-free places have helped cut tobacco use, including in India.
The SOMATOM Definition carried two X-ray tubes and two detectors on the same ring. At 0.33 s a turn, it could collect a slice of the heart in just 83 milliseconds, and the two tubes could run at different voltages for dual-energy scans.
Why it mattered. It froze the beating heart and made dual-energy CT practical.
NASA Human Research FacilityInternational Space Station
During Expedition 11, the Space Linear Acceleration Mass Measurement Device was installed on the ISS. Springs pull the astronaut's guide arm with a known force, a sensor measures the acceleration, and a laptop works out m = F ÷ a, from 43 to 109 kg, to about 0.2 kg.
Why it mattered. Newton's second law became a bathroom scale for space.
Google Translate launched using statistical machine translation, trained on huge collections of translated documents from the United Nations and the European Parliament. It moved to neural networks in 2016.
Why it mattered. Millions of people began using language models every day without knowing it.
Geoffrey Hinton, Simon Osindero and Yee-Whye TehUniversity of Toronto, Canada
Hinton and colleagues showed a way to train a deep network by first teaching it one layer at a time, then fine-tuning the whole thing. They called it a deep belief net.
Why it mattered. It made "deep learning" a respectable phrase again and drew researchers back to many-layer networks.
Marcos Fajardo (Arnold) and Sony Pictures ImageworksMadrid, Spain, and Culver City, USA
Fajardo, from Spain, wrote a renderer that traced random paths of light, as Kajiya had described. Sony Pictures Imageworks used it, named Arnold, on Monster House (2006) and Cloudy with a Chance of Meatballs (2009). In 2017 the Academy honoured Arnold, crediting it with leading a wide move to fully ray-traced film rendering.
Why it mattered. It proved brute-force path tracing could work for a whole film, and studios soon followed.
An earlier ban on selling non-iodised salt for eating had been lifted in 2000. In 2005 the government brought it back under food law, and it took effect in May 2006. Salt for people to eat had to have iodine added.
Why it mattered. A national rule made sure iodine reached families without them having to choose it.
Colin Palmer, Irwin McLean and colleaguesDundee, Scotland
Researchers found that many people with eczema carry faulty copies of the gene for filaggrin, a protein that helps build the skin's tough outer barrier. With a weaker barrier, water escapes and irritants and germs get in more easily.
Why it mattered. It showed that the outer layer of skin is a working barrier, and that when it fails, disease can follow.
The US approved the Dexcom STS, a small sensor under the skin that showed glucose every few minutes in real time. Earlier systems had only recorded data for a doctor to read later.
Why it mattered. Continuous glucose monitors changed daily life for many people with diabetes.
Mehmood Dhaulpuri, Appa Jalgaonkar and Tulsidas BorkarNew Delhi, India
Mehmood Dhaulpuri accompanied great singers such as Bhimsen Joshi, Kishori Amonkar and Girija Devi. In 2006 he received the Padma Shri, and he is widely described as the first harmonium player to get it. Appa Jalgaonkar had won a Sangeet Natak Akademi Award in 2000, and Tulsidas Borkar received the Padma Shri in 2016.
Why it mattered. India's government was now honouring the instrument its radio had once banned.
Doctor and musicologist Vidyadhar Oke built a harmonium with small knobs under the keys that let each note be nudged to the right shruti. Singer Rahul Deshpande used it on stage at the Sawai Gandharva festival in Pune, in December 2006 or 2007 depending on the source. Oke later received an Indian patent for it.
Why it mattered. It tries to fix the very tuning problem that got the harmonium banned.
Under the Energy Conservation Act 2001, the BEE launched its star labels: one to five stars showing how many units a year an appliance needs. From 7 January 2010 labels became mandatory for frost-free fridges, room ACs, tube lights and distribution transformers.
Why it mattered. Families could compare the energy bill before buying, not after.
The French company Groupe SEB launched the Tefal ActiFry. A paddle slowly stirs the chips while hot air blows over them, and you add just one spoonful of oil. It is often called the first hot-air fryer sold to the public.
Why it mattered. It proved that people would buy a fryer that used air instead of a bath of oil.
Van der Weij, a Dutch inventor, was unhappy with a fat-free fryer he had bought, so he set out to crisp chips with hot air alone. His first prototype, made of wood and aluminium with a chicken-wire basket, was almost as big as a dog kennel. He patented his rapid air idea, with a shaped guide at the bottom that turns the air up through the food.
Why it mattered. He found a way to make fast-moving hot air do the job of hot oil in a small box.
IS 4250 first covered mixers of up to 600 watts. Amendment No. 9, in February 2006, raised the limit to 750 watts. Today most Indian mixer grinders sit between 500 and 750 watts.
Why it mattered. More power helps the motor keep spinning through hard spices and thick batter without slowing down.
Tamil Nadu applied in 2005, and the ‘Coimbatore Wet Grinder’ became a registered geographical indication from March 2006, like Darjeeling tea. In 2015 more than 700 makers in the area turned out about 75,000 wet grinders a month.
Why it mattered. The city where Sabapathy built the first wet grinder became famous for them.
A long-lost handwritten copy of Hooke's minutes of Royal Society meetings was found in a cupboard in a house in Hampshire. Many historians read it as tipping the old balance-spring dispute towards Hooke.
Why it mattered. Three centuries on, the argument over who invented the spring-regulated watch was still alive.
Pearl River and other Chinese makersGuangzhou, China
Pearl River Piano was founded in Guangzhou in 1956 and can now make more than 100,000 pianos a year, in the world's largest piano factory. By 2006 China was the largest piano-producing country, making more than 370,000 pianos.
Why it mattered. Most new acoustic pianos in the world are now built in China.
Pilot's FriXion pens use thermosensitive ink that turns clear when warmed. Rubbing with the pen's rubber tip makes enough heat from friction to erase it.
Why it mattered. A new trick for an old tool, from chemistry rather than mechanics.
Apple, presented by Steve JobsSan Francisco, California
Apple showed the iPhone, a phone with a touchscreen, a web browser and a full operating system. The first Android phone followed in 2008. Smartphones soon became the most common computers on Earth.
Why it mattered. For billions of people, their first computer is a phone.
Apple's iPhone, announced on 9 January and sold from 29 June, replaced the keypad with a large multi-touch screen and a full web browser. Its App Store followed in 2008.
Why it mattered. It set the shape of the modern smartphone: one big screen, fingers, apps.
Jannard, who had founded Oakley sunglasses, announced the RED One in 2006 and began shipping it in August 2007. It recorded 4K images as compressed raw files for a fraction of the price of older digital cinema cameras. Steven Soderbergh used prototypes to shoot Che (2008).
Why it mattered. Affordable 4K raw pushed the old camera makers to go digital fast.
Human Microbiome Project Consortium, NIHAbout 80 institutions, mainly in the USA
The US National Institutes of Health launched the Human Microbiome Project in 2007. Scientists sampled 242 healthy adults at many body sites and read the genes of their microbes. In 2012 they published a map of the normal microbes of healthy people, with the gut among the richest places.
Why it mattered. It turned the gut’s bacteria from a curiosity into a major field of science.
Paul Bosland, Chile Pepper InstituteNew Mexico State University, USA, with seeds from north-east India
Guinness World Records certified the bhut jolokia, the "ghost pepper" grown in Assam and nearby states, as the world's hottest chilli, after lab tests measured 1,001,304 Scoville heat units.
Why it mattered. It was the first chilli certified above a million SHU, nearly double the previous record holder.
The National Programme for Prevention and Control of Deafness began as a pilot in 25 districts of 10 states and one union territory. It aims to find and treat ear problems early and has since spread to hundreds of districts.
Why it mattered. It brought ear and hearing care into India's public health system.
Government of Karnataka and BESCOMBengaluru, Karnataka, India
From 2007, Karnataka required solar water heaters on new homes of 600 square feet or more built on plots of at least 1,200 square feet. From April 2009, Bengaluru's power company BESCOM refused regular connections to homes without one.
Why it mattered. Strict checking turned Bengaluru into a model city for solar water heating.
Toshiba's Aquilion ONE had 320 rows of detectors covering 16 cm, enough to image a whole heart or brain in a single rotation without moving the table. It began shipping in 2008.
Why it mattered. Wide detectors let CT watch blood flow through a whole organ over time.
For the first time, more LCD TVs were sold around the world than CRT TVs: about 47% against 46% in the last three months of 2007. In richer countries the switch had come a few years earlier. Within a decade, big factories had stopped making picture tubes.
Why it mattered. The glass tube that had defined television for 70 years began to disappear.
Sony’s XEL-1 had an 11-inch screen only 3 mm thick and cost 200,000 yen. Because each pixel makes its own light, black parts of the picture could be truly black. It was small, pricey, and more of a preview than a family TV.
Why it mattered. It proved OLED could make a television, not just a tiny phone screen.
The first iPhone used a built-in accelerometer to turn its screen when you turned the phone. Inside, a speck of silicon hangs on springs finer than a hair.
Why it mattered. Billions of people now carry Hooke's law in their pockets.
Jugal Hansraj; Yash Raj Films and Walt Disney Pictures; Tata Elxsi VCLBengaluru and Mumbai
Roadside Romeo, a comedy about a street dog in Mumbai, is widely described as India's first full-length 3D computer-animated film. About 150 artists at Tata Elxsi's Visual Computing Labs in Bengaluru worked on it for two and a half years. It won the National Film Award for Best Animated Film.
Why it mattered. It showed that a full CG feature could be made in India.
Chhota Bheem premiered on Pogo and became one of India’s most popular children’s shows, with films, games and merchandise. Indian channels began to commission their own series instead of only buying foreign ones.
Why it mattered. It showed that Indian studios could create hit characters of their own, not only work for others.
Canon's EOS 5D Mark II was a photo camera that could also record full HD video on a big full-frame sensor. Its shallow focus looked cinematic and it cost very little by film standards. In 2010 a whole episode of the TV drama House was shot on it.
Why it mattered. Students and independent filmmakers everywhere suddenly had a cinematic-looking camera.
Maresh, Gil, Whitman and GreerYale University, USA
Studying human olfactory bulbs, researchers found more than 5,500 glomeruli on average, about 16 for each receptor type, not the 2 per type seen in mice.
Why it mattered. Human smell wiring turned out to differ from the mouse model everyone had assumed.
Iterative reconstruction methods such as GE's ASiR replaced part of filtered back-projection with repeated guess-and-correct steps that model noise. Studies suggested similar image quality at about half the dose. Other makers followed, and today some use deep learning.
Why it mattered. Dose fell a long way while pictures stayed sharp.
BSH (Bosch and Siemens) with the Bavarian Center for Applied Energy ResearchDillingen, Germany
BSH put zeolite, a mineral full of tiny holes, into a dishwasher. Zeolite soaks up water vapour from the air inside and gives off heat as it does, which helps dry the dishes. BSH says this saves up to 20% of the energy per wash.
Why it mattered. It was then the most energy-efficient dishwasher in the world, and it won two German awards in 2009.
Tesla delivered its first Roadster, a sports car powered by 6,831 small lithium-ion cells like those in laptops, with an official range of 244 miles. Only about 2,450 were built. In June 2012 Tesla began delivering the Model S, a family car with software updates sent over the air.
Why it mattered. They showed that an electric car could be fast, go far on a charge and be something people wanted.
At the Auto Expo in New Delhi, Ratan Tata drove the tiny Tata Nano onto the stage. Its price was one lakh rupees, then about US$2,500, so that families of four who rode together on one motorbike could afford a car. Deliveries began in 2009.
Why it mattered. It became a symbol of the push to make cars affordable for hundreds of millions of new drivers in Asia.
Drugs Controller General of India and ICMRNew Delhi
Registering clinical trials in the Clinical Trials Registry–India (CTRI) became mandatory, so trials, including trials of AYUSH medicines, are announced before results are known.
Why it mattered. Registration stops failed trials from quietly disappearing.
Fei-Fei Li, Jia Deng and colleaguesPrinceton University, United States
Fei-Fei Li's team presented ImageNet, millions of photos sorted into thousands of categories, labelled with help from online workers. From 2010 it ran a yearly contest with 1,000 categories.
Why it mattered. It gave learning systems enough varied examples to learn from, and a fair test to compare them.
Rajat Raina, Anand Madhavan and Andrew NgStanford University, United States
The team ran large neural networks on graphics chips (GPUs) meant for video games, and reported training up to about 70 times faster than on a dual-core CPU. A job of weeks became about a day.
Why it mattered. The same parallel multiply-adds later made GPUs the main engine for AI inference too.
Fei-Fei Li, Jia Deng and colleaguesPrinceton University, United States
Fei-Fei Li's team presented ImageNet, a huge collection of photos sorted into thousands of categories, labelled with help from online workers. From 2010 it hosted a yearly contest, the ImageNet Large Scale Visual Recognition Challenge.
Why it mattered. Big, varied data is one of the best cures for overfitting, and ImageNet gave networks enough of it.
TeliaSonera opened the first commercial LTE networks in Stockholm and Oslo, using OFDM and MIMO antennas. At first you needed a USB modem, not a phone.
Why it mattered. LTE made the network carry everything, even voice, as internet packets.
RealD, Dolby and James CameronNorth America, then worldwide
The first RealD 3D cinemas opened in North America in 2005. One digital projector flashes left-eye and right-eye pictures in turn, three times each per frame, and a filter and glasses send each picture to the right eye. By 2009 more than 10,000 screens were 3D-ready, and Avatar made 3D a worldwide hit.
Why it mattered. 3D needed fast, exact digital projectors, so it pushed many cinemas to switch from film.
Blackmagic Design, a company from Australia, bought da Vinci Systems. At the time, Resolve ran on expensive special hardware and had only about 100 users. Blackmagic soon made it run on ordinary Mac and Windows computers.
Why it mattered. It was the first step towards putting a Hollywood grading tool on anyone's laptop.
Avatar was made with a 'virtual camera': James Cameron could see the motion-capture actors as their digital characters in the CG world, in real time, while he framed the shot. He compared it to a big, powerful game engine.
Why it mattered. Directors began to frame shots of virtual worlds as if they were real (see MocapClear).
James Cameron, Lightstorm and Weta DigitalLos Angeles, USA and Wellington, New Zealand
For Avatar, actors wore skull caps with a tiny camera on a boom in front of the face, instead of hundreds of glued markers. Cameron used a virtual camera to see the Na'vi in Pandora live, on a capture stage described as six times larger than any before.
Why it mattered. The head-mounted camera and virtual camera became standard tools of performance capture.
James Cameron and Wētā Digital, for AvatarWellington, New Zealand, and Los Angeles, USA
Most of Pandora, and all of the Na'vi, were made in computers. Actors wore head-mounted cameras and face markers so their expressions could drive the digital characters. Wētā alone made more than 1,800 stereoscopic effects shots.
Why it mattered. It showed that a film could live almost entirely in a digital world and still feel real.
LAIKA's first feature was the first stop-motion feature shot in stereoscopic 3D. Its faces were designed on computers and 3D-printed, about 20,000 of them. 29 animators together made about 90 to 100 seconds of film a week.
Why it mattered. 3D printing made replacement faces precise and very varied.
Resul Pookutty, with Ian Tapp and Richard PrykeLos Angeles, USA
Resul Pookutty, a sound engineer from Kerala who trained at the Film and Television Institute of India in Pune, won the Academy Award for Best Sound Mixing for Slumdog Millionaire, shared with Ian Tapp and Richard Pryke.
Why it mattered. It put Indian film sound engineers on the world stage.
Slumdog Millionaire was filmed in the streets of Mumbai, much of it on the tiny Silicon Imaging SI-2K digital camera, which could be held in the hand and hidden in crowds. Dod Mantle won the Academy Award for Best Cinematography. It was the first film shot mainly in digital to win it.
Why it mattered. It showed the world's top prize for camera work could go to digital.
James Cameron; Weta DigitalCalifornia and Wellington, New Zealand
For Avatar, actors wore suits and head cameras that recorded their bodies and faces, and the director watched a rough computer version of the scene live through a virtual camera.
Why it mattered. Actors' performances could now drive fully digital characters.
Frederico Azevedo, Suzana Herculano-Houzel and colleaguesRio de Janeiro and São Paulo, Brazil
Herculano-Houzel’s team dissolved brains into a soup of cell nuclei and counted them. Four adult male brains held on average about 86 billion neurons and a similar number of other cells, not the 100 billion neurons and ten times more glia often quoted.
Why it mattered. It replaced a guessed number with a measured one.
US National Institutes of Health and university teamsUSA and UK
The NIH launched the Human Connectome Project in 2009 and funded two research groups in 2010. They scanned over a thousand healthy adults to map the brain’s connections, and shared the data freely.
Why it mattered. Open maps of brain wiring now support research worldwide.
In 2009 China sold about 13.6 million vehicles, overtaking the United States as the largest car market in the world. The US had held that title since the days of the Model T. China has stayed number one ever since.
Why it mattered. The centre of the car world began to shift to Asia, and China went on to lead the electric car boom.
Dyson's Air Multiplier hides a small impeller in its base, which pushes air out of a thin slot in a ring. The fast jet drags surrounding air along with it, so much more air moves than passes through the motor. Toshiba had patented a similar bladeless idea in 1981 but never sold it.
Why it mattered. It proved a fan can move a room's air by pulling it along, not just by pushing it with blades.
Ice crystals briefly blocked the Pitot tubes of an Airbus A330 flying from Rio de Janeiro to Paris. With confusing airspeed readings the crew lost control and all 228 people on board died. Investigators found the icing was a contributing factor.
