The history of trying to understand the world.
135 stories in this theme.
At its height around 1200, Greater Angkor covered some 1,000 km² and may have held close to a million people, sustained by a vast engineered water network. By the mid-15th century the court was gone to the south. Not 'lost' — Angkor Wat never ceased to be a shrine — the city was undone, modern research suggests, by its own infrastructure meeting megadroughts and floods.
Read the story →When Nevado del Ruiz erupted on 13 November 1985, its melting ice cap sent lahars — volcanic mudflows — down river valleys onto the sleeping town of Armero, Colombia. Around 23,000 of its 29,000 inhabitants died. Hazard maps had predicted the flow path almost exactly; evacuation never happened.
Read the story →On 1 September 1859 astronomer Richard Carrington watched a white flash erupt on the Sun. Within a day the largest geomagnetic storm on record hit Earth — auroras were seen near the equator, telegraph lines sparked and shocked their operators, and some circuits ran on auroral current alone. A repeat today would be a global infrastructure disaster.
Read the story →In February 1959 nine experienced Soviet ski-hikers died on the slope of Kholat Syakhl in the northern Urals. Their tent was found cut open from the inside; the bodies lay up to 1.5 km away, some barefoot in the snow, some with severe internal injuries. Sixty years of theories followed. The modern scientific verdict is a slab avalanche.
Read the story →Pittsburgh industrialist and amateur golf champion Eben Byers began drinking Radithor — certified radium dissolved in water — in 1927, at up to three bottles a day. By 1931 his bones were disintegrating and his jaw had been surgically removed. His death in March 1932 killed the radioactive patent-medicine industry, under the Wall Street Journal's immortal headline.
Read the story →Franz Reichelt, an Austrian-born Parisian tailor, designed a wearable parachute suit and obtained permission to test it from the Eiffel Tower — with a dummy. On the morning of 4 February 1912, before Pathé news cameras, he jumped himself. The suit failed and he fell 57 metres to his death.
Read the story →By the 1890s London and New York ran on tens of thousands of horses, each producing over 10 kilograms of manure a day. Urban commentators projected streets buried metres deep within decades; the 1898 international urban planning conference reportedly broke up with no solution. The automobile made the entire problem vanish — a favourite parable with a catch: its most famous quotation cannot be traced.
Read the story →From 5 to 9 December 1952 a windless anticyclone trapped London's coal smoke at street level. Visibility fell to arm's length, transport stopped, and cattle died at Smithfield. The official count was around 4,000 deaths; modern analyses put the toll at 10,000-12,000. It produced the Clean Air Act of 1956.
Read the story →Astronomers announced that on 18-19 May 1910 the Earth would pass through the tail of Halley's Comet — and that the tail contained cyanogen, a poison. Amplified by newspapers and a famous astronomer's speculation, the news spawned sealed rooms, comet pills, and gas masks. Mark Twain, born under the comet in 1835, died as it returned — as he had predicted.
Read the story →John Harrison, a self-taught Yorkshire carpenter, spent his life building clocks accurate enough to carry longitude to sea. His 1759 watch H4 lost only seconds on a transatlantic trial — meeting the £20,000 Longitude Prize's terms — but the Board of Longitude paid in grudging halves until King George III himself intervened. A copy of H4 guided Captain Cook.
Read the story →On 15 January 2022 the submarine volcano Hunga Tonga-Hunga Ha'apai erupted with a blast heard in Alaska, 9,700 km away. Its plume reached 57 km — the first ever observed to enter the mesosphere — its pressure wave circled the Earth for days, and it injected an unprecedented mass of water vapour into the stratosphere. Tonga was cut off from the world for days by a severed cable.
Read the story →On the night of 21 August 1986, Lake Nyos in Cameroon released an estimated 1.6 million tonnes of carbon dioxide in a rare limnic eruption. The invisible, ground-hugging cloud flowed down the valleys and suffocated 1,746 people and some 3,500 head of livestock, most without waking.
Read the story →The French astronomer Guillaume Le Gentil left home in 1760 to observe the transit of Venus from India. War kept him at sea for the 1761 transit; he waited eight more years for the 1769 one — which a single cloud obscured. He returned after eleven and a half years to find himself declared dead, his wife remarried, and his estate divided.