Why it mattered. Airspeed from ½ρv² is so vital that airliners carry several Pitot tubes and heat them.
After long demands from the Siddha community, CCRAS was split and the Central Council for Research in Siddha (CCRS) was set up, headquartered in Chennai, with research units in several states.
Why it mattered. Siddha research now had its own national body.
Researchers at IIT Bombay reported tiny particles of the starting metal in some commercial high-potency metal remedies. The idea has not been independently confirmed as a way remedies act, and it does not cover plant remedies.
Why it mattered. It is one of the Indian research lines homeopaths cite, still debated.
Many 2000s blockbusters pushed skin towards orange and shadows and skies towards teal. The two colours sit on opposite sides of the colour wheel, so faces pop out. In 2010 a much-shared blog post by Todd Miro begged Hollywood to stop overdoing it.
Why it mattered. It made millions of viewers notice colour grading for the first time.
V. Srinivas Mohan and team, for EnthiranChennai, India
Enthiran starred Rajinikanth as a scientist and as Chitti, the robot he builds. His face was 3D scanned, a US studio built animatronic robots, and computer effects filled the action scenes. It was called India's most expensive film at the time.
Why it mattered. It won the National Film Award for special effects and showed Indian films could aim at Hollywood-scale effects.
EBU R 128 told broadcasters to set programmes by measured loudness, −23 LUFS, instead of by their loudest peaks. Streaming services adopted similar targets, such as Netflix's −27 LKFS measured on dialogue.
Why it mattered. It ended the loud-advert problem and gave mixers room for real dynamics.
Chris Corbould; Guy Hendrix Dyas; Christopher NolanCardington, Bedfordshire
For Inception, a 100-foot hotel corridor was built inside an old airship hangar. It hung on eight giant rings and could be turned a full circle by two big electric motors. Actors really fought while the room rolled around them.
Why it mattered. It updated the rotating-room idea from Royal Wedding and 2001 for a modern action film.
Murthy, who shot Pyaasa and Kaagaz Ke Phool for Guru Dutt, was chosen for the Dadasaheb Phalke Award for 2008. The choice was announced in January 2010. It was the first time the award went to a cinematographer.
Why it mattered. India's highest film honour recognised that light and camera are an art in themselves.
ARRI showed the Alexa digital cinema camera in April 2010. Its sensor had a base sensitivity of EI 800, far faster than most film, with a wide range from deep shadow to bright highlight. It quickly became one of the most used cameras in feature films.
Why it mattered. With cameras this sensitive, a single practical lamp or a window can light a whole scene.
ARRI's first big digital hit had a Super 35 size sensor that captured more than 14 stops of light, from deep shadow to bright sky, with a look many compared to film. ALEXA cameras shot five Best Cinematography Oscar winners in a row from 2011 to 2015. Its 2022 successor, the ALEXA 35, claims 17 stops.
Why it mattered. Wide dynamic range and film-like colour convinced even film-loving cinematographers to switch.
Jayaram Chandrashekar, Charles Zuker, Nicholas Ryba and colleaguesUSA
Mice without the sodium channel ENaC in their taste cells lost their liking for low salt. So ENaC is the sensor for pleasant saltiness, while very salty food also triggers bitter and sour cells.
Why it mattered. It explained why a little salt tastes good and a lot tastes bad.
A. O. Smith, Ariston and RacoldBengaluru and Pune, India
In 2010 A. O. Smith, the company behind the glass-lined tank, opened a water heater factory in Bengaluru and later made it much bigger. Italy's Ariston had already bought Racold, then India's largest water heater maker, in the 1990s.
Why it mattered. India had become one of the world's big markets for geysers.
Japan's IKAROS unfolded a 14 m × 14 m sail, thinner than a hair, on its way to Venus. Tracking its orbit, JAXA measured a push of about 1.12 millinewtons from sunlight alone: the first spacecraft to be driven between the planets by light's momentum.
Why it mattered. Light's momentum became a working way to travel through space.
Philips and Fred van der WeijIFA consumer electronics fair, Berlin, Germany
After several more prototypes, van der Weij signed a deal with Philips. Philips showed its Airfryer at the IFA fair in Berlin, promising crispy fries with little or no added oil. It used what Philips called Rapid Air technology: a heater above the basket and a fast fan blowing hot air down and around the food.
Why it mattered. A big global brand turned one inventor's box into a new kind of kitchen appliance.
In May 2006 India's Bureau of Energy Efficiency launched a star label for appliances, from one star to five, and fridge makers could use it if they chose. From 7 January 2010 the label became compulsory for frost-free fridges. It shows how much electricity the fridge uses in a year, and more stars mean less power.
Why it mattered. Shoppers could finally compare running costs, and makers competed to earn more stars.
Godrej designed the ChotuKool with village women: a small, top-opening cool box for rural homes. It uses a solid-state cooling chip and a fan instead of a compressor, so it can run on a battery, and was planned to sell for about Rs 3,250 (US$69).
Why it mattered. Cooling that suits homes with little money and unreliable power matters as much as a fancy fridge.
Phosphates softened water and helped detergents clean, but in rivers and lakes they feed algae that choke the water. Sixteen US states banned high-phosphate dishwasher detergent in July 2010, and the EU set a strict limit from 1 January 2017.
Why it mattered. Chemists had to invent new recipes that clean well without harming lakes.
India's star labelling programme started in 2006, and washing machines joined it as a voluntary label around 2010, rated from one to five stars. In 2020 the government extended the voluntary phase to 31 December 2021, with plans to make the label compulsory.
Why it mattered. More stars mean less electricity per kilogram of clothes washed, which matters as millions of Indian families buy their first machine.
The Swedish doctor and statistician Hans Rosling told how, when he was four, his mother loaded a washing machine for the first time, and his grandmother, who had washed by hand for seven children, asked to push the button herself. He counted about two billion people with washing machines and five billion who still washed by hand. His mother used the free time to take him to the library.
Why it mattered. He called the washing machine one of the greatest inventions of the industrial revolution because it gave women time to read and learn.
Elica PB India, Franke Faber India and othersPune, India
Elica formed Elica PB India in 2010 with Indian partner Pralhad Bhutada, and Whirlpool of India joined it in 2018. Faber's Indian arm, also based in Pune, says it has been a household name for about 25 years. Hoods catch grease with mesh or baffle filters; a baffle filter makes the smoky air turn sharply, so drops of grease fly out and stick.
Why it mattered. Frying and tadka make lots of oily smoke, so the electric chimney became a common fitting in Indian city kitchens.
Chennai Metropolitan Water Supply and Sewerage BoardMinjur, near Chennai, India
The Minjur plant began turning seawater from the Bay of Bengal into 100 million litres of drinking water a day by reverse osmosis. A second 100 million litre plant at Nemmeli began in 2013. A much bigger 400 million litre plant at Perur is expected around 2027.
Why it mattered. Minjur was India's largest desalination plant when it opened, and it made seawater a real water source for an Indian city.
Companies formed the Wireless Power Consortium in December 2008 and released version 1.0 of its Qi standard in 2010. A coil in the pad and a coil in the phone work like the two halves of Faraday's ring. Qi2, with magnets to line the coils up, followed in 2023.
Why it mattered. Faraday's 1831 ring now sits in millions of phones and chargers.
Vincent Vanhoucke, Andrew Senior and Mark MaoGoogle, Mountain View, United States
For speech recognition, the team ran a neural network with 8-bit integers on ordinary CPUs and got about a 3 times speed-up over a well-tuned floating-point version, with no real loss in accuracy.
Why it mattered. An early, clear sign that inference does not need full-precision numbers.
Epson, followed by other makersIndonesia, then India and the rest of Asia
Epson launched its L100 and L200 ink tank printers in Indonesia in 2010, designed for emerging markets, then brought them to India and other Asian countries. Reports put the Indian launch in 2011 at about ₹9,000. Other makers followed with their own refillable models.
Why it mattered. Bottled ink cut the cost of a page from rupees to paise, which suits students, shops and small offices.
Blackmagic released DaVinci Resolve 8 Lite, a free version with most of the grading tools. Students, YouTubers and small studios could now use the same software as big films. Users grew from about 100 in 2009 to over 2 million by 2019.
Why it mattered. Colour grading went from a rare, costly job to a skill anyone could learn.
Weta Digital, with Andy Serkis as CaesarVancouver, Canada and San Francisco, USA
Rise of the Planet of the Apes took performance capture out of the studio onto real locations, including a battle on a Golden Gate Bridge set. A camera that could see the capture markers in daylight made it possible.
Why it mattered. Mocap no longer needed a dark stage; creatures could act beside live actors on real sets.
Procreate, a painting app for the iPad, was released in 2011. Artists at studios like Disney Animation and Pixar now use it. A sketch can start on a train and end up in a film.
Why it mattered. Concept art tools became portable, cheap and easy to learn.
A young girl in Howrah district, West Bengal, was paralysed by wild poliovirus. She was India’s last case. As recently as 2009, India had 741 cases, the most in the world.
Why it mattered. Many experts had thought India would be the hardest place on Earth to beat polio.
The Dutch company Philips agreed in January 2011 to buy Preethi, which had about 850 workers. Philips said the deal made it the clear leader in a fast-growing part of India's kitchen appliance market.
Why it mattered. Global companies now wanted the Indian mixer grinder, a product invented for India.
Tamil Nadu began giving a free mixer grinder, wet grinder and table fan to families that draw rice from ration shops, aimed at the women who run the kitchen. The first year was meant to cover 25 lakh (2.5 million) families, and by early 2014 about 80 lakh women had received the set.
Why it mattered. It shows the mixie had become an everyday need, not a luxury.
Kooijman, Meijaard, Papadopoulos, Ruina and SchwabDelft, Netherlands, and Ithaca, USA
Writing in Science, the team built a strange bicycle with no gyroscopic effect and no trail, and showed it could still balance itself. What matters is how the bike's mass is arranged, so the front steers into a lean.
Why it mattered. After nearly 200 years, it overturned two popular explanations of why bikes stay up.
Huijuan Cao, Xun Li and Jianping LiuBeijing and Sydney
A review of 135 randomised trials of cupping found possible benefit for a few conditions, such as shingles pain, but most trials were small and of low quality.
Why it mattered. It shows how much better testing is still needed.
Alex Krizhevsky, Ilya Sutskever and Geoffrey HintonUniversity of Toronto, Canada
A deep convolutional network trained on two gaming graphics cards won the ImageNet contest with a top-5 error of about 15.3%, far ahead of about 26.2% for the next team. It used augmentation and dropout to avoid memorising.
Why it mattered. This result convinced much of the field to switch from hand-made features to learned ones.
Alex Krizhevsky, Ilya Sutskever and Geoffrey HintonUniversity of Toronto, Canada
A deep convolutional network with about 60 million weights, trained on two gaming graphics cards, won the ImageNet contest. Its top-5 error was about 15.3 percent, against about 26.2 percent for the best entry from another team. It used dropout, randomly switching off neurons during training, to fight overfitting.
Why it mattered. This result convinced much of the field, and soon the tech industry, that deep learning worked.
Alex Krizhevsky, Ilya Sutskever and Geoffrey HintonUniversity of Toronto
In 2006 and 2007 NVIDIA released CUDA, which let programmers use graphics chips for any kind of maths. In 2012 a neural network called AlexNet, trained on two gaming GPUs, won an image recognition contest by a wide margin.
Why it mattered. It started the modern AI boom, which runs on huge numbers of chips working in parallel.
Peter JacksonWellington, New Zealand, and cinemas worldwide
The Hobbit: An Unexpected Journey was the first widely released feature shot and shown at 48 frames a second, twice the usual 24. About 450 cinemas in North America showed the high frame rate version. Some viewers loved the smooth motion, and others said it looked too real, like video.
Why it mattered. It showed digital projectors could change the frame rate, a choice film projectors had fixed for 85 years.
International Telecommunication Union (ITU)Geneva, Switzerland
Rec. 2020 set the rules for ultra high definition TV. Its colour gamut, the range of colours a screen can show, is far wider than older HD TV. Few screens can show all of it yet, so it acts as a roomy container for the future.
Why it mattered. Graders now deliver the same film in several gamuts, from HD TV to UHD.
S. S. Rajamouli and Makuta VFX, for EegaHyderabad, India
In Eega a murdered man is reborn as a fly and takes revenge. The film had more than 2,000 animation shots. Work on the fly was planned for four months but took fourteen.
Why it mattered. It won the National Film Award for special effects and proved a Telugu film could build its whole story around a digital character.
Dolby LaboratoriesEl Capitan Theatre, Los Angeles, USA
Dolby Atmos was first installed for the premiere of Brave. It adds ceiling speakers and treats sounds as objects with a 3D position, up to 128 tracks and 64 speaker feeds. The cinema's processor decides which speakers play each one.
Why it mattered. Mixers could place a sound anywhere in the room, including overhead.
Eastman Kodak; FujifilmRochester, USA; Tokyo, Japan
Kodak, the biggest maker of film, filed for bankruptcy protection in January 2012. Fujifilm announced it would stop making motion picture film, and ended production in March 2013. By 2013 most top Hollywood films were shot digitally.
Why it mattered. The digital switch was nearly complete, and film became a special choice rather than the default.
John August, Stu Maschwitz and othersUSA and Sweden
Fountain is a simple way to write a screenplay in any text editor, on any device. You type a scene heading, a name in capitals and some dialogue, and software lays it out in proper script format. It is free and open for anyone to use.
Why it mattered. The script format became something anyone could write with no special software at all.
Human Microbiome Project Consortium, NIHAbout 80 institutions, mainly in the USA
The US National Institutes of Health launched the Human Microbiome Project in 2007. Scientists sampled 242 healthy adults at many body sites and read the genes of the microbes they found. In 2012 they published a map of the normal microbes of healthy people, with the gut among the richest places.
Why it mattered. It turned the gut's bacteria from a curiosity into a major field of science.
James Cameron, Deepsea ChallengerMariana Trench, Pacific Ocean
Film-maker James Cameron piloted Deepsea Challenger alone to about 10,908 m. Its steel pilot sphere had been tested to 114 megapascals before the dive. He spent about three hours on the sea floor, the first crewed visit since Trieste 52 years earlier.
Why it mattered. It showed that careful engineering can make the deepest pressure survivable again.
Fred van der Weij (patent) and PhilipsUnited States Patent Office
Van der Weij's US patent for an air guide was granted. Ribs at the bottom of the pan spread out from the middle and turn the hot air upward through the food. Philips calls this shape its starfish design, and says it helps food cook evenly.
Why it mattered. Guiding the air is the trick that lets a small fryer crisp food on all sides.
The latest version of IS 10500, India's drinking water specification, says the acceptable level of total dissolved solids (TDS) is 500 mg per litre. Up to 2,000 mg per litre is permitted when there is no better source.
Why it mattered. This 500 mg per litre line is the number most Indian arguments about RO come back to.
People across northern and eastern India22 states, India
On 30 July the northern grid failed, cutting power to over 400 million people. The next day three regional grids collapsed and over 620 million people lost power, about 9% of everyone on Earth. Homes with charged inverters could keep a few fans and lights on.
Why it mattered. It showed why so many Indian families keep a battery and inverter ready.
In 1996 Carrier sold the first home air conditioner using R-410A, a gas that does not harm ozone but traps a lot of heat. In 2012 Daikin launched air conditioners in Japan using R-32, which Daikin says warms the planet about a third as much as R-410A and needs less gas.
Why it mattered. Each switch kept the same cycle but made the refrigerant kinder to the sky.
The company that put a camera in everyone's hands, and invented the digital camera, entered bankruptcy as film sales collapsed. It later re-emerged as a much smaller company.
Why it mattered. A famous lesson in how technology can overtake its own inventors.
WHO's Traditional Medicine Strategy 2014–2023 asked countries to build evidence, regulate products and practitioners, and integrate traditional medicine safely.
Why it mattered. It set the global frame of safety, quality and evidence for systems like Siddha.
Tomas Mikolov and colleagues at GoogleMountain View, United States
word2vec learned word vectors quickly from billions of words. Famously, king − man + woman landed near queen. Later studies found such sums work less neatly than the headlines said, and that the vectors carry social biases.
Why it mattered. Embeddings became the standard first layer of every language model.
Claudio Miranda, Joseph Kosinski and Digital DomainUSA
For Oblivion's glass sky tower set, 21 projectors threw filmed clouds onto a seamless white screen 152 m long and 13 m tall, wrapped 270° around the set. The footage was shot from a Hawaiian mountain top with three cameras side by side.
Why it mattered. It lit the glass set with its own sky and captured the reflections in camera, the core idea of an LED volume.
Framestore, Emmanuel Lubezki and Alfonso CuarónEngland, UK
For Gravity, actors sat inside a cube lined with LED panels, reported as 1.8 million individually controlled LEDs. The panels played the light of the Earth, the Sun and stars moving around them, so their faces were lit exactly as the CG world demanded.
Why it mattered. It proved that LED screens could be the lighting, not just the background.
Monsters University is described as Pixar's first film to use global illumination, with light bouncing around scenes lit by hundreds of lamps. Pixar's Sanjay Bakshi said a frame took about 29 hours to render on a farm of 2,000 computers with over 24,000 cores. The whole film reportedly used over 100 million CPU hours.
Why it mattered. Simulating real light made lighting easier for artists but hugely more expensive to compute.
Alexey Stomakhin, Craig Schroeder, Lawrence Chai, Joseph Teran and Andrew SelleWalt Disney Animation Studios and UCLA, Los Angeles
For Frozen, Disney and UCLA mathematicians built a new snow simulator using the material point method. Snow could pack, crumble and break apart like the real thing, instead of being faked with particles.
Why it mattered. Simulation research now happens inside film studios, and it is published for everyone.
Gilead Sciences, building on the work of many scientistsUSA
In December 2013 the drug sofosbuvir was approved in the United States. In October 2014 it was combined with ledipasvir in a single daily pill, and trials cured 94 to 99 percent of patients. Old interferon injections had cured only about half of patients at best and made people feel very ill.
Why it mattered. A virus that caused cirrhosis and liver cancer became curable with a short course of pills.
Ed Currie, PuckerButt Pepper CompanySouth Carolina, USA
Guinness World Records confirmed the Carolina Reaper, a cross-bred chilli, as the hottest, at an average of 1,569,300 Scoville heat units; a 2017 re-test put it at 1,641,183.
Why it mattered. Breeders were now deliberately crossing chillies to push the heat higher.
Neurologists described 26 people who collapsed, had fits or were poisoned by carbon monoxide while bathing in closed bathrooms with gas geysers that had no flue. The cases came in the winters of 2008 to 2010.
Why it mattered. It warned families that a gas geyser needs a flue or good ventilation, the same danger Maughan's geyser had in 1868.
LG began taking orders for a 55-inch OLED TV, the 55EM9700, just 4 mm thick. Each pixel had red, green, blue and an extra white sub-pixel. It cost about US$10,000.
Why it mattered. Big OLED TVs with perfect blacks became a real product you could buy.
New standard-size dishwashers sold in the US could use no more than 5.0 gallons (about 19 litres) of water per cycle and 307 kWh of electricity a year.
Why it mattered. Rules made sure even the cheapest machines stopped wasting water.
The Sorek plant opened with a capacity of 624,000 cubic metres of drinking water a day, making it the world's biggest seawater RO plant at the time. It stacks huge 16-inch membrane tubes upright to save space.
Why it mattered. It showed seawater RO could supply a large share of a whole country's tap water.
Ministry of Health, WHO, Rotary, UNICEF and millions of vaccinatorsNew Delhi
Pulse Polio days sent oral polio drops to every child, even on trains and at bus stands. India’s last case of wild polio was a girl in Howrah in January 2011. After three years with no cases, WHO certified the South-East Asia region polio-free.
Why it mattered. Few thought it possible in a country so large and crowded; it showed what vaccines and persistence can do.
The Department of AYUSH, created as ISM&H in 1995 and renamed in 2003, became a full Ministry of AYUSH, covering Ayurveda, Yoga, Unani, Siddha, Sowa-Rigpa and Homoeopathy.
Why it mattered. Unani got a place at the top of India’s health administration.
The department for Indian systems of medicine and homeopathy became a full ministry: AYUSH, for Ayurveda, Yoga and Naturopathy, Unani, Siddha, Sowa-Rigpa and Homoeopathy.
Why it mattered. Homeopathy sits beside Ayurveda, Unani and Siddha as an official system in India.
Ian Goodfellow and colleaguesUniversité de Montréal, Canada
In a generative adversarial network (GAN), one network makes fake images and another tries to spot them. Each gets better by competing with the other. A year earlier, Kingma and Welling had shown the variational autoencoder, another way to generate pictures.
Why it mattered. For the first time, networks could invent new, realistic-looking images instead of only sorting them.
Yaniv Taigman and colleaguesFacebook AI Research, Menlo Park, United States
A deep network trained on about 4 million face photos from Facebook users matched pairs of faces with 97.35% accuracy on a standard test, close to the 97.53% people score.
Why it mattered. Face recognition jumped in accuracy, and so did questions about who gets recognised, and with whose photos.
Ilya Sutskever, Oriol Vinyals and Quoc LeGoogle, Mountain View, United States
An LSTM read a whole sentence into one vector, and a second LSTM wrote the translation from it. It worked surprisingly well, but long sentences were hard to squeeze into one vector.
Why it mattered. It showed that one network could learn to map any text to any text.
Dzmitry Bahdanau, Kyunghyun Cho and Yoshua BengioUniversité de Montréal, Canada
Instead of one squeezed vector, the translator learned to look back at the most relevant source words for each word it wrote. The paper was presented at ICLR in 2015.
Why it mattered. Attention solved the long-sentence problem and became the heart of the transformer.
Paramount became the first major Hollywood studio to stop sending 35 mm prints to US cinemas: Anchorman 2 was its last film release, and The Wolf of Wall Street went out only as digital files. About 92% of US screens were already digital. By the end of 2014, about 90% of the world's cinema screens were digital.
Why it mattered. Once studios stopped making prints, film projectors went quiet in almost every cinema on Earth.
Christie and IMAXSeattle, USA, and Toronto, Canada
Christie installed what it called the first permanent laser cinema projector at the Seattle Cinerama in early 2014, after demonstrations in 2012 and 2013. In December 2014 IMAX with Laser opened in Toronto. Red, green and blue lasers replace the xenon lamp, giving brighter, more colourful light that barely fades with age.
Why it mattered. Lasers made 3D and giant screens bright enough, and are slowly replacing lamps in cinemas everywhere.
Dolby designed a new curve called PQ, built around how our eyes see brightness, and SMPTE published it as ST 2084 in 2014. It can describe light up to 10,000 nits, about a hundred times brighter than a normal TV picture. Dolby Vision, the first HDR format, was introduced the same year.
Why it mattered. Colourists now grade two versions of many films: one for normal screens and one for bright HDR screens.
Academy of Motion Picture Arts and SciencesLos Angeles, USA
Every camera records colour in its own way, which makes mixing them hard. ACES gives every shot a shared, huge colour space whose widest version holds every colour the eye can see. Version 1.0 came out in December 2014, after about ten years of work by around 50 experts.
Why it mattered. It lets a film's colour survive from camera to grading to cinema without getting lost.
Soundarya Rajinikanth, with RajinikanthChennai, India, and Pinewood Studios, London, UK
Kochadaiiyaan was captured at the Centroid lab at Pinewood Studios with 48 cameras, and Rajinikanth performed his triple role in a marker suit. Big Indian effects films such as Ra.One (2011) and Baahubali (2015) also leaned on VFX, though published accounts say little about how much mocap each used.
Why it mattered. It was billed as India's first photorealistic motion-capture feature.
Namit Malhotra's Prime Focus World and Double NegativeMumbai, India, and London, UK
Prime Focus World merged with Double Negative, a London studio that had won an Oscar for Inception. The combined company, DNEG, grew studios across many Indian cities. It has since won Oscars for films like Interstellar, Dune and Dune: Part Two.
Why it mattered. It showed that big Hollywood effects are now often made by Indian artists, working in India.
Prime Focus (Namit Malhotra) and Double NegativeMumbai, India, and London, UK
Prime Focus World, part of Mumbai's Prime Focus, merged with the London studio Double Negative, creating a company of about 4,500 people. Now called DNEG, it runs studios in many Indian cities. It has won Oscars for the visual effects of films including Interstellar, Tenet and both Dune films.
Why it mattered. Big film rendering became a global team effort, with India doing a large share of the work.
Walt Disney Animation StudiosBurbank, California, USA
Disney built a new path tracer called Hyperion for Big Hero 6, with light bouncing many times through the city of San Fransokyo. It could show light shining through the robot Baymax's soft vinyl skin. Disney used a farm of over 2,300 computers in four data centres.
Why it mattered. A second big studio switched to path tracing for a whole animated film.
US Federal Aviation Administration; six aerial film companiesUSA
The FAA gave six aerial photography companies permission to fly small camera drones on film and TV sets, with rules like no night flying. Cheap, stable drones, such as the DJI Inspire series from China, soon replaced many helicopter shots.
Why it mattered. Sweeping aerial shots became affordable for almost any production.
After three years with no wild polio cases, the WHO certified the South-East Asia Region, including India, polio-free. Children in India still get polio vaccine, because the virus survives in a few other countries.
Why it mattered. It showed that high vaccine coverage can wipe a disease out even in a huge, crowded country.
Liu Zhongjun and teamPeking University Third Hospital, Beijing
A 12-year-old boy had a tumour in the second bone of his neck. Surgeons replaced it with a titanium vertebra printed to match his own. Tiny pores in the metal let his real bone grow into it.
Why it mattered. Printed implants can be shaped for one person and joined by living bone.
India launched a five-year mission to end open defecation. By 2 October 2019 all states had declared themselves open-defecation free, after more than 100 million household toilets were built in villages.
Why it mattered. It was the largest toilet-building programme in history.
Herbert Helander and Lars FändriksUniversity of Gothenburg
Textbooks often said the inside of the gut had the area of a tennis court. Helander and Fändriks measured it carefully under the microscope and found about 30 to 40 square metres, about 32 on average, almost all of it in the small intestine.
Why it mattered. It fixed a famous wrong number, though the gut’s folds, villi and microvilli still make its surface huge.
Ardem Patapoutian and teamLa Jolla, California, USA
Ardem Patapoutian's team tested gene after gene to find sensors that open when a cell is pressed, and found Piezo1 and Piezo2 in 2010. In 2014 they showed that Piezo2 is the main sensor for light touch in mouse skin. Patapoutian, born in Lebanon, shared the 2021 Nobel Prize with David Julius.
Why it mattered. It found the switch that turns a gentle press on the skin into a nerve signal.
Herbert Helander and Lars FändriksUniversity of Gothenburg, Sweden
Textbooks often said the inside of the gut had the area of a tennis court, about 260 to 300 square metres. Helander and Fändriks measured it carefully under the microscope and got about 30 to 40 square metres, about 32 on average. Almost all of it is in the small intestine.
Why it mattered. It fixed a famous wrong number, though the gut's folds, villi and microvilli still make its surface huge.
Caroline Bushdid, Andreas Keller, Leslie Vosshall and colleaguesRockefeller University, New York, USA
Volunteers compared mixtures of many odour molecules and tried to spot the odd one out. From the results the team estimated that people can tell apart at least a trillion different smells, and the number made headlines.
Why it mattered. It overturned the old, never-tested claim that humans can tell apart only about 10,000 smells.
By 2009 a new American fridge used about 450 kWh a year, half as much as in 1990, says the US Energy Information Administration. New national standards in September 2014 cut the energy use of most fridges and freezers by another 20 to 25%. Since the 1970s, energy use has fallen by more than three quarters while fridges have grown bigger.
Why it mattered. Steady rules and better engineering made the fridge one of the great energy-saving stories.
Netflix began streaming the second season of House of Cards in 4K, with four times the pixels of Full HD. It only worked on new smart TVs with streaming apps and newer video compression built in. More and more, TV came through the internet instead of an antenna.
Why it mattered. The picture on a TV now depended on the internet as much as on the screen.
Ruben Meerman and Andrew BrownUniversity of New South Wales, Sydney
Meerman, a physicist, and Brown, a chemist, followed every atom in 10 kg of body fat as it is burned. They found that 8.4 kg leaves as carbon dioxide through the lungs and 1.6 kg as water. Many doctors and trainers they surveyed had guessed it turned into energy or heat.
Why it mattered. It is Lavoisier's law applied to your own body: mass lost has to go somewhere.
ISRO, Mars Orbiter MissionLaunched from Sriharikota
India's PSLV rocket was too small to fling the spacecraft straight to Mars. So it circled Earth, firing its engine seven times to stretch its orbit, then set off on a 298-day coast to Mars.
Why it mattered. It made India the first Asian nation to reach Mars orbit, using Newton's laws to save fuel.
The UN General Assembly adopted India's proposal on 11 December 2014, backed by 177 countries. The first day was held on 21 June 2015, with a record mass session on Rajpath, New Delhi.
Why it mattered. Yoga, the partner of naturopathy in AYUSH, became a worldwide annual event.
National Health and Medical Research CouncilCanberra
After looking at 176 studies across 61 conditions, the NHMRC concluded there were no health conditions with reliable evidence that homeopathy was effective. Homeopathy groups disputed its methods; the NHMRC stood by its findings.
Why it mattered. It is the most-cited government review of homeopathy.
Jascha Sohl-Dickstein, Eric Weiss, Niru Maheswaranathan and Surya GanguliStanford University, United States
Borrowing an idea from physics, the team slowly destroyed images by adding noise, then trained a network to run the process backwards. The results were blurry and the idea was mostly ignored for five years.
Why it mattered. It was the seed of diffusion, the method behind most video models today.
Kaiming He, Xiangyu Zhang, Shaoqing Ren and Jian SunMicrosoft Research Asia, Beijing, China
Very deep networks used to train badly. ResNet added shortcut connections that let each block learn only a small change, which made networks 152 layers deep trainable. It won ImageNet 2015 with a 3.57% top-5 error.
Why it mattered. Residual connections are now in almost every large network, including language models.
Olaf Ronneberger, Philipp Fischer and Thomas BroxUniversity of Freiburg, Germany
U-Net shrinks a picture through convolution layers and then grows it back, labelling every pixel. It was built to outline cells in microscope images from only a few labelled examples.
Why it mattered. It became a standard tool for segmentation, especially in medicine.
Distillation: a small student copies a big teacher
Geoffrey Hinton, Oriol Vinyals and Jeff DeanGoogle, Mountain View, United States
The paper showed how to train a small model to copy the full answer probabilities of a big one, keeping much of its skill in a model that is far cheaper to run.
Why it mattered. Distillation is now a standard way to make models small enough for phones and busy servers.
Rico Sennrich, Barry Haddow and Alexandra BirchUniversity of Edinburgh, United Kingdom
The team borrowed a 1994 compression trick, byte-pair encoding, to split rare words into common pieces for translation. Published at ACL in 2016, it became how most LLMs make their tokens.
Why it mattered. Subword tokens let models handle any word, even ones they never saw.
TRAI's figures showed India's wireless subscriptions passing 1 billion (1.01 billion) by the end of 2015, with total phone connections having crossed 1 billion that May. Many people had more than one SIM.
Why it mattered. India became the second country, after China, with a billion mobile connections.
Most end-of-the-world films looked grey and washed out. For Mad Max: Fury Road, Miller asked for rich, graphic colour by day and deep blue nights. Whipp graded and sharpened shots one by one to get that comic-book punch.
Why it mattered. It is one of the best known examples of a grade breaking the genre's rules.
S. S. Rajamouli, V. Srinivas Mohan, Makuta VFX and others, for Baahubali: The BeginningRamoji Film City, Hyderabad, India
Huge sets for Mahishmati were built at Ramoji Film City, then extended digitally into a whole kingdom. More than 600 artists at 18 facilities worked on effects, including a giant waterfall and a war. In one scene, about 3,000 people on set were made to look like 50,000.
Why it mattered. It proved an Indian film could do world-class set extension and crowds, and it won the National Film Award for special effects.
The team built around 150 working vehicles for the desert chases, and only 88 survived filming. Stunt coordinator Guy Norris led more than 150 stunt performers. The film is reported to have done about 90 per cent of its effects for real, then won six Oscars.
Why it mattered. It proved that real vehicles and real stunts could still thrill audiences in the CGI age.
ARRI launched the SkyPanel at NAB in April 2015 and began shipping it that September. The S60 was brighter than a 2 kW tungsten soft light, and its colour could be tuned from 2,800 K to 10,000 K, or set to almost any hue. LED panels like it are now on nearly every film set.
Why it mattered. One LED fixture can replace a whole box of lamps and coloured gels.
Tangerine was shot on three iPhone 5s phones with a clip-on anamorphic adapter lens. It premiered at the Sundance Film Festival in 2015 and won praise from critics. The money saved on cameras paid for locations and extras.
Why it mattered. The camera in your pocket had become good enough to make a real feature film.
For Baahubali: The Beginning, production designer Sabu Cyril designed a whole kingdom, including thousands of weapons and armour pieces. About 15,000 storyboard sketches were made before filming. VFX studios such as Makuta VFX in Hyderabad then built its biggest sights.
Why it mattered. It showed Indian cinema designing fantasy worlds at the same scale as Hollywood.
Firefly Creative Studio; V. Srinivas Mohan and the RRR teamHyderabad, India
For Baahubali (2015), VFX supervisor Sanath PC of Firefly Creative Studio said the team did a lot of pre-vis for the war scenes, so the director, fight master and cinematographer worked from one plan. For the animal stampede in RRR (2022), pre-vis worked out how fast each animal would run, and those numbers drove a strip of LED lights on set.
Why it mattered. Big Indian action films now rehearse their most expensive shots in 3D before a single camera rolls.
Baahubali: The Beginning (2015) and Baahubali 2 (2017) were Telugu epics released in several languages. The second film had close to 2,500 VFX shots made by about 35 studios, and was the first Indian film reported to earn over ₹1,000 crore worldwide.
Why it mattered. It proved Indian films could build huge visual effects and reach audiences across India and abroad.
Cordelia Running, Bruce Craig and Richard MattesPurdue University, USA
Taste tests suggested that fatty acids have a taste of their own, which the team proposed calling "oleogustus". Earlier work had found fat-sensing receptors such as CD36 on taste cells. Scientists still debate it, along with "kokumi", a richness linked to a calcium-sensing receptor.
Why it mattered. The list of basic tastes may not be finished.
Richard Gerkin and Jason Castro; Markus MeisterUSA
Two papers showed that the trillion figure depended heavily on the maths used. With the same method, the answer could be far bigger or far smaller, and applied to colour vision it gave nonsense. The true number of smells we can tell apart is still unknown.
Why it mattered. Big numbers need careful checking: the question is still open.