Read the story →From 1932 the Chisso Corporation discharged methylmercury into Minamata Bay, Japan. The neurological disease it caused was officially identified on 1 May 1956; Chisso's own physician proved the cause by 1959 and was silenced. The dumping continued until 1968. Thousands were certified as victims; the true number is far higher.
Read the story →On 13 September 1848, a premature blast drove a 43-inch tamping iron through the skull of railroad foreman Phineas Gage at Cavendish, Vermont — in under his cheekbone, out the top of his head. He was speaking within minutes, lived another eleven and a half years, and became the most famous case in the history of neuroscience.
Read the story →China's First Emperor was buried in 210 BC beneath a man-made mountain near Xi'an, guarded — the historian Sima Qian wrote — by crossbow traps, with rivers of mercury flowing across a model of his empire. In 1974 farmers digging a well found his terracotta army. The burial chamber itself has never been opened — and the soil above it really is laced with mercury.
Read the story →From 1917, young women painting luminous watch dials were taught to point their brushes with their lips, swallowing radium with every stroke. As their jaws crumbled and their bones fractured, the companies denied everything. Grace Fryer's 1927-28 lawsuit against US Radium became a landmark of workers' rights.
Read the story →Between roughly 1250 and 1500, the people of Rapa Nui — the most remote inhabited island on Earth — carved nearly a thousand moai and moved statues of many tonnes kilometres without wheels or draft animals. The famous 'ecocide' parable of a society that destroyed itself has been heavily revised: the catastrophic collapse came after European contact — slave raids and smallpox reduced the population to 111 by 1877.
Read the story →On the night of 22 October 1707, a Royal Navy fleet returning from the Mediterranean — its position miscalculated — drove onto the rocks of the Isles of Scilly. Four ships and up to 2,000 men were lost, Admiral Sir Cloudesley Shovell among them. The catastrophe pushed Parliament to the Longitude Act of 1714 and its £20,000 prize.
Read the story →Mary Mallon, an Irish-born cook in New York, was the first person in the United States identified as a healthy carrier of typhoid fever. Linked to at least 53 cases and 3 deaths, she was quarantined on North Brother Island from 1907 to 1910, released on condition she stop cooking — and caught cooking again in 1915. She spent the rest of her life in quarantine.
Read the story →On the morning of 30 May 1626 the Wanggongchang Armoury — a major gunpowder works inside Beijing — detonated, devastating roughly two square kilometres of the capital and killing a reported 20,000 people. The emperor's infant heir died in the aftermath; contemporary accounts are so strange that theories still multiply around one of the largest accidental explosions of the pre-industrial world.
Read the story →Ada Lovelace's 1843 translation-and-commentary on Luigi Menabrea's paper on Charles Babbage's Analytical Engine contains, in Note G, what is now considered the first published computer program. The Analytical Engine was never built in Babbage's lifetime. Ada died of cancer at 36, the same age as her father.
Read the story →Muhammad ibn Musa al-Khwarizmi worked at the House of Wisdom in Baghdad under Caliph al-Ma'mun in the 820s. His *al-Kitāb al-mukhtaṣar fī ḥisāb al-jabr wa-l-muqābala* gave Europe the word algebra. The Latinised version of his name — algoritmi — gave Europe the word algorithm. He introduced the Hindu decimal numeral system to the Arabic-speaking world and from there to Europe.
Read the story →Alan Turing was found dead at his Wilmslow home on 8 June 1954, aged 41. The coroner ruled suicide by cyanide poisoning; a half-eaten apple lay beside the bed. The Crown Prosecution Service had convicted him of gross indecency two years earlier and ordered chemical castration as an alternative to prison. The pardon arrived in 2013.
Read the story →Anna Anderson was pulled from a Berlin canal in February 1920 and claimed to be Grand Duchess Anastasia Nikolaevna of Russia, surviving daughter of Tsar Nicholas II. She maintained the claim through forty-five years of litigation and three biographies. DNA analysis in 1994 — three years after her 1984 cremation — identified her as the Polish factory worker Franziska Schanzkowska.