India's Bureau of Energy Efficiency made star labels compulsory for electric storage geysers of up to 200 litres, after a voluntary phase. The stars rate standing loss: the electricity a full, idle geyser uses in 24 hours just to stay hot. The government's formal notice followed in September 2016.
Why it mattered. Better insulation earns more stars, so every geyser sold now tells buyers how much heat it leaks.
LIGO Scientific Collaboration and VirgoLivingston, Louisiana, and Hanford, Washington, USA
Both LIGO detectors caught a brief chirp: gravitational waves from two black holes, about 35 and 30 times the Sun's mass, merging about 1.4 billion light years away. Their 4 km arms changed length by about a thousandth of a proton's width. The 2017 Nobel Prize in Physics went to Rainer Weiss, Barry Barish and Kip Thorne.
Why it mattered. It confirmed the last big prediction of Einstein's gravity and opened a new way to observe the universe.
The government asked better-off families to give up their LPG subsidy voluntarily. By April 2016 about 1 crore people had done so. The money was used to help pay for gas connections for poor households.
Why it mattered. It linked city kitchens to village kitchens and paved the way for Ujjwala.
LIGO teamHanford, Washington and Livingston, Louisiana
Two detectors caught a gravitational wave from two black holes merging 1.4 billion light-years away. It stretched the 4 km arms by a thousandth of a proton's width, chirping from 35 to 250 Hz in a fifth of a second.
Why it mattered. Einstein's last untested prediction was confirmed, opening a new way to observe the universe; the leaders won the 2017 Nobel Prize.
BIS published IS 16240, the Indian Standard for reverse osmosis purifiers used at home. Purifiers certified under it are tested for things such as how well they clean water and how much of the input water they recover.
Why it mattered. It gave buyers a way to trust a purifier, and put water wastage into the rulebook.
Ayurveda Day is held on Dhanvantari Jayanti. The first one focused on diabetes, and in 2017 the All India Institute of Ayurveda in New Delhi was dedicated to the nation on the same day.
Why it mattered. It gave Ayurveda a yearly national spotlight and a flagship institute.
Carl Vondrick, Hamed Pirsiavash and Antonio TorralbaMIT, Cambridge, United States
Trained on over two million unlabelled videos, VGAN generated clips of 32 frames at 64 by 64 pixels, up to about a second long. It learned to draw a still background and a moving foreground separately. The paper appeared at NeurIPS 2016.
Why it mattered. It showed a network could learn how scenes move, not just how they look.
Joseph Redmon, Santosh Divvala, Ross Girshick and Ali FarhadiUniversity of Washington and Allen Institute for AI, Seattle, United States
Instead of sliding a window, YOLO splits the picture into a grid and predicts all boxes and classes in one pass of one network. It ran at about 45 frames a second.
Why it mattered. Fast single-pass detectors made real-time detection practical in cars, drones, phones and cameras.
Norman Jouppi and a Google teamGoogle, Mountain View, United States
Google revealed its Tensor Processing Unit, already running in its data centres since 2015. Its heart was a grid of 65,536 8-bit multiply-add units, reaching 92 trillion operations a second. Google reported 15 to 30 times the speed of the CPUs and GPUs it then used, for its inference jobs.
Why it mattered. It proved that a chip made mostly of multiply-add units, using small numbers, is the efficient way to run trained networks.
NVIDIA's GPU Inference Engine, renamed TensorRT in September 2016, took a trained network and rebuilt it to run fast: merging layers, choosing the best maths routines and using lower precision such as INT8.
Why it mattered. Inference became its own engineering job, with its own tools, separate from training.
AlphaGo, which used neural networks to judge positions and pick moves, beat Lee Sedol, one of the world's best Go players, by 4 games to 1. Its move 37 in game 2 surprised experts. Lee won game 4 with a brilliant move of his own.
Why it mattered. Go has more possible positions than atoms in the universe, so this showed learned intuition could beat brute force.
Reliance Jio launched a 4G-only network with free voice calls and months of free data. Rivals slashed prices. According to TRAI, the average price of 1 GB fell from about ₹269 in 2014 to about ₹12 in 2018.
Why it mattered. Hundreds of millions of Indians came online for the first time, on phones, and India became one of the world's biggest users of mobile data.
The BBC and Japan's NHK designed hybrid log gamma (HLG), an HDR curve that still looks fine on older TVs. Japan published it as a standard in July 2015. In July 2016 the ITU put both HLG and PQ into its Rec. 2100 standard.
Why it mattered. Broadcasters could now send one HDR signal to everyone, which matters for live sport and news.
Jon Favreau, Rob Legato, Bill Pope and Glenn Derry's teamLos Angeles Center Studios, USA
The Jungle Book was shot entirely on stages in Los Angeles, with one young actor, Neel Sethi. A tracked 'Simulcam' system showed the camera operators a rough version of the CG jungle and animals in real time, laid over the live picture.
Why it mattered. Tracking a real camera and drawing the virtual world from its point of view, live, became normal practice.
Ninja Theory, Epic Games, Cubic Motion and 3LateralAnaheim, California, USA (SIGGRAPH)
On stage at SIGGRAPH, actress Melina Juergens performed as Senua from the game Hellblade. Her body and face were captured and rendered live in a game engine, then cut into a finished scene in minutes. It won Best Real-Time Graphics and Interactivity.
Why it mattered. Game engines made real-time performance capture good enough to be close to final.
Finding Dory was Pixar's first feature to fully adopt RenderMan's new RIS system, a path tracer, replacing the Reyes method used since Toy Story. It also used a denoiser from Disney Research to clean up grainy frames. Lighters could fill fish tanks with dozens of physical lights.
Why it mattered. The studio that invented much of CGI rendering moved fully to simulating light.
For Kubo and the Two Strings, LAIKA built a giant skeleton puppet about 16 feet (almost 5 m) tall, moved by motion-control rigs. The studio printed about 64,000 faces for the film.
Why it mattered. LAIKA calls it the largest stop-motion puppet ever made.
Toonz, first made in Italy in 1993 and customised for Studio Ghibli, was released free as OpenToonz. Ghibli had used it on films such as Princess Mononoke and Spirited Away.
Why it mattered. Studio-grade 2D tools became free for anyone to learn on.
The Ministry of Health and Family Welfare launched PMSMA, which offers every pregnant woman in her second or third trimester a free check-up by a doctor on the 9th day of every month at government health centres.
Why it mattered. Regular check-ups catch problems like high blood pressure and anaemia before they become dangerous.
Ron Sender, Shai Fuchs and Ron MiloWeizmann Institute of Science, Rehovot
People had long said bacteria outnumber our cells ten to one, a rough guess from 1972. Sender, Fuchs and Milo worked it out again: about 38 trillion bacteria and 30 trillion human cells in a typical adult, most of the bacteria in the colon.
Why it mattered. We are roughly half microbe by cell count, not ninety percent.
Ministry of Health and Family WelfareNew Delhi, India
India launched e-RaktKosh on World Health Day, an online system that links blood centres so people can see where blood of each group is available. By 2024 India was collecting about 1.46 crore (14.6 million) units a year.
Why it mattered. It helps blood reach patients faster and wastes less.
India launched the Pradhan Mantri National Dialysis Programme under the National Health Mission, to give free dialysis to poor patients at district hospitals. By the end of 2022 it ran in all 36 states and union territories.
Why it mattered. Dialysis moved closer to home for many families who could not afford it.
The MiniMed 670G became the first 'hybrid closed loop' system approved in the US: a glucose sensor and an insulin pump linked by software that adjusts background insulin automatically. People still had to tell it about meals.
Why it mattered. It was a first step towards an artificial pancreas.
World Health Assembly (WHO member states)Geneva, Switzerland
All 194 WHO member states agreed a plan to eliminate viral hepatitis as a public health threat by 2030. That means cutting new infections by 90 percent and deaths by 65 percent.
Why it mattered. It was the first time the whole world set a deadline for beating hepatitis.
Ron Sender, Shai Fuchs and Ron MiloWeizmann Institute of Science, Rehovot, Israel
For decades people said bacteria outnumber our own cells ten to one, a rough guess that goes back to a 1972 estimate. Sender, Fuchs and Milo worked it out again and found about 38 trillion bacteria and 30 trillion human cells in a typical adult. Most of the bacteria live in the large intestine.
Why it mattered. It showed we are roughly half microbe by cell count, not ninety percent.
Brien Holden Vision Institute (Holden et al.)Sydney
A study pooling data from around the world estimated that about 23% of people were short-sighted in 2000 and projected about 50%, nearly five billion people, by 2050, driven by more near work and less time outdoors.
Why it mattered. It made myopia a global public health concern, especially in children.
India's first home-built nuclear-powered ballistic missile submarine was launched on 26 July 2009 and commissioned in August 2016. It displaces about 6,000 tonnes on the surface and, like every submarine, dives by flooding its ballast tanks.
Why it mattered. It shows the same Archimedes balance working in a 6,000-tonne vessel.
Meeting in Rwanda, nearly 200 countries agreed to cut back HFCs, the ozone-safe refrigerants in many fridges that are powerful greenhouse gases. Doing so could avoid up to about 0.5 °C of warming by 2100.
Why it mattered. The ozone treaty became a climate treaty too.
Pradhan Mantri Ujjwala Yojana set out to give 5 crore free LPG connections to women in poor families. It passed that goal, handed over the 8 crore connection on 7 September 2019, and reached 10.33 crore by March 2025. Keeping families buying refills has been the harder part.
Why it mattered. It was one of the fastest moves from smoky chulhas to clean flames anywhere in the world.
Meeting in Rwanda, nearly 200 countries agreed to cut back HFCs, the ozone-safe refrigerants that are powerful greenhouse gases. Doing so could avoid up to about 0.5 °C of warming by 2100.
Why it mattered. The ozone treaty became a climate treaty too.
During a large dengue outbreak, Tamil Nadu handed out Nilavembu kudineer, a nine-herb Siddha decoction, free to the public. Scientists and journalists asked for proper trials, and lab studies later showed antiviral effects in cells.
Why it mattered. It made a Siddha remedy part of public health and started a debate about evidence.
A national pharmacovigilance scheme for Ayurveda, Siddha, Unani and Homoeopathy medicines began, with a national centre at the All India Institute of Ayurveda and reporting centres across the country.
Why it mattered. Side effects of Siddha medicines can now be reported and studied.
After a public consultation, NHS England told local health bodies to stop routinely prescribing homeopathy, citing a lack of robust evidence. The High Court rejected a challenge in 2018.
Why it mattered. One of the health services where homeopathy had the longest history stepped back from it.
A user called "deepfakes" posted videos in which one person's face had been swapped onto another's using neural networks, and shared the code. The name stuck for any AI-faked video. Most early deepfakes targeted women without their consent.
Why it mattered. Faked video became a public worry years before text-to-video models existed.
Microsoft and Facebook, later joined by AWS and othersRedmond and Menlo Park, United States
ONNX let a model trained in one framework be saved and run in another. In December 2018 Microsoft open-sourced ONNX Runtime, an engine for running such models on many kinds of hardware.
Why it mattered. Training tools and inference engines could now be mixed and matched.
Apple (A11 Bionic); Huawei had announced its Kirin 970 with an NPU days earlierCupertino, United States; Shenzhen, China
The iPhone X's A11 chip included a two-core Neural Engine that Apple said could do 600 billion operations a second, used for Face ID and Animoji. Huawei's Kirin 970, shown at IFA Berlin that month, also had a neural processing unit.
Why it mattered. Phones got their own inference hardware, so AI could run without the cloud.
Brendan McMahan, Daniel Ramage and colleaguesGoogle, Seattle and Mountain View, United States
Google tested federated learning in its Gboard keyboard: phones improve a small shared prediction model locally and send only updates, not what you typed. The keyboard's next-word model itself runs on the phone.
Why it mattered. A clear example of useful, private, on-device inference.
The team described how to run networks using only 8-bit integer arithmetic, and how to train them so accuracy holds up. The method went into TensorFlow Lite, used to run models on phones.
Why it mattered. INT8 became the everyday standard for running AI on phones and many servers.
Ashish Vaswani and seven co-authors at GoogleMountain View, United States
The transformer dropped step-by-step reading and used only attention, so every word could look at every other word at once. It trained much faster on GPUs and beat earlier translators.
Why it mattered. Almost every modern LLM, from GPT to Claude, Gemini and Llama, is a transformer.
Paul Christiano, Jan Leike and colleaguesOpenAI and DeepMind
Researchers trained an agent from people's choices between pairs of short video clips, instead of a written score. This reinforcement learning from human feedback (RLHF) later shaped chatbots.
Why it mattered. It gave builders a way to tune models towards what people actually prefer.
Ashish Vaswani and seven co-authorsGoogle Brain and Google Research, Mountain View, United States
Eight researchers at Google described the transformer, a network that lets every word look at every other word through "attention". It trained fast on many chips at once. Our box LLMClear explains how it works.
Why it mattered. Transformers became the engine of today's chatbots and large language models.
A national survey of US hospital doctors and other clinicians found that about 80% were given a pager by their hospital, and pagers were the most common way they received patient messages.
Why it mattered. Reliable coverage indoors keeps pagers in hospitals.
England's health service was reported to be the world's largest purchaser of fax machines. In December 2018 the government banned it from buying new ones from January 2019 and set 31 March 2020 as the date to phase them out.
Why it mattered. It showed how long fax lasts in hospitals, where a phone number and a delivery report feel safe.
Samsung and Lotte CinemaLotte Cinema World Tower, Seoul
Samsung's Onyx, the first LED cinema screen, opened at Lotte Cinema World Tower in Seoul. The screen is made of millions of tiny LEDs that make their own light, so there is no projector, lamp or lens at all. India's first Onyx screen opened at PVR Icon in Vasant Kunj, Delhi, in 2018.
Why it mattered. For the first time since the magic lantern, a cinema picture did not have to be thrown across a room.
Zhe Cao, Yaser Sheikh and team, Carnegie Mellon UniversityPittsburgh, USA
OpenPose was the first open-source system to find the body keypoints of many people in ordinary video in real time, using deep learning and part affinity fields.
Why it mattered. It started the markerless wave: pose from video, no suit.
The iPhone X's TrueDepth camera projects over 30,000 invisible infrared dots onto the face. Apple's ARKit turns them into 52 blend-shape weights, such as jaw open and brow up, many times a second.
Why it mattered. Facial capture that once needed a studio became something anyone could try at home.
R. C. Kamalakannan and Makuta VFX, for Baahubali 2: The ConclusionHyderabad, India
Baahubali 2 had close to 2,500 effects shots, split into about 13,500 separate tasks. Around 35 studios around the world each got the jobs they were best at, such as clouds or water. Makuta built the look of Mahishmati.
Why it mattered. It showed how one huge film can be shared out across studios on different continents.
Nvidia, and researchers at Disney, Pixar and elsewhereUSA and Zurich, Switzerland
With only a few rays per pixel, a path-traced image looks grainy. Nvidia added an AI denoiser to its OptiX software, trained on tens of thousands of rendered images. The same year, a team from Disney, Pixar and university partners published a neural network that denoises film frames.
Why it mattered. Denoisers let renderers stop early, saving huge amounts of time.
A review in Science traced the idea that humans are poor smellers back to Broca, and showed that in tests people can match or beat dogs and rodents at detecting some smells.
Why it mattered. It helped end a 140-year-old myth about the human nose.
In the year to March 2017, India's makers sold about 17.7 million two-wheelers at home, more than the 16.8 million sold in China. Most were 100–110 cc commuter motorcycles and scooters.
Why it mattered. India is now where most of the world's new motorcycles and scooters go.
The MAGNETOM Terra became the first 7 T scanner cleared for clinical use: in Europe in August 2017 and by the US FDA on 12 October 2017, for the head and limbs.
Why it mattered. Ultra-high fields reach finer detail, such as tiny lesions in the brain.
Food Standards Agency and Denise LewisUnited Kingdom
In 2015 the European Food Safety Authority confirmed that acrylamide in food may raise cancer risk for people of all ages. The UK Food Standards Agency then launched a campaign with Olympic champion Denise Lewis. It told families to cook chips, roast potatoes and toast to a golden yellow, not dark brown.
Why it mattered. Golden, not burnt, became the target colour for anyone frying, baking or air frying.
The EU adopted Regulation 2017/2158, which from 11 April 2018 made food businesses take steps to keep acrylamide low. For French fries it set a benchmark level of 500 micrograms per kilogram. Kitchens were told to use colour guides and the right frying temperatures.
Why it mattered. Controlling heat and browning became a legal duty, not just good cooking.
Philips said it had sold more than 7 million Airfryers since the launch. Rival brands and cheaper copies were appearing everywhere. Celebrity chefs demonstrated air fryers on TV shopping channels and YouTube.
Why it mattered. The air fryer had become a whole product category, not just one gadget.
Siddha Day was first marked on the traditional birthday of Agathiyar, the Ayilyam star in the Tamil month of Margazhi. Its date moves each year with the Tamil calendar.
Why it mattered. It gave Siddha a national day, like Ayurveda Day and Unani Day.
Neurologists reported 32 patients with high blood mercury and severe nerve pain after taking unauthorised Siddha medicines. A 2021 NIMHANS review counted 220 heavy-metal poisoning cases linked to Indian traditional medicines.
Why it mattered. Indian doctors documented the risks of badly made metal medicines.
Government of India, National Health AuthorityRanchi, Jharkhand (launch)
The Pradhan Mantri Jan Arogya Yojana began covering hospital care of up to ₹5 lakh per family per year for poorer families. In 2024 it was extended to everyone aged 70 or over. Alongside it, sub-centres and PHCs are being upgraded to Ayushman Arogya Mandirs.
Why it mattered. It is one of the world’s largest government health-insurance schemes, aimed at the heavy out-of-pocket costs Indian families pay.
Joy Buolamwini and Timnit GebruMIT Media Lab, Cambridge, United States
Testing three commercial face-analysis systems on 1,270 faces of parliament members from six countries, they found gender errors of at most 0.8% for lighter-skinned men but up to 34.7% for darker-skinned women.
Why it mattered. It showed that unbalanced data can make a system fail most for the people least represented, and pushed companies to improve.
Alec Radford and colleagues at OpenAISan Francisco, United States
OpenAI pretrained a 117-million-parameter transformer on books to predict the next token, then fine-tuned it for tasks. The Generative Pre-trained Transformer was born.
Why it mattered. Pretraining on plain text, then adapting, became the standard recipe.
Jacob Devlin and colleagues at GoogleMountain View, United States
BERT learned by filling in hidden words using the text on both sides. Fine-tuned, it topped many language tests, and Google began using it in Search in 2019.
Why it mattered. It showed how much pretrained transformers knew about language.
India's policy think tank NITI Aayog published a discussion paper, the National Strategy for Artificial Intelligence. It picked five areas where AI could help most: health, farming, education, smart cities and transport.
Why it mattered. It set out India's first national plan for using AI for everyone, not just for big companies.
For the cockpit scenes of First Man, the team built an LED screen about 35 feet tall and 60 feet across (about 11 × 18 m) and played about 90 minutes of space and sky footage made by DNEG. Ryan Gosling's visor and eyes reflected it for real. The film won the Oscar for visual effects.
Why it mattered. It showed LED screens could replace green screen for whole sequences, reflections included.
Nvidia announced its Turing chips with RT cores, parts built just to test rays against triangles. Nvidia claimed up to 10 gigarays a second, and said a GeForce RTX 2080 Ti was roughly nine or ten times faster at ray tracing than the older GTX 1080 Ti. GeForce RTX cards reached gamers in September 2018.
Why it mattered. Ray tracing moved from render farms into ordinary home computers.
Sony Pictures Animation and Sony Pictures ImageworksCulver City, California, and Vancouver, Canada
Spider-Man: Into the Spider-Verse used 3D models and rigs but rendered them to look like a printed comic, with hand-drawn lines, halftone dots and characters animated on twos. It won the Oscar for Best Animated Feature.
Why it mattered. It showed 3D animation does not have to look realistic, and inspired many stylised films.
The British cinematographer won his first Oscar for Blade Runner 2049 at the 2018 ceremony, on his 14th nomination, and his second for 1917 in 2020. On Blade Runner 2049 his team hung 100 SkyPanels in one ceiling and ran 256 small Fresnels in circles to make moving sunlight. Every light was meant to seem to come from a real source in the scene.
Why it mattered. Deakins is a leading example of motivated lighting, where every light has a reason to be there.
The first woman nominated for the cinematography Oscar
Rachel MorrisonHollywood, USA
In 90 years of Academy Awards, no woman had ever been nominated for Best Cinematography. Rachel Morrison broke that record with Mudbound (2017). Camera departments are still mostly men, but that is slowly changing.
Why it mattered. Who holds the camera shapes how the world is seen on screen.
Justin K. Thompson and Sony Pictures AnimationLos Angeles, USA
For Spider-Man: Into the Spider-Verse, the team drew and painted comic-book lines, dots and textures on top of 3D frames. Production designer Justin K. Thompson helped set the style. It won the Oscar for best animated film.
Why it mattered. Visual development can invent a brand new look for a whole kind of film.
Poor food makes TB more likely and harder to beat. Under the Nikshay Poshan Yojana, every notified TB patient in India gets money for food each month while on treatment, first ₹500 and, from November 2024, ₹1,000. It is paid straight into their bank accounts.
Why it mattered. It treats hunger as part of treating the lungs.
On World Hepatitis Day, India launched the National Viral Hepatitis Control Programme. It offers free testing and treatment for hepatitis B and C through a network of hospitals and clinics across the country.
Why it mattered. It puts hepatitis C cures within reach of millions of Indians.
Emily Liman's lab; Charles Zuker's labLos Angeles and New York, USA
Sour was the last basic taste without a known receptor. In 2018 Liman's team showed that OTOP1, a channel that lets protons in, is found in sour cells. In 2019 her lab and Zuker's showed that mice without it barely sense sour.
Why it mattered. It completed the set: each of the five tastes now has a known sensor.
The government declared every inhabited village in India electrified when Leisang in Manipur was connected. A village counted as electrified once its public places and at least 10% of its homes had power; connecting every household took longer.
Why it mattered. A milestone 139 years after Calcutta's first electric light.
Ather Energy (Tarun Mehta and Swapnil Jain)Bengaluru, India
A Bengaluru start-up launched a fast electric scooter with a touchscreen and its own charging network. It uses about 25–30 Wh of electricity per kilometre.
Why it mattered. It showed that electric scooters could be desirable, not just cheap.
Bart Weber, Daniel Bonn, Mischa Bonn and colleaguesAmsterdam, Netherlands, and Mainz, Germany
Measuring steel sliding on ice from −100 °C to 0 °C, and probing the surface with lasers, the team found that the top layer of ice molecules is only loosely bound and moves almost freely. Friction was lowest at about −7 °C, the temperature used on speed-skating rinks.
Why it mattered. It showed that ice is slippery mainly because of its own loose surface, not pressure.
Philips; later Siemens HealthineersZurich, Switzerland and worldwide
Helium is scarce and its price swings with shortages. Philips' sealed BlueSeal 1.5 T magnet holds about 7 litres instead of about 1,500, with no quench pipe. In 2021 Siemens' 0.55 T MAGNETOM Free.Max was cleared with less than a litre.
Why it mattered. Low-helium magnets make MRI cheaper to run and easier to install.
Miele's G 7000 range added AutoDos, a built-in cartridge that adds detergent to each wash by itself. The machine can also be controlled from a phone app.
Why it mattered. Too much detergent wastes chemicals and too little leaves dirt, so the machine now measures it for you.
The IEA counted about 1.6 billion air conditioners in use and warned that the number could reach 5.6 billion by 2050. Most people buy units less than half as efficient as the best ones for sale.
Why it mattered. It made cooling efficiency one of the biggest energy questions of the century.
Pedalling in the still air behind a dragster's fairing, Mueller-Korenek averaged 296 km/h over a measured mile, beating Fred Rompelberg's 268.8 km/h from 1995.
Why it mattered. Drafting at its most extreme: the fairing takes the air's ½ρv² so the rider doesn't have to.
Computational photography merges many quick frames into one picture, lining them up and averaging away noise. Night modes can make bright, clean photos in near darkness without a flash.
Why it mattered. Clever maths now does part of the job that big lenses and sensors used to do.
Varun Gulshan and colleagues, with Aravind and Sankara NethralayaMadurai and Chennai, India
A deep-learning system for diabetic retinopathy was tested on 3,049 patients at two Indian eye hospitals. It spotted cases needing a doctor about as well as, or better than, trained graders and eye specialists.
Why it mattered. Screening aids like this could help reach millions of people with diabetes where eye doctors are scarce.
Patrick Grother, Mei Ngan and Kayee HanaokaNIST, Gaithersburg, United States
The US standards agency tested 189 face recognition algorithms. False matches were often 10 to more than 100 times more common for some demographic groups than others, though the size of the gap depended strongly on the algorithm.
Why it mattered. It gave governments and buyers hard numbers on how accurate and how fair different systems are.
Google rolled out an all-neural speech recogniser that runs entirely on Pixel phones. Quantisation shrank it from 450 MB to 80 MB and made it about four times faster.
Why it mattered. Voice typing could work offline and privately, with no round trip to a server.
GPT-2, with 1.5 billion parameters, wrote fluent paragraphs from a one-line prompt. OpenAI first released only smaller versions, citing possible misuse, and published the full model in November 2019.
Why it mattered. It started the public debate about what fluent machine text could be used for.
Geoffrey Hinton, Yann LeCun and Yoshua BengioNew York, United States (ACM)
The ACM gave its 2018 Turing Award, often called the Nobel Prize of computing, to three researchers who kept faith in neural networks during the lean years.
Why it mattered. It marked how far neural networks had travelled, from fringe idea to the centre of computer science.
England's NHS was reported to use about 130,000 pagers, around one in ten of those left in the world, at about £6.6 million a year. Hospitals were told to phase them out by the end of 2021, keeping some for emergencies such as a Wi-Fi failure.
Why it mattered. Even the bleep's birthplace began switching to phone apps.
SK Telecom, KT, LG U+ and VerizonSouth Korea and USA
South Korea's three operators and America's Verizon switched on the first 5G phone networks within hours of each other. 5G adds wider channels, beam-steering antennas and millimetre-wave bands.
Why it mattered. Faster, lower-delay links, and wireless broadband for homes.
Gemini Man was shot at 120 frames a second in 3D and shown at that speed on a few specially equipped screens. That is five times the usual 24. Most cinemas showed slower versions, because few projectors could keep up.
Why it mattered. It tested how far digital projection could push smooth motion, and showed that audiences do not all want it.
Jon Favreau, Magnopus and Unity TechnologiesLos Angeles, USA
The Lion King's crew walked around its computer-made African landscapes wearing VR headsets, placing virtual cameras and lights as on a real location. The platform was built on the Unity game engine.
Why it mattered. Game engines had become film tools, and crews learned to 'shoot' inside them.
Epic Games with Lux Machina, Magnopus, Profile Studios, Quixel, ARRI and DP Matt WorkmanSIGGRAPH, Los Angeles, USA
At the SIGGRAPH conference, Epic showed a small LED volume of three walls and a ceiling, run by Unreal Engine's nDisplay. A tracked camera filmed a motorcyclist in a virtual desert, with the walls lighting and reflecting on him, final pixel in camera.
Why it mattered. It showed the rest of the industry the whole in-camera VFX workflow working live.
ILM, Jon Favreau, Greig Fraser, Epic Games and partnersManhattan Beach Studios, California, USA
The first season of The Mandalorian was filmed in an LED volume about 6 m (20 ft) tall and 23 m (75 ft) across, wrapping 270° with an LED ceiling: 1,326 ROE Black Pearl panels at 2.84 mm pitch, run by Unreal Engine. More than half the season was shot this way, with about 8 frames of latency and 40% overscan.
Why it mattered. It made LED volumes famous and set the pattern that most stages still follow.
Dan DeLeeuw and many studios, for Avengers: EndgameStudios in several countries
Avengers: Endgame had 2,496 visual effects shots. The team finished with only about two and a half weeks to spare before release. Studios including ILM and Weta Digital shared the work.
Why it mattered. It shows that in a modern blockbuster, nearly every shot has been touched by effects artists.
ILM and Jon Favreau, for The MandalorianManhattan Beach, California, USA
ILM built StageCraft, a curved wall of LED screens about 20 feet tall that wraps 270 degrees around the actors. A game engine draws the background live and moves it to match the camera. See VirtualProdClear for how it works.
Why it mattered. Actors can see the world they are in, and the light from the screens falls on them naturally, with no green spill.
ILM (StageCraft) with Epic GamesLos Angeles area, California, USA
For The Mandalorian, ILM surrounded actors with a curved LED wall about 6 m tall and 270 degrees around. Unreal Engine rendered the background live and shifted it as the camera moved, so the scenery looked right through the lens. ILM says over half of season one was filmed this way.
Why it mattered. Real-time rendering moved from games onto film sets, replacing many green screens.
Klaus was drawn by hand, then given soft, volumetric light and texture with new tools, asking how 2D might have grown if studios had not switched to CGI. It won the BAFTA for best animated film.
Why it mattered. It proved hand-drawn features can still look new in the digital age.
Industrial Light & Magic; Epic Games; Greig Fraser and Barry IdoineManhattan Beach, California
The Mandalorian was filmed inside a ring of 1,326 LED screens, 20 feet high and wrapping 270 degrees, with an LED ceiling above. A game engine drew the background in real time. The screens also lit the actors, and their glow showed up as real reflections on the hero's shiny armour.
Why it mattered. The background became a light source, so the lighting of the set and the world could finally match.
Industrial Light & Magic and Jon FavreauManhattan Beach, California, USA
For The Mandalorian, ILM surrounded actors with a curved wall of LED screens showing 3D worlds drawn in real time by a game engine. The background shifts as the camera moves, so it looks real on camera. More than half of season one was filmed this way.
Why it mattered. The digital world built during planning could now appear on the set itself.
The Mandalorian was filmed inside a ring of LED screens showing computer-made landscapes that moved with the camera. Actors could see the world around them, and the screens also lit the scene.
Why it mattered. Virtual production brings visual effects onto the set, during the shoot.
Joy Milne, Perdita Barran and colleaguesManchester, UK
Joy Milne, a retired nurse, noticed a musky smell on her husband years before he was diagnosed with Parkinson’s disease. Scientists used her nose to find molecules in skin oil (sebum) that differ in people with Parkinson’s.
Why it mattered. One unusual nose pointed chemists towards a possible simple test for a disease.
The WHO and the International Telecommunication Union set out how phones and music players should track your weekly sound dose, with a reference of 80 dB for 40 hours a week for adults, and warn you before it runs out.
Why it mattered. It turns the science of noise damage into a feature in your pocket.
The first WHO World report on vision estimated that at least 2.2 billion people have a near or distance vision problem, and that at least 1 billion of these could have been prevented or have not been treated.
Why it mattered. It showed that most poor sight is caused by things we already know how to fix, such as cataracts and missing glasses.
The SI units were redefined. The ampere is now set by fixing the charge of one electron at exactly 1.602176634 × 10⁻¹⁹ coulombs, so one amp is about 6.24 × 10¹⁸ electrons a second.
Why it mattered. Current is now defined by counting electrons, just as chapter 1 does.
A 2016 rule came fully into force: every new two-wheeler above 125 cc must have ABS, and smaller ones must have ABS or a combined braking system (CBS), in which the rear lever also brakes the front wheel.
Why it mattered. Two-wheeler riders are among the most at risk on Indian roads, and better brakes save lives.
General Conference on Weights and MeasuresSèvres, France
The kilogram stopped being a metal cylinder in a vault. It is now fixed by the Planck constant, and Kibble balances, renamed after Bryan Kibble in 2016, realise it by balancing mechanical and electrical power.
Why it mattered. A unit of mass now rests on measuring watts.
National Council on Radiation Protection and Measurements (NCRP)Bethesda, Maryland, USA
An earlier NCRP report found that Americans got about six times more medical radiation in 2006 than in the early 1980s, mostly from CT. Its 2019 report found the average had fallen between 2006 and 2016. Campaigns to use lower doses and smarter scanners were working.
Why it mattered. It showed that more imaging does not have to mean more radiation.
General Conference on Weights and MeasuresVersailles and Sèvres, France
After a vote in November 2018, the kilogram stopped being the mass of a metal cylinder. It is now fixed by the Planck constant, h = 6.626 070 15 × 10⁻³⁴ J·s, and realised with instruments such as the Kibble balance, proposed by Bryan Kibble in 1975.
Why it mattered. Anyone, anywhere, can now make a kilogram from a constant of nature.
BIPM and national labs, using Bryan Kibble's balanceWorldwide
Since 1889 the kilogram had been a metal cylinder kept near Paris. From 2019 it is defined by a fixed number of nature, the Planck constant. A Kibble balance, invented by Bryan Kibble in 1975, balances a weight against an electromagnetic force to realise it.
Why it mattered. Because a newton is a kilogram times a metre per second squared, the newton now rests on constants of nature too.
Government of India and the Bureau of Indian StandardsIndia
Under the Kitchen Appliances (Quality Control) Order, 2018, food mixers, hand blenders and juicers sold in India had to carry the ISI mark from 1 May 2019. Mixers must pass the tests of IS 4250, including the checks for electric shock, overheating and moving parts.
Why it mattered. Unsafe or badly made mixers could no longer be sold legally, even if they were cheap.
By about 2019 some 16,000 desalination plants were running around the world, making roughly 95 million cubic metres of fresh water a day, most of it by reverse osmosis. Seawater plants push at 40–80 bar to beat the sea's osmotic pressure.
Why it mattered. The pig's bladder effect, run backwards, now waters cities.
India's National Green Tribunal told the government to stop RO use where water already has less than 500 mg per litre of TDS. It asked that purifiers recover more than 60% of the water, aiming for 75%, and that the reject water be used for mopping, gardening or washing. A 2020 draft rule, later tribunal orders and a 2022 Supreme Court stay kept the debate going.
Why it mattered. It made the whole country ask how much water home purifiers throw away, and whether soft water really needs RO.
Edward Jones and colleagues (UN University)Worldwide
A study counted 15,906 working desalination plants making about 95 million cubic metres of fresh water a day, almost half of it in the Middle East and North Africa. It also found they make about 142 million cubic metres of salty brine a day.
Why it mattered. It showed that the waste stream, not just the clean water, is a big part of the desalination story.
John Goodenough, M. Stanley Whittingham and Akira YoshinoStockholm, Sweden
The three scientists shared the Nobel Prize in Chemistry for developing the lithium-ion battery. Goodenough was 97, the oldest person ever to win a Nobel Prize.
Why it mattered. The prize honoured a battery that now powers phones, cars and home backup.
General Conference on Weights and Measures (CGPM)Versailles, France (vote in November 2018)
The world's measurement scientists fixed the Boltzmann constant and the Avogadro constant at exact values. Since R is simply one times the other, the gas constant became exact too: 8.31446261815324 joules per mole per kelvin. The kelvin itself is now defined through the Boltzmann constant.