Read the story →Apollo 1 was a ground rehearsal test, not a launch. At 6:31 p.m. on 27 January 1967 a spark in the pressurised pure-oxygen cabin atmosphere ignited Velcro and nylon webbing. Gus Grissom, Ed White, and Roger Chaffee died of asphyxiation within seventeen seconds. The hatch design — inward-opening, requiring 90 seconds to remove — could not be opened against the internal pressure spike.
Read the story →Archimedes was asked by King Hiero II of Syracuse to determine whether a goldsmith had fraudulently substituted silver for some of the gold in a royal crown. The principle of displacement — that a submerged body displaces a volume of water equal to its own volume — occurred to Archimedes in the public bath. He reportedly ran home shouting "Eureka!" without dressing. The first surviving record of the story is Vitruvius, two centuries later.
Read the story →Charles Babbage received approximately £17,500 of British government funding between 1823 and 1842 to build the Difference Engine, a brass mechanical calculator for producing accurate mathematical tables. He never finished it. His subsequent Analytical Engine (1837) was a general-purpose programmable computer that he also never built. A complete Difference Engine No. 2 to his original 1849 specifications was built by the Science Museum London in 1991 and works.
Read the story →Approximately 27 tonnes of methyl isocyanate gas leaked from a storage tank at the Union Carbide India Limited pesticide plant in Bhopal between approximately 23:00 on 2 December and 02:00 on 3 December 1984. The toxic cloud spread across adjacent shantytowns. The Indian government's official immediate death toll is 3,787. Independent estimates of total deaths from acute and chronic exposure reach 20,000 or more.
Read the story →Tycho Brahe kept a tame moose at his Bohemian residence in the late 1590s. According to a letter Tycho wrote to a friend, the animal was lent to a neighbouring nobleman for a banquet, drank too much beer, and broke its neck falling down a flight of stairs while attempting to descend after the meal.
Read the story →Caroline Herschel (1750-1848) was a 4-foot-3 former kitchen servant who became the senior assistant in her brother William Herschel's astronomical observatory at Slough. She discovered eight comets between 1786 and 1797, catalogued 561 new stars and 14 nebulae, and was the first woman in any country paid by a national government as a working scientist — £50 per year from George III from 1787.
Read the story →The Space Shuttle Challenger broke apart 73 seconds after launch on 28 January 1986, killing all seven crew. The proximate cause was the failure of a rubber O-ring seal on the right solid rocket booster at the unusually cold overnight launch temperature. The engineers at the manufacturer Morton Thiokol had argued against the launch for thermal reasons the night before; they had been overruled by their own management on a NASA conference call.
Read the story →Jean-François Champollion announced his decipherment of the Egyptian hieroglyphic script on 22 September 1822 — the famous *Lettre à M. Dacier*. He had been working on the problem for fourteen years. He reportedly fainted on the day of the breakthrough and was bedridden for five days. He died ten years later, aged 41.
Read the story →The RBMK-1000 reactor at Chernobyl Reactor Block 4 exploded at 1:23:40 a.m. on 26 April 1986 during a poorly-managed safety test. The reactor lid blew off. Graphite moderator caught fire. The 10-day fire released approximately 400 times more radioactive material than the Hiroshima atomic bomb. Approximately 350,000 people were eventually evacuated permanently from the 30-km exclusion zone.
Read the story →Émilie du Châtelet's French translation and mathematical commentary on Newton's *Principia* was completed in summer 1749 while she was carrying a fourth child at age 42. She finished the manuscript at Lunéville on 1 September 1749, gave birth on 4 September, and died of puerperal fever on 10 September. The translation, published posthumously in 1759, remained the standard French Newton until the 20th century.
Read the story →The Exxon Valdez supertanker ran aground on Bligh Reef in Prince William Sound, Alaska, at 00:04 local time on 24 March 1989. Approximately 41,600 cubic metres (260,000 barrels) of Alaska North Slope crude oil spilled into the sound. The spill killed an estimated 250,000 seabirds and remained the largest US coastal oil spill until the 2010 Deepwater Horizon disaster.