Why it mattered. The constant in PV = nRT is now a fixed part of how the world defines temperature and amount.
Event Horizon Telescope collaborationRadio telescopes around the world
Radio dishes on several continents worked together as one virtual telescope the size of the Earth to image the shadow of the black hole at the centre of the galaxy M87.
Why it mattered. Still the same idea as Mozi's hole in the wall: collect light (here, radio waves) and rebuild an image.
General Conference on Weights and MeasuresSèvres (Paris)
The SI was redefined so that Planck's constant h and the electron's charge e have exact values. That makes the von Klitzing constant h/e² exact too, so the ohm is now defined by constants of nature.
Why it mattered. Two centuries after a schoolteacher's wires, the ohm is built into the definition of all units.
Tamil Nadu gave out Kabasura kudineer and Nilavembu kudineer in COVID-19 containment zones under its Arogyam scheme, stating clearly that they were not a cure.
Why it mattered. It led to the first randomised trials of Siddha decoctions.
The National Commission for Indian System of Medicine Act replaced the 1970 Act. NCISM took over from the Central Council of Indian Medicine in June 2021 and now regulates Siddha education and practice.
Why it mattered. It is the body Siddha doctors register with today.
The National Medical Commission replaced the Medical Council of India as the regulator of medical education and doctors. It oversees the MBBS course, the NEET entrance exam system for medical colleges and the rules doctors practise by.
Why it mattered. India now has over 800 medical colleges and more than 1.2 lakh MBBS seats a year.
The National Commission for Indian System of Medicine Act replaced the old council with the NCISM, which regulates Unani, Ayurveda, Siddha and Sowa-Rigpa education and practice.
Why it mattered. It sets the standards for today’s hakims.
A new law replaced the Central Council with the National Commission for Homoeopathy, which came into force on 5 July 2021. It regulates homeopathy colleges and the register of practitioners.
Why it mattered. India now has more than 3.45 lakh registered homeopathy practitioners.
The National Commission for Indian System of Medicine Act replaced the Central Council of Indian Medicine with a new regulator for education and practice, including a national exit test for new graduates.
Why it mattered. It modernised how Ayurvedic doctors are trained and registered.
Jonathan Ho, Ajay Jain and Pieter AbbeelUC Berkeley, United States
Denoising diffusion probabilistic models (DDPM) trained a network to predict the noise hidden in a picture, then removed it step by step, starting from pure static. The images matched the best GANs, and training was much more stable.
Why it mattered. Almost every image and video generator since is built on this recipe.
Alexey Dosovitskiy and colleaguesGoogle Research, Berlin, Germany
The paper 'An Image is Worth 16x16 Words' cut pictures into patches and fed them to a transformer, the design behind language models. With enough training data, it matched or beat the best CNNs.
Why it mattered. Vision and language models began to share one design.
Tom Brown and colleagues at OpenAISan Francisco, United States
GPT-3 had 175 billion parameters and was trained on about 300 billion tokens. Given a few examples in the prompt, it could do new tasks with no extra training. The same year, OpenAI researchers reported smooth "scaling laws" for size, data and compute.
Why it mattered. Scale itself became the strategy, and so did its cost in chips and energy.
John Jumper, Demis Hassabis and the DeepMind teamLondon, United Kingdom
At the CASP14 contest, DeepMind's AlphaFold 2 predicted the 3D shapes of proteins with accuracy close to lab experiments for many targets. Protein shapes decide how medicines and diseases work.
Why it mattered. It showed neural networks helping with a real science problem, and later won a share of the 2024 Nobel Prize in Chemistry.
C-DAC and the National Supercomputing MissionPune and across India
PARAM Siddhi-AI ranked 63rd in the world in November 2020, at about 4.6 petaflops. In 2023 the AIRAWAT system at C-DAC ranked 75th. By August 2025 the National Supercomputing Mission, begun in 2015, had installed 37 supercomputers with about 40 petaflops in total.
Why it mattered. India now builds and runs supercomputers for weather, medicine and AI research.
When the pandemic stopped travel, filming a far-off place without going there became very attractive. Most LED stages were built during or after the lockdowns. Epic Games estimated there were about 300 by October 2022, up from 3 in 2019.
Why it mattered. Virtual production went from one famous show to a normal tool, within three years.
A study compared OpenPose with several video cameras against a marker system. About 80% of joint errors were under 30 mm, but some were over 40 mm. Markers still win when millimetres matter.
Why it mattered. It measured the trade-off: markerless is easy and cheap, optical is precise.
Christopher Nolan; Scott R. FisherVictorville, California
For Tenet, the film-makers found that buying a real Boeing 747 was cheaper than building models and adding visual effects. The plane was rolled into a building at an airport, under tight control. Special effects supervisor Scott Fisher oversaw the scene.
Why it mattered. Sometimes the real thing is both cheaper and more convincing than faking it.
With cinemas shut by the COVID-19 pandemic, the Hindi film Gulabo Sitabo, starring Amitabh Bachchan, premiered directly on a streaming service. It was among the first big Indian films to skip cinemas.
Why it mattered. Streaming became a major way Indian films reach their audience and earn money.
Less than a year after the new coronavirus was identified, 90-year-old Margaret Keenan became the first person to receive an approved COVID-19 vaccine outside a trial. Vaccines made in several ways followed within weeks.
Why it mattered. It was the fastest vaccine development in history, built on decades of earlier work.
Harvey Alter, Michael Houghton and Charles RiceStockholm, Sweden
The Nobel Prize in Physiology or Medicine went to three scientists for discovering hepatitis C virus. Alter showed an unknown virus existed, Houghton found its genes, and Rice proved the virus alone causes the disease.
Why it mattered. It honoured a discovery that led to blood tests and cures that have saved millions of lives.
During the COVID-19 pandemic, sudden loss of smell, and with it much of the sense of taste, became one of the best-known symptoms. Health services such as the UK's NHS and the US CDC added it to their symptom lists in 2020.
Why it mattered. Millions of people learned how much of flavour depends on smell, and research into smell loss grew fast.
In March 2020, ear, nose and throat doctors warned that sudden loss of smell could be a sign of COVID-19. On 18 May 2020 the UK added it to the official symptom list. Early studies found smell loss in roughly 40 to 50% of patients, far fewer with the later Omicron variant.
Why it mattered. Millions of people discovered how much they rely on a sense they had never thought about.
David Brann, Sandeep Robert Datta and colleaguesHarvard Medical School, USA
Researchers found that the proteins the virus uses to enter cells are made by the supporting cells of the smell patch, not by the smell neurons themselves. Damage to these helper cells disrupts smell.
Why it mattered. It explained why most people recover: the neurons are mostly spared and the support cells regrow.
India jumped straight from BS-IV to BS-VI emission rules. To meet them, almost every new motorcycle switched from a carburettor to electronic fuel injection and a catalytic converter.
Why it mattered. Cleaner air in crowded cities, and the end of the carburettor on new Indian bikes.
The US FDA cleared the first portable MRI scanner, which runs on a 0.064 T permanent magnet and a normal power socket and can be wheeled to a patient's bedside.
Why it mattered. Low-field scanners could bring MRI to places that cannot house a giant magnet.
Home cooks in the United States and beyondUnited States
During the COVID-19 pandemic, people stayed home and cooked more. The market researcher NPD counted 25.6 million air fryers sold in the US from January 2020 to December 2021, 76% more than in the two years before. About 36% of US households owned one in 2020.
Why it mattered. The air fryer went from a curious gadget to an everyday appliance.
BARC India estimated that 210 million Indian households owned a TV, up from 197 million in 2018. That meant about 892 million people could watch. Around 90 million homes still did not have one.
Why it mattered. Even in the age of phones, television is still growing in India.
Very few Indian homes owned a dishwasher, and many relied on paid help to wash up. When the COVID-19 lockdown kept helpers away, The News Minute reported LG seeing a 400–500% surge in demand. A Bosch-Siemens executive later told afaqs! that yearly sales rose from 50,000–60,000 units before COVID to about 1.5 lakh (150,000) during it.
Why it mattered. A crisis made millions of people think again about who washes the dishes.
In a double-blind trial of 120 COVID-19 patients on standard care, those given Nilavembu or Kabasura kudineer left hospital sooner than those given a placebo drink. Larger, independent trials are still needed.
Why it mattered. It shows Siddha remedies can be tested fairly, and that one small trial is only a start.
Serum Institute of India (Covishield) and Bharat Biotech with ICMR (Covaxin)Pune and Hyderabad
India began vaccinating against COVID-19 with Covishield, the Oxford–AstraZeneca vaccine made by the Serum Institute in Pune, and Covaxin, an inactivated vaccine developed by Bharat Biotech with ICMR’s National Institute of Virology. Both had been tested in large trials, and more than 200 crore doses were given within about 18 months.
Why it mattered. Vaccines were designed, tested in fair trials and given to billions within about two years of a new virus appearing.
Adobe, Arm, BBC, Intel, Microsoft and TruepicUnited States and United Kingdom
Six organisations formed the Coalition for Content Provenance and Authenticity (C2PA) to write an open standard for "content credentials": signed records, attached to a file, of who made it and how it was edited. Many AI tools later used it to mark their output.
Why it mattered. It gave the world a shared way to say where a picture or video came from.
Robin Rombach, Andreas Blattmann, Dominik Lorenz, Patrick Esser and Björn OmmerLMU Munich and Heidelberg University, Germany
Instead of denoising every pixel, latent diffusion first squeezes an image with an autoencoder into a much smaller grid of numbers, the "latent". Diffusion happens there, and a decoder turns the result back into pixels. This cut the cost dramatically.
Why it mattered. Video models compress in the same way, in both space and time, or they could never afford to run.
Classifier-free guidance trains one model both with and without the text prompt. At each step it pushes the picture further in the direction the prompt suggests. First shown at a NeurIPS workshop, it was posted on arXiv in July 2022.
Why it mattered. It is the "follow the prompt more closely" dial inside nearly every text-to-image and text-to-video model.
Alec Radford and colleaguesOpenAI, San Francisco, United States
CLIP learned from about 400 million pictures with captions from the web, matching each picture with its text. It could then recognise things it was never given labels for, just from a written description.
Why it mattered. It led to vision-language models that caption photos and answer questions about them.
Emily M. Bender, Timnit Gebru, Angelina McMillan-Major and Margaret MitchellFAccT conference
This paper argued that ever-bigger language models carry costs: energy use, biased and hard-to-audit training data, and fluent text that people may wrongly trust. Its publication became part of a public dispute at Google.
Why it mattered. It put bias, energy and over-trust at the centre of the debate.
Taro Kono, Japan's administrative reform ministerTokyo, Japan
Japan's government asked ministries to stop using fax. It met strong resistance, with ministries raising hundreds of objections about security and practicality.
Why it mattered. Fax still survives in some offices because it is simple, familiar and trusted.
Industrial Light & MagicPinewood Studios, England, UK
ILM opened a permanent StageCraft volume at Pinewood Studios near London, after a second one in Manhattan Beach, and announced another in Vancouver later that year.
Why it mattered. The idea spread from one stage in California to permanent stages on several continents.
Bharat Biotech with ICMR and the National Institute of VirologyHyderabad and Pune
On 3 January 2021 India’s drug regulator approved Covaxin, a killed-virus vaccine made in India, and Covishield, made by the Serum Institute of India, for emergency use. India’s vaccination drive began on 16 January 2021 and gave more than two billion doses.
Why it mattered. India made and gave vaccines on a scale few countries could match.
WHO halved its guideline for fine PM2.5 dust to a yearly average of 5 micrograms per cubic metre. These tiny particles slip past the nose and deep into the air sacs. India's own national limit, set in 2009, is 40, and cities such as Delhi are often far above even that.
Why it mattered. Clean air is one of the biggest things that keeps lungs healthy for life.
David Julius and Ardem PatapoutianStockholm, Sweden
The Nobel Prize in Physiology or Medicine went to Julius, for finding TRPV1 with capsaicin, and to Patapoutian, for finding the touch sensors PIEZO1 and PIEZO2. Both also found TRPM8, the cold sensor.
Why it mattered. The science behind chilli heat and minty cool reached the top of medicine.
David Julius and Ardem PatapoutianStockholm, Sweden
David Julius shared the Nobel Prize for discovering TRPV1, the sensor that capsaicin in chilli triggers, and, with others, the menthol sensor TRPM8. These sit on the trigeminal nerve endings in the mouth and nose.
Why it mattered. It explains why chilli burns and mint cools, even though neither is a taste or a smell.
The WHO reported that about 1.5 billion people live with some hearing loss, and that nearly 2.5 billion may by 2050, unless more is done. Much of it could be prevented, for example by safe listening and treating ear infections.
Why it mattered. It made hearing a global health priority, not a private problem.
Pooling Indian studies, researchers found that myopia in city children aged 5 to 15 rose from about 4% in 1999 to about 21% in 2019, and projected about 48% by 2050.
Why it mattered. Short sight is becoming one of the most common health problems for Indian children.
Hospitals, oxygen makers and railways across IndiaIndia
In the COVID-19 second wave, sick lungs could not take in enough oxygen, and hospitals ran short. The government told Parliament that daily demand for medical oxygen peaked at nearly 9,000 tonnes, about three times the first wave’s peak. Special Oxygen Express trains and air force planes rushed oxygen tankers across the country.
Why it mattered. It showed a whole country how vital the oxygen in every breath is.
WHO halved its guideline for fine PM2.5 dust to a yearly average of 5 micrograms per cubic metre, with a 24-hour limit of 15. These tiny particles slip deep into the air sacs. Most cities in India are many times above the new limit.
Why it mattered. Clean air is one of the biggest things that keeps lungs healthy for life.
Ola Electric launched its S1 scooters, built at a huge new factory in Tamil Nadu. Electric scooters from many makers quickly became a common sight in Indian cities.
Why it mattered. India's two-wheelers began to switch from petrol to batteries.
Siemens HealthineersErlangen, Germany; cleared in the USA
The US FDA cleared the NAEOTOM Alpha, the first photon-counting CT scanner. Its cadmium telluride detectors turn each X-ray straight into an electrical pulse and sort it by energy, instead of adding up flashes of light.
Why it mattered. It is the biggest change to CT detectors since the 1970s.
India's National Family Health Survey for 2019–21 found that 37.9% of households owned a fridge: 63.4% in towns and cities but only 25.2% in villages. In 1998–99 the figure had been about 11%.
Why it mattered. Hundreds of millions of families still keep food without a fridge, so how efficient the next ones are really matters.
So many dishwashers were rated A+++ that the EU brought back a simple A to G label with much stricter classes. By 2020 the average new dishwasher in the EU used about 10 litres of water per cycle, a third of the 1990 amount.
Why it mattered. Resetting the scale left room for machines to keep getting better.
India's biggest household survey found that 18% of households owned a washing machine. In cities the figure was about 36%, but in villages it was only 9%. Most families, and mostly women, still wash clothes by hand.
Why it mattered. The washing machine story is not finished: for billions of people, washing day is still hard work.
WHO estimates that about 2.1 billion people still cook on open fires or simple stoves burning wood, dung, crop waste, coal or kerosene. Smoke from these fires caused about 2.9 million deaths in 2021, including more than 309,000 children under five. Women and children bear most of the harm.
Why it mattered. Getting smoke out of kitchens, with clean fuel and good ventilation, saves lives.
UNEP and governments worldwideAlgeria and worldwide
In 1921 Kettering's team found that adding tetraethyl lead to petrol stopped engines from knocking, and leaded petrol spread around the world. Lead is a poison, especially for children's brains. After a 19-year UN campaign, Algeria, the last country selling it, stopped in July 2021.
Why it mattered. The UN estimates the ban prevents more than 1.2 million early deaths a year.
Cochrane review (Wieland and colleagues)International
A review of 21 trials with 2,223 people, several of them run in India, found yoga gave a small improvement in back pain compared with no exercise, and about the same as other back exercises.
Why it mattered. A fair look at one of the best-studied parts of yoga and naturopathy.
The World Health Organization and India agreed to set up the WHO Global Centre for Traditional Medicine, backed by US$250 million from India, to study traditional medicine from around the world with modern science.
Why it mattered. The first global WHO centre for traditional medicine puts evidence and safety at its heart.
Jonathan Ho, Tim Salimans, Alexey Gritsenko, William Chan, Mohammad Norouzi and David FleetGoogle, United States
Video Diffusion Models denoised all the frames of a short clip together, so each frame could "see" its neighbours. This kept objects steadier from frame to frame than making each frame separately.
Why it mattered. Denoising frames together is the main trick for keeping video consistent.
Stability AI, CompVis at LMU Munich and RunwayMunich, Germany and London, United Kingdom
A latent diffusion model trained on billions of captioned images was released with its weights, so anyone with a gaming graphics card could run it at home. Thousands of tools and many later open video models were built on it.
Why it mattered. Image generation went from lab demo to something millions of people could use and study.
Uriel Singer, Adam Polyak, Devi Parikh, Yaniv Taigman and colleagues at Meta AITel Aviv, Israel and Menlo Park, United States
Meta's team took a text-to-image model and taught it motion from videos that had no captions at all. It produced short, low-resolution clips from a sentence.
Why it mattered. It showed video models could borrow what image models already knew about the world.
Jonathan Ho, William Chan, Chitwan Saharia and colleagues at GoogleMountain View, United States
A chain of seven diffusion models first made a small, jerky clip, then filled in extra frames and added detail. The paper reports 128 frames at 1280 by 768 pixels and 24 frames per second, about 5.3 seconds.