Read the story →Florence Nightingale arrived at the Scutari military hospital outside Constantinople on 4 November 1854 with 38 trained nurses to handle British casualties from the Crimean War. The death rate from disease in the overcrowded wards was 42 percent. Six months of systematic reform — hand-washing, ventilation, sewer cleaning, nutrition — brought it to 2 percent. Modern nursing dates its institutional origin from this campaign.
Read the story →Benjamin Franklin's June 1752 kite-and-lightning experiment is one of the most-told stories in the history of science. The contemporary documentation is thin. Modern historians of science consider it possible that Franklin never actually performed it.
Read the story →The 11 March 2011 earthquake off northeastern Honshu produced a 14-metre tsunami that overwhelmed the seawall of the Fukushima Daiichi nuclear power plant at 15:41 local time. Backup diesel generators flooded within minutes. Without cooling, three reactor cores went into meltdown over the substantial subsequent four days. The displaced population was about 154,000.
Read the story →Galileo Galilei demonstrated his improved 8x telescope to the Venetian Senate from the bell tower of San Marco on 21 August 1609. The senators looked at distant ships approaching the lagoon, decided that the strategic value was substantial, and doubled Galileo's University of Padua salary to 1,000 florins per year. He was a month away from turning the same instrument on the night sky.
Read the story →Giordano Bruno was burned at the stake in the Campo dei Fiori, Rome, on 17 February 1600. The Roman Inquisition's verdict identified eight specific theological errors. Among them were the doctrines of an infinite universe with countless inhabited worlds. He was 52. His statue at the execution site was erected in 1889 by an Italian liberal-republican fund-raising campaign against the modern Vatican.
Read the story →The Dow Jones Industrial Average fell 12.8 percent on Black Monday 28 October 1929 and 11.7 percent on Black Tuesday 29 October 1929. The Crash initiated a global Great Depression that bottomed in 1933 with US unemployment at approximately 25 percent and approximately 9,000 US banks failed. Industrial production took a decade to return to 1929 levels.
Read the story →Hedy Lamarr, MGM star, and George Antheil, modernist composer, jointly received US Patent 2,292,387 on 11 August 1942 for a frequency-hopping torpedo guidance system. The US Navy filed it away. The patent expired unused in 1959. Modern Bluetooth, GPS, and Wi-Fi rest on the same principle.
Read the story →Henrietta Lacks died of cervical cancer at Johns Hopkins on 4 October 1951, aged 31. A tissue sample taken before her death became the HeLa cell line — the first human cells to grow indefinitely in laboratory culture. They have produced almost every major biomedical breakthrough of the subsequent 70 years. Her family did not know until 1973.
Read the story →The American B-29 Enola Gay dropped a uranium-235 fission bomb on Hiroshima at 8:15 a.m. on 6 August 1945. The bomb detonated approximately 580 metres above the city centre and killed approximately 70,000 people instantly. By the end of 1945 the cumulative death toll from blast, burns, and acute radiation sickness had reached approximately 140,000. Japan surrendered nine days later.
Read the story →At the British Association meeting in Oxford on 30 June 1860, seven months after Darwin's *Origin of Species*, the Bishop of Oxford Samuel Wilberforce asked T. H. Huxley whether he claimed descent from apes on his grandfather's or grandmother's side. Huxley reportedly replied that he would rather be descended from an ape than from a bishop who used his great abilities to obscure the truth. The exchange did not happen exactly as the legend records.
Read the story →Ibn Sina's *Canon of Medicine*, compiled at Isfahan around 1025, synthesised Greek, Roman, Persian, and Arabic medical traditions into a five-volume systematic treatise. Translated into Latin in Toledo by Gerard of Cremona around 1180, it became the standard medical-school textbook at Paris, Padua, Montpellier, and Bologna for almost five centuries. The first English translation appeared in 1930.
Read the story →John Dee was the senior English mathematician of the late 16th century, court astrologer to Elizabeth I, scientific adviser to the substantial early English exploration ventures, and possibly the first English-language writer to use the phrase 'British Empire.' He also believed he was communicating with angels through a polished obsidian mirror.