Why it mattered. It reached HD resolution by building a clip up in stages.
William Peebles and Saining XieUC Berkeley and New York University, United States
The diffusion transformer (DiT) cut the latent into small patches and processed them with a transformer, the same design behind chatbots. Bigger transformers gave better pictures, predictably.
Why it mattered. This design, scaled up to patches of space and time, became the backbone of Sora and many later video models.
Ministry of Civil Aviation and the Digi Yatra FoundationDelhi, Bengaluru and Varanasi airports, India
India launched DigiYatra, which lets passengers who sign up walk through airport gates by face instead of showing papers. The government says it is voluntary and privacy-focused; digital-rights groups have raised concerns about consent, data sharing and transparency.
Why it mattered. It shows both the convenience of face recognition and why clear rules on consent and data matter.
Tri Dao, Daniel Fu, Stefano Ermon, Atri Rudra and Christopher RéStanford University, United States
FlashAttention computed attention in small tiles that stay in the GPU's fast on-chip memory, instead of writing big tables out to slower memory. The answers are exactly the same, only faster.
Why it mattered. It showed that for AI chips, moving data costs more than doing the maths.
Gyeong-In Yu, Joo Seong Jeong and colleaguesSeoul National University and FriendliAI, South Korea
Orca let a server add new requests to a running batch after every token, instead of waiting for the whole batch to finish. Short and long answers no longer held each other up.
Why it mattered. Almost every LLM server now batches this way, sharing each read of the weights across many users.
Tim Dettmers and colleagues (LLM.int8()); Elias Frantar and colleagues (GPTQ)University of Washington, United States; IST Austria
LLM.int8() ran models with 175 billion parameters in 8-bit with no loss in quality. Weeks later GPTQ showed weights could go down to 3 or 4 bits with small losses.
Why it mattered. Huge models could suddenly fit on far fewer GPUs, and smaller ones on laptops.
Government of India (Ministry of Electronics and IT)Gandhinagar, India
The Prime Minister launched Digital India Bhashini at Digital India Week 2022, a platform for translation and speech tools in Indian languages, open to apps and services.
Why it mattered. Serving AI in many languages, cheaply and at scale, became national infrastructure.
Long Ouyang and colleagues at OpenAI; DeepMind's Chinchilla teamSan Francisco and London
InstructGPT used human-written examples and RLHF to make GPT-3 follow instructions; people preferred a 1.3-billion-parameter tuned model to the raw 175-billion one. The same month, DeepMind's Chinchilla showed models needed far more training text, about 20 tokens per parameter.
Why it mattered. Teaching and data, not only size, turned out to matter.
OpenAI released ChatGPT as a free research preview. It passed a million users within about five days, and was reported to reach 100 million monthly users by January 2023, one of the fastest-growing apps ever (an analyst estimate).
Why it mattered. LLMs went from research papers to everyday tools for students, workers and families.
Ministry of Electronics and IT, Government of IndiaGandhinagar, India
The Prime Minister launched Digital India Bhashini during Digital India Week. It aims to build AI tools for translation and speech in Indian languages, using datasets that citizens can help create through BhashaDaan.
Why it mattered. Neural networks learn from data, so a country with many languages needs data in all of them.
Government of India, Jio and AirtelNew Delhi, India
Prime Minister Narendra Modi launched 5G at the India Mobile Congress. It spread unusually fast: Ookla found India's median mobile download speed rose from about 14 Mbit/s in September 2022 to about 50 Mbit/s in August 2023.
Why it mattered. One of the fastest 5G rollouts anywhere, using the 3.5 GHz and 700 MHz bands.
Prasad has won National Awards for editing many times since 1989 and has cut films in 17 languages, from Dil Chahta Hai and Kannathil Muthamittal to RRR (2022).
Why it mattered. His career shows how one editor can shape films across India's many languages.
Epic released Unreal Engine 5, with Nanite for huge amounts of detail and Lumen for light that bounces in real time. Both help virtual worlds look real enough to be filmed directly.
Why it mattered. Better real-time pictures mean more shots can be final straight out of the camera (see CGIClear).
Annapurna Studios and Qube CinemaHyderabad, Telangana, India
Annapurna Studios and Qube Cinema announced an LED virtual production stage in Hyderabad, with a curved wall about 60 ft wide and 20 ft tall (18 × 6 m) of 2.3 mm LEDs, camera tracking and Unreal Engine. Tests began in October 2022 and it has since been used for films, ads and music videos.
Why it mattered. Indian productions could now shoot in-camera VFX at home; other stages, for example in Mumbai, have followed.
LED volumes were used for films such as The Batman and series such as House of the Dragon and 1899, often for night streets, skies, cockpits and far-off landscapes.
Why it mattered. The volume became one tool among many, used where it works best.
James Cameron, Lightstorm and Wētā FXManhattan Beach Studios, California, USA
For Avatar: The Way of Water, the team captured actors underwater in a huge tank built at Manhattan Beach Studios (reports of its size vary). Air bubbles act as tiny wiggling mirrors that fool the cameras, so actors and crew held their breath while performing.
Why it mattered. Capture moved into places once thought impossible for optical systems.
V. Srinivas Mohan and 18 studios, for RRRHyderabad, India, and studios worldwide
RRR had about 2,800 effects shots from 18 studios, finished in around seven months. Many are hidden in plain sight. For the famous animal attack, actors fought around remote-controlled vehicles that were later replaced by digital tigers, bears, wolves and deer.
Why it mattered. The best effects are often the ones nobody spots, and Srinivas Mohan won another National Film Award for special effects.
Unreal Engine 5 was released with Lumen, a system for global illumination and reflections that updates as lights and objects move. It can use ray-tracing hardware or software tricks. Bounced light, once a film-only luxury, became a standard feature of a widely used game engine.
Why it mattered. It put film-style bounced light in the hands of small game and film teams.
V. Srinivas Mohan (VFX supervisor), Makuta VFX and many other studiosHyderabad, India, and studios worldwide
S. S. Rajamouli's RRR used visual effects from many studios, led by supervisor V. Srinivas Mohan. Makuta VFX, with a branch in Hyderabad, said it made around 740 shots, the most of any studio on the film. Makuta also worked on the Baahubali films.
Why it mattered. Indian blockbusters now use the same rendering methods as Hollywood, often made by Indian artists.
Super Giant Robot Brothers was made entirely inside Unreal Engine, a video game engine. Animators saw finished-looking frames instantly instead of waiting hours for a render farm.
Why it mattered. Game engines began to change how animation is made.
Sabu Cyril was production designer on RRR. His team built a big village set and a copy of old Delhi at Ramoji Film City. The film became a worldwide hit, and its song Naatu Naatu won an Oscar.
Why it mattered. Careful design of a past world helped an Indian film reach audiences everywhere.
Ellis Monk, with GoogleHarvard University and Google, USA
Harvard sociologist Ellis Monk designed a scale of 10 skin tones, and Google released it openly in May 2022. It is used to check whether cameras, search and computer vision work fairly for people of every skin tone. It covers deep skin tones better than the older Fitzpatrick scale.
Why it mattered. Tools built for everyone should be tested on everyone's skin.
Bartley Griffith and Muhammad MohiuddinUniversity of Maryland Medical Center, Baltimore, USA
David Bennett, 57, was too ill for a normal transplant. Surgeons gave him the heart of a pig whose genes had been changed so the human body would be less likely to reject it. He lived about two months.
Why it mattered. Animal hearts might one day ease the shortage of human donor hearts.
Akal Takht Jathedar Giani Harpreet Singh; the SGPCAmritsar, Punjab, India
The Akal Takht asked the SGPC, which runs the Golden Temple, to bring back traditional string instruments in kirtan within three years, calling the harmonium colonial. The SGPC said it would revive the strings step by step at the Golden Temple, but had no plans to throw out the harmonium. The debate about this imported instrument is still alive.
Why it mattered. More than 140 years after Dwarkin, people still argue about whether the harmonium truly belongs.
As energy bills soared, the market researcher GfK found UK air fryer sales in September 2022 were up 286% on a year before. A small box heats up faster and uses less electricity than a big oven for small meals. A survey that September found about 30% of UK households owned one.
Why it mattered. Saving energy became a new reason to own an air fryer, on top of using less oil.
CNES, ONERA and partnersLaunched from Kourou, French Guiana
The MICROSCOPE satellite (2016–2018) kept titanium and platinum test masses floating inside each other as they fell round the Earth. Its final result found no difference in how they fall: η = (−1.5 ± 2.7) × 10⁻¹⁵.
Why it mattered. It is the most precise test yet that inertial and gravitational mass are the same.
In February 2022 Atomberg launched a mixer grinder with a brushless (BLDC) motor, which it called India's first mixer grinder with an inverter motor, with speeds from about 2,000 to 20,000 turns a minute. In March 2022 Crompton bought a controlling stake in Butterfly.
Why it mattered. The old universal motor, whose carbon brushes wear out, finally has a challenger.
After a pilot of 100,000 fans, India's government-backed EESL began offering 5-star BLDC ceiling fans that draw about 28–32 watts, compared with 70–75 watts for an ordinary induction-motor fan. India buys around 40 million ceiling fans a year.
Why it mattered. Swapping the motor can cut a ceiling fan's electricity use by more than half.
Researchers put temperature sensors in a traditional pudam firing. The bottom of the sealed clay pots reached 807 °C and stayed above 600 °C for about an hour.
Why it mattered. Modern measurement is starting to explain what traditional processing actually does.
Runway announced Gen-2, which made short clips of about four seconds from a text prompt or an image. It opened to the public in stages over the following months and was widely described as the first publicly available text-to-video model.
Why it mattered. Artists and students began experimenting with AI video themselves.
SynthID hid a signal inside AI-made images from Google's Imagen model. People cannot see it, but a detector can find it, even after cropping or compression. In May 2024 Google said it would extend SynthID to video made by Veo.
Why it mattered. Watermarks inside the pixels can survive where a visible label is easily cropped off.
Ministry of Electronics and Information Technology (MeitY)New Delhi, India
In November 2023 a deepfake video of a well-known actor spread widely, and ministers called deepfakes a dangerous form of misinformation. In December MeitY advised all platforms to tell users clearly, at sign-up and when they upload, that impersonation and deceptive content are banned under the IT Rules.
Why it mattered. India began treating deepfakes as a problem platforms must actively deal with.
Gerganov released llama.cpp, plain C/C++ code that ran Meta's LLaMA models on an ordinary MacBook using 4-bit weights. Thousands of people began running LLMs on their own computers.
Why it mattered. It made on-device LLM inference practical for anyone, and pushed quantisation into everyday use.
Woosuk Kwon, Zhuohan Li, Ion Stoica and colleaguesUC Berkeley, United States
The team found that LLM servers wasted 60 to 80% of their KV-cache memory. PagedAttention stores the cache in small pages, like an operating system handles memory, so many more users fit on each GPU. They reported 2 to 4 times the throughput of earlier systems.
Why it mattered. Their open-source vLLM became one of the most widely used ways to serve LLMs.
Speculative decoding: guess ahead, check in one go
Yaniv Leviathan, Matan Kalman and Yossi Matias (Google); independently Charlie Chen and colleagues (DeepMind)Google Research, Israel; DeepMind, London
A small, fast model drafts several tokens; the big model checks them all in a single pass and keeps the ones it agrees with. The output is exactly what the big model alone would give, typically 2 to 3 times faster.
Why it mattered. It beats the one-token-at-a-time memory wall without changing the answers.
NPCI, with AI4Bharat at IIT Madras and BhashiniMumbai, India
At the Global Fintech Fest, NPCI launched voice-based UPI payments in Hindi and English, with language models co-developed with AI4Bharat at IIT Madras under Bhashini. UPI itself handled over 20 billion transactions in August 2025.
Why it mattered. A glimpse of AI inference at the scale of a whole country's payments.
Sasha Luccioni, Yacine Jernite and Emma StrubellHugging Face and Carnegie Mellon University
The study measured the energy of 1,000 inferences across many tasks and models. Generating images used far more energy than classifying text, and big general-purpose models used far more than small task-specific ones.
Why it mattered. It put inference, not just training, at the centre of the AI energy debate.
Google put Gemini Nano, a small language model, onto the Pixel 8 Pro to run features like summarising recordings and smart replies on the device. Apple announced its own on-device model, about 3 billion parameters, in June 2024.
Why it mattered. Language models joined the other small models already running inside phones.
In March 2023 OpenAI released GPT-4, without disclosing its size, and Anthropic released Claude; Google launched Bard, followed by Gemini models in December. Companies began competing on reasoning, safety and cost.
Why it mattered. The largest models also became less open about how they were built.
Meta shared LLaMA's weights with researchers; they leaked online within a week. Llama 2 followed in July 2023 under a licence allowing most commercial use, and thousands of tuned versions appeared, including many for Indian languages.
Why it mattered. Anyone with a good computer could now run, study and adapt a capable LLM.
Sarvam AI, Ola Krutrim, AI4Bharat, NPCIBengaluru and Chennai, India
Sarvam AI released OpenHathi, a Hindi model built on Llama 2 with AI4Bharat at IIT Madras, and Ola announced its Krutrim models on 15 December. Earlier, in September, NPCI had announced Hello! UPI voice payments using Hindi and English language models.
Why it mattered. India's many languages, often costly to tokenize, got models built with them in mind.
Fixed telephone lines fell from 20 per 100 people in 2005 to 11 per 100 in 2023, about 861 million lines, as mobiles took over. Many remaining lines now run over fibre rather than copper.
Why it mattered. The landline is fading, but the ideas inside it, from dialling to digital voice, live on in every mobile call.
Cyberpunk 2077 added an Overdrive mode that replaced its separate shadow, reflection and lighting tricks with full path tracing. It needed a powerful graphics card plus AI upscaling to run smoothly. It was released as a technology preview.
Why it mattered. The method films adopted between about 2006 and 2016 started running live in a popular game.
Scott R. Fisher; Andrew Jackson; Christopher NolanNew Mexico
To show the Trinity test in Oppenheimer, the effects team filmed big, carefully controlled fuel explosions at night. They also filmed small experiments with metal particles, balloons and water tanks. Clever camera work made them look vast.
Why it mattered. It showed how scale can be faked with real footage instead of computer images.
Oppenheimer was shot on 65 mm film, much of it with huge IMAX cameras. For its black-and-white scenes, Kodak made 65 mm black-and-white film for the first time. It became a global hit and won the Oscar for Best Cinematography.
Why it mattered. Digital rules, but some filmmakers still choose film for its look, and audiences follow.
M. M. Keeravani and Chandrabose; S. S. RajamouliLos Angeles
“Naatu Naatu” from the Telugu film RRR won the Academy Award for Best Original Song. That same night the Tamil-language The Elephant Whisperers won Best Documentary Short Film.
Why it mattered. It was the first Oscar for a song from an Indian film production, a sign of Indian cinema's worldwide reach.
ICMR-INDIAB study team (R.M. Anjana and colleagues)All states and union territories of India
A huge survey tested more than 113,000 people across India. It found that about 11.4% of adults had diabetes, around 101 million people, and about 136 million more had prediabetes. The results were published in The Lancet Diabetes & Endocrinology.
Why it mattered. It showed that keeping blood sugar in balance is now one of India's biggest health challenges.
US Food and Drug AdministrationSilver Spring, Maryland
The FDA gave accelerated approval to the first gene therapy for Duchenne muscular dystrophy, which delivers a shortened dystrophin gene, at first for some boys aged 4 to 5. In 2025, after deaths in treated patients, the FDA asked for its use to be paused while safety was reviewed.
Why it mattered. A disease once untreatable now has therapies aimed at its cause, though they are still being tested and carry real risks.
Grégoire Courtine, Jocelyne Bloch and teamLausanne
A man paralysed in a cycling accident received implants over his brain and spinal cord that read his intention to move and stimulate the cord below the injury. He could stand and walk with a frame, and some control returned even with the device off.
Why it mattered. It hints that a cut in the cable may one day be bridged.
The WHO's first report on high blood pressure found it affects about 1 in 3 adults, double the number of 1990, and that nearly half do not know. In India, the NFHS-5 survey (2019–21) had found raised blood pressure in about 1 in 4 adults.
Why it mattered. Measuring blood pressure is cheap, and treating it prevents many heart attacks and strokes.
India recorded about 13,400 kidney transplants in 2023, most from living donors, many of them women giving a kidney to a relative. The total of all organ transplants had more than tripled in ten years.
Why it mattered. Yet it is still far fewer than the number of people whose kidneys fail each year.
ICMR-INDIAB study (R. M. Anjana, V. Mohan and colleagues)All of India's states and union territories
Starting in 2008, the ICMR-INDIAB study tested over 100,000 adults across India. Its 2023 national report estimated that 101 million people had diabetes in 2021, about 11.4% of adults, and another 136 million had prediabetes.
Why it mattered. It showed diabetes is one of India's biggest health challenges, far larger than earlier estimates.
Ed Currie, PuckerButt Pepper CompanySouth Carolina, USA
Guinness World Records named Pepper X, bred by the grower of the Carolina Reaper over a decade, the hottest chilli, at an average of 2,693,000 Scoville heat units.
Why it mattered. Chilli breeding keeps pushing a plant's defence chemical to extremes.
Solar Heat Worldwide counted about 560 GWth of solar thermal collectors working at the end of 2023, around 800 million square metres. China has far more than any other country, and India's market grew by 27% that year.
Why it mattered. Solar water heaters quietly supply more heat than most people realise.
ISRO, Vikram lander and Pragyan roverLaunched from Sriharikota, India
After climbing out of Earth's gravity in ever-bigger orbits and being captured by the Moon's, the Vikram lander touched down at 18:04 IST near the lunar south pole. India became the fourth country to soft-land on the Moon, and the first near its south pole.
Why it mattered. Every step of the journey, from parking orbits to the final braking burn, was planned with the law of gravity.
VoxelGrids; SAMEER and AIIMSBengaluru, Chandrapur and Delhi, India
The Bengaluru start-up VoxelGrids unveiled a 1.5 T scanner in 2023 and installed its first clinical system in Chandrapur, Maharashtra, in December 2025. A government project led by SAMEER is building another 1.5 T system for AIIMS Delhi. Both have been called India's first indigenous MRI.
Why it mattered. Home-grown scanners could make MRI far cheaper for Indian hospitals.
Hillhouse Investment and VersuniAmsterdam, Netherlands
Philips sold its home appliance business, including the Airfryer, to the investment firm Hillhouse in 2021 for about 3.7 billion euros. In 2023 the business was renamed Versuni. It still sells air fryers under the Philips name.
Why it mattered. The Airfryer had become part of a business worth billions of euros.
India made energy star labels compulsory for ceiling fans, with makers given until the end of 2022 to clear unlabelled stock and the rules applying from 1 January 2023. Every fan must now reach at least 1 star, and 5-star fans use about half the power of the most common older models.
Why it mattered. With some 500 million ceiling fans in use in India, small savings on each one add up to power stations' worth of electricity.
India's nutrition institute issued 17 guidelines: a plate rich in vegetables, fruit, pulses and whole grains, at most 5 g of added salt a day, little sugar and few ultra-processed foods, and regular exercise.
Why it mattered. Much of it matches nature cure's advice on diet, and it is backed by evidence.
The first all-India survey on AYUSH, of over 1.8 lakh households, found that about 46% of rural and 53% of urban people had used AYUSH to prevent or treat illness in the past year. Ayurveda was the most used.
Why it mattered. It shows how many Indian families rely on these systems, which is why fair tests and safety matter.
OpenAI showed Sora, which it reported could make videos up to one minute long. Its technical report described compressing video into a latent space and cutting it into "spacetime patches" for a diffusion transformer. It was not released to the public at first.
Why it mattered. It showed how far scaling a diffusion transformer on video could go, and set off a race.
Ministry of Electronics and Information Technology (MeitY)New Delhi, India
A 1 March advisory asked platforms to seek government permission before offering untested AI models, and to mark AI-made content that could be used as a deepfake with a permanent unique identifier or metadata. After criticism, a 15 March advisory dropped the permission step but kept the call for labels.
Why it mattered. It was India's first push for AI content labels, a step towards later rules.
Google announced Veo, which it reported could make 1080p videos beyond a minute long. Its videos were to carry SynthID watermarks. Veo 2 followed in December 2024.
Why it mattered. Big labs began shipping watermarking alongside video models.
Kuaishou, a short-video company, launched Kling for testing in China. It reported clips up to two minutes long at 1080p and 30 frames per second. Kling soon opened to users around the world.
Why it mattered. Strong video models were now coming from several countries, not one lab.
OpenAI; TencentSan Francisco, United States and Shenzhen, China
On 9 December OpenAI opened Sora to paying users in some countries, with clips up to 1080p and 20 seconds. The same month Tencent released HunyuanVideo, a 13-billion-parameter model with openly published weights, after Tsinghua University and Zhipu AI's open CogVideoX in August.
Why it mattered. Anyone could now study how a large video model is built, not just use one.
The EU's AI Act became law in 2024. Among other rules, it bans real-time face recognition by police in public places except in narrow cases, such as searching for a victim of kidnapping.
Why it mattered. It is one of the first big laws to draw lines around what computer vision may be used for.
Department of Science and Technology, IIT Bombay; Sarvam AINew Delhi and Bengaluru, India
The government launched BharatGen, a publicly funded effort led by IIT Bombay to build multilingual, multimodal models for Indian languages. In October, Sarvam released Sarvam-1, a 2-billion-parameter model for 10 Indian languages and English. In April 2025 the IndiaAI Mission chose Sarvam to build a national model.
Why it mattered. Public money and startups both began building Indian foundation models.
The world's first broad AI law entered into force, sorting AI uses by risk. Rules for general-purpose models like LLMs apply from August 2025, including transparency about training, with most other rules from August 2026.
Why it mattered. Governments began setting binding rules for how AI is built and used.
DeepSeek-V3 used a mixture of experts: 671 billion parameters in total but only 37 billion used for each token. Its report claimed a much lower training cost than rivals, and its weights were published openly.
Why it mattered. Efficiency, not just size, became a race of its own.
Union Cabinet, Government of IndiaNew Delhi, India
The Union Cabinet approved the IndiaAI Mission with an outlay of about Rs 10,372 crore over five years. Its plans include shared GPU computing for researchers and startups, datasets, skills and "safe and trusted AI".
Why it mattered. Training neural networks needs huge computing power, and the mission aims to make it available within India.
John Hopfield and Geoffrey HintonStockholm, Sweden
The Royal Swedish Academy of Sciences gave the Nobel Prize in Physics to John Hopfield and Geoffrey Hinton "for foundational discoveries and inventions that enable machine learning with artificial neural networks". Both had borrowed tools from physics to build their networks.
Why it mattered. It was the first Nobel Prize given for work on artificial neural networks.
The Global E-waste Monitor 2024 reported that the world threw away 62 million tonnes of electronics in 2022, and only 22.3% was properly collected and recycled.
Why it mattered. Old phones hold gold, copper and cobalt: recycling them matters.
On Wallace & Gromit: Vengeance Most Fowl, up to 30 animators each made about 4.2 seconds of animation a week, shooting on digital stills cameras with Dragonframe frame-grab software, mostly on twos.
Why it mattered. The tools changed, but the pace of hand-made animation did not.
Sample Registration System, Registrar General of IndiaIndia
The Sample Registration System, which tracks births and deaths in a large national sample, reported a maternal mortality ratio of 88 deaths per 100,000 live births for 2020–22. In 1997–98 it had been 398.
Why it mattered. It is a fall of more than three-quarters in about 25 years, though some states still have far higher rates.
WHO's Global Hepatitis Report said 254 million people were living with hepatitis B and 50 million with hepatitis C in 2022. Viral hepatitis killed about 1.3 million people a year. India had about 29.8 million people with hepatitis B and 5.5 million with hepatitis C, the second largest total after China.
Why it mattered. We have a vaccine and a cure, but most people with hepatitis still have not been tested.
A review of 1,748 studies from 111 countries found that the share of people with H. pylori fell from about 58% in 1980–1990 to about 43% in 2011–2022, though it is still common, especially in children in many countries.
Why it mattered. Stomach ulcers and stomach cancer are becoming rarer in many places as the germ declines.
The strongest magnetic storm in two decades pushed the aurora so far south that all-sky cameras at the Indian Astronomical Observatory in Hanle recorded a red glow over the Himalaya. Scientists in Bengaluru later traced it to several merging eruptions from the Sun.
Why it mattered. It was a reminder that the Earth's magnetic shield is always being tested by the Sun.
At the 66th Grammy Awards, Zakir Hussain won three awards: for Shakti's album This Moment, and for the track Pashto and the album As We Speak with Béla Fleck, Edgar Meyer and Rakesh Chaurasia. He became the first musician from India to win three Grammys at one ceremony. India had given him its second-highest civilian honour, the Padma Vibhushan, in 2023.
Why it mattered. It crowned the tabla as a truly global instrument.
Ustad Zakir Hussain (1951–2024)San Francisco, California
Zakir Hussain, the son and student of Alla Rakha, died in San Francisco at the age of 73. He had played tabla since childhood and worked with musicians from every corner of the world. Tributes poured in from India and far beyond.
Why it mattered. His life carried the Punjab gharana from his father's lessons to stages all over the planet.
The United States finalised new efficiency rules for home water heaters, due to apply to heaters made from 2029. The department expected more than half of new electric storage heaters to use heat pumps, up from about 3%.
Why it mattered. It marks a shift from heating water with a simple hot coil to moving heat from the air.
Versuni opened a factory in Ahmedabad to make Philips Airfryers in India for the first time. It planned to start at 500,000 air fryers a year, with room to grow, and to create more than 1,000 jobs. In 2026 it added a line making air fryer motors at its Chennai plant.
Why it mattered. India had become big enough to build air fryers at home, not just buy them.
India launched PM Surya Ghar: Muft Bijli Yojana, a plan worth ₹75,021 crore to help about 1 crore (10 million) households put solar panels on their roofs. Families can get up to 300 units of free electricity a month. Every rooftop system needs an inverter to turn the panels' DC into AC.
Why it mattered. The inverter is changing from a power-cut backup into the heart of a home solar system.
Google announced Veo 3, which generated speech, sound effects and music together with the video in a single model. Widely shared clips of talking characters made it hard to tell AI video from real footage at a glance.
Why it mattered. Realistic talking video made labels and provenance more urgent.
MIT Technology Review; Hugging Face researchersUnited States and Canada
Measurements on one open model found a 5-second clip used about 3.4 million joules, more than 700 times a high-quality image. A Hugging Face study found that doubling a video's length roughly quadruples the energy needed.
Why it mattered. Video is the most energy-hungry thing most people ask AI to make.
Cyberspace Administration of China and three other agenciesBeijing, China
China's labelling measures took effect, requiring visible labels on AI-made content such as video, plus hidden labels in the file's data. In Europe, the AI Act's Article 50 requires AI-made deepfakes to be disclosed, with those rules applying from August 2026.
Why it mattered. Several large markets moved from asking to requiring AI labels.
OpenAI released Sora 2, which added synchronised speech and sound, in a social app where people could put themselves into videos. It spread quickly, and so did complaints about copyright and look-alike videos of real people.
Why it mattered. AI video became something people shared in a feed, raising new questions about consent.
Ministry of Electronics and Information Technology (MeitY)New Delhi, India
MeitY published draft amendments to the IT Rules defining "synthetically generated information". The draft proposed that visible labels cover at least 10% of the screen, or play during the first 10% of an audio clip, and asked the public for comments.
Why it mattered. It was the first draft Indian law written specifically about AI-made media.
The IEA's Energy and AI report estimated that data centres used about 415 TWh in 2024, around 1.5% of the world's electricity, and could reach about 945 TWh by 2030, with AI the main driver.
Why it mattered. It gave governments a shared, careful baseline for the energy cost of AI.
Google reported that a median text prompt to its Gemini app used about 0.24 Wh of energy and 0.26 mL of water, and said the figure had fallen 33-fold in a year. Epoch AI had earlier estimated about 0.3 Wh for a typical GPT-4o query.
Why it mattered. Per-answer figures finally became public, though they are company numbers that are hard to check.
Google reported that a median text prompt to its Gemini app used about 0.24 watt-hours of energy and 0.26 ml of water. Independent estimates for other models vary widely, and total AI electricity demand keeps rising.
Why it mattered. Energy use per answer is small, but billions of answers add up.
Central Board of Secondary Education (CBSE)New Delhi, India
Indian school board exams have long barred calculators, except for some students with special needs, so generations learned to work sums by hand. In a governing body meeting in December 2024, CBSE decided to allow basic, non-programmable calculators in the Class 12 Accountancy exam from the 2025–26 session, as reported in the press. Rules differ between boards.
Why it mattered. Deciding when a calculator helps learning, and when it gets in the way, is still a live question in classrooms.
India had roughly 12,000 to 13,000 single-screen halls in the 1980s. The FICCI-EY 2026 report counted 10,033 screens of all kinds in 2025, as multiplexes grew and many single screens shut, especially after the Covid-19 pandemic. In 2025 alone, 240 screens opened and 124 closed, mostly single screens.
Why it mattered. Digital projectors made it cheap to run many small screens in one building, reshaping where India watches films.
Disney Research, Pixar, ILM and Walt Disney Animation; Intel's Open Image Denoise teamLos Angeles, USA
The Academy honoured Disney's machine-learning denoiser, used since 2018 on over 100 films and shows including Toy Story 4. It also honoured Intel's Open Image Denoise, a free denoiser first released in 2019 and used in renderers such as Arnold. Cleaning up noise had become as important as tracing the rays.
Why it mattered. AI denoising is now a standard final step in path-traced rendering.
Flow, a wordless film about a cat in a flooded world, was made entirely in Blender and rendered with its real-time engine, EEVEE, by a small team. It won the Academy Award for Best Animated Feature.
Why it mattered. The free tool from 2002 and real-time rendering reached the top of the industry.
Desi Oon, a stop-motion film made from wool about India's native sheep wool, won a jury award in the commissioned films section at the Annecy animation festival. Over 50 artists worked on it for six months of filming.
Why it mattered. It showed Indian studios inventing new stop-motion materials.
The consulting firm Kearney estimated India's air fryer market at 600 to 700 crore rupees in 2025, growing 14 to 16% a year, and about 2.3 million were sold. People air fry paneer, kebabs and vegetables as well as chips. Amazon India said nearly 9 in 10 of its air fryer buyers were getting their first one.
Why it mattered. Air frying is spreading fast in one of the world's great frying cultures.
India had about 32.94 crore active domestic LPG customers, more than double the 14.52 crore of April 2014. But a 2023–24 government survey found only about 60% of households used LPG as their main cooking fuel, with a third still using firewood.
Why it mattered. Having a cylinder is not the same as using it every day; the last step is making gas affordable enough to replace the chulha.
BloombergNEF's yearly survey found the average lithium-ion battery pack fell to $108 per kilowatt-hour, 93% cheaper than in 2010. Packs for stationary storage, like home and grid batteries, were the cheapest of all at $70. Lithium iron phosphate packs averaged $81, well below other kinds.
Why it mattered. Lithium batteries are becoming cheap enough to replace lead-acid next to the home inverter.
Only about 5% of Indian households owned a microwave oven in 2013, far fewer than owned a fridge. Sales are growing as cities grow, and one market research firm valued India's microwave market at about US$572 million in 2025. Convection models that can also bake and grill are popular.
Why it mattered. The microwave is still spreading, and much of its next growth is in Asia.
Drivers and carmakers worldwide, led by ChinaWorldwide
More than 20 million electric cars were sold in 2025, a quarter of all new cars, says the International Energy Agency. Six in ten were sold in China, where close to 55% of new cars were electric. China's BYD sold more fully electric cars than Tesla for the first time.
Why it mattered. Just over a century after it lost to petrol, the electric car is taking over again.
People in the hottest places on EarthThe tropics and beyond
About 3.5 billion people live in regions with high temperatures, but only about 15% of them own an air conditioner, says the IEA. As heat waves grow, demand is soaring in India, Southeast Asia and Africa.
Why it mattered. Cooling is becoming a matter of health, and making it efficient will shape the climate.
Rubin's LSST camera, about the size of a small car, has a 3,200 megapixel sensor. Its first images were released in 2025, and it will photograph the whole southern sky every few nights for ten years.
Why it mattered. From 0.01 megapixels in 1975 to 3,200 in 50 years.
A case report described a woman with brain swelling after months of taking a Siddha medicine whose capsules held mercury, lead and arsenic thousands of times above safe limits.
Why it mattered. It is a reminder to use only licensed products and to tell doctors what you take.
Ministry of Electronics and Information Technology (MeitY)New Delhi, India
The amended IT Rules, in force from 20 February 2026, require AI-made audio and video to carry a prominent label and metadata that platforms must not strip. The fixed 10% size was dropped. Platforms must remove unlawful content within 3 hours of a lawful order, and non-consensual intimate images, including deepfakes, within 2 hours.
Why it mattered. India now has some of the world's strictest labelling and takedown rules for AI video.
OpenAI announced it would close the Sora app, which shut on 26 April 2026, with the API ending in September. News reports pointed to very high running costs and problems with copyright and deepfakes.
Why it mattered. Making video is expensive, and even a famous product could not cover its costs.
Fax lives on in clinics, courts, pharmacies and government offices, often as T.38 over the internet or as online fax services that turn pages into emails.
Why it mattered. A 180-year-old idea, scan a page line by line and keep both ends in step, is still at work.
Double-decker buses must lean to 28° on a tilt table without rolling over. Car specs list torque beside power, electric motors give full torque from standstill, and e-bikes measure your pedal torque to decide how much to help.
Why it mattered. From seesaws to scooters, balancing and making torque is everyday engineering.
Kaundinya is a wooden sailing ship built without nails, its planks stitched with coconut-fibre rope in an old Indian technique, to a design based on a 5th-century ship painted in the Ajanta caves. Kerala shipwrights led by Babu Sankaran built it. It sailed from Porbandar on 29 December 2025 and reached Muscat about 18 days later.
Why it mattered. It revives, with care and some guesswork, the kind of craft that carried Indian Ocean trade.
A survey in December 2025 found that 65% of UK households owned an air fryer, up from about 30% in 2022. Most owners use it several times a week. Food makers now test and print air fryer instructions on packets, next to oven times.
Why it mattered. In just a few years the air fryer joined the oven and microwave as a normal way to cook.
Ministry of Power and Bureau of Energy EfficiencyNew Delhi, India
Under a rule notified in October 2024, India's star bands for fridges tightened by one star on 1 January 2026. A frost-free fridge that earned 5 stars in 2025 now has to use about 12% less electricity to keep them. For a 250-litre frost-free fridge, 5 stars now means under about 163 kWh a year, while a 1-star model uses about 245 to 282 kWh.
Why it mattered. The bar keeps rising, so a fridge's stars only make sense next to the year on its label.