Read the story →Vladimir Komarov launched in Soyuz 1 on 23 April 1967 knowing the spacecraft had 203 documented engineering faults. He flew it anyway because the backup pilot was Yuri Gagarin and Komarov refused to let Gagarin take the risk. After 18 orbits the descent module's main parachute failed to deploy. Komarov hit the Orenburg Steppe at approximately 140 km/h and was killed instantly. He was 40.
Read the story →Joseph Lister introduced carbolic acid antiseptic surgery at the Glasgow Royal Infirmary in 1865 after reading Pasteur's germ-theory work. Post-operative mortality on his ward fell from about 46% to about 15% within three years. The British medical establishment took a substantial fifteen years to accept the method.
Read the story →The Lunar Society of Birmingham met about fourteen times a year between approximately 1765 and 1813, always on the Monday nearest the full moon (so members could ride home by moonlight). The members included James Watt, Matthew Boulton, Joseph Priestley, Erasmus Darwin, and Josiah Wedgwood. They built the Industrial Revolution in their spare time.
Read the story →Maria Sibylla Merian, a 52-year-old Frankfurt-born artist and naturalist, sailed alone with her younger daughter to the Dutch colony of Suriname in June 1699. Over two years she documented the life cycles of approximately 90 South American insect species, ate the same food as her enslaved Indigenous and African informants, and produced the 1705 *Metamorphosis Insectorum Surinamensium* — one of the founding works of modern entomology.
Read the story →Marie Curie won the Nobel Prize in Physics in 1903 and in Chemistry in 1911. She died of aplastic anaemia at 66 in 1934 — a substantial direct consequence of forty years of unprotected exposure to the radium and polonium she had isolated. Her laboratory notebooks remain radioactive and are kept in lead-lined boxes.
Read the story →Mary Anning found her first complete ichthyosaur on the Lyme Regis cliffs in 1811 when she was twelve. She spent the next thirty-five years collecting and selling the foundational fossils of British vertebrate palaeontology. The Geological Society of London — to which she had supplied the substantial majority of its early-century specimens — admitted no women until 1904.
Read the story →In June 1816 at the Villa Diodati on Lake Geneva, Lord Byron proposed that his five guests each write a ghost story. The volcanic winter from the Tambora eruption had ended summer in Europe. Mary Godwin, 18, wrote the opening of *Frankenstein*. Dr John Polidori wrote *The Vampyre*. Modern science fiction and modern vampire fiction began in the same villa in the same week.
Read the story →Dmitri Mendeleev published the first version of the periodic table in March 1869. He later told biographers he had seen the arrangement in a dream after three days of fruitless waking work. The dream story is probably substantially embellished, but the table works.
Read the story →Apollo 11 commander Neil Armstrong and lunar module pilot Buzz Aldrin landed the Lunar Module Eagle in the Sea of Tranquility at 20:17 UTC on 20 July 1969. Armstrong stepped onto the lunar surface at 02:56 UTC on 21 July 1969. The two astronauts spent 2 hours 31 minutes outside the spacecraft and returned with 21.55 kg of lunar samples.
Read the story →An earthquake-triggered landslide on the north face of Mount St Helens at 08:32:11 PDT on 18 May 1980 unblocked a pressurised magma chamber. The resulting lateral blast removed approximately 400 metres of the volcano's summit, levelled 600 square kilometres of forest, and killed 57 people. It is the deadliest volcanic event in US history.
Read the story →Olbers' paradox asks why the night sky is dark rather than uniformly bright. In an infinite, eternal, static universe with uniformly distributed stars, every line of sight should eventually intersect a stellar surface — making the entire sky as bright as the sun. The answer requires the universe to be finite in age, or expanding, or both.
Read the story →The Piltdown skull was unveiled by Charles Dawson at the Geological Society of London on 18 December 1912 as *Eoanthropus dawsoni* — the missing link between ape and human. It dominated British palaeoanthropology for forty years. The 1953 fluorine and chemical testing proved it was a modern human cranium combined with an orangutan jaw, stained with iron and chromium, with the teeth filed flat.
Read the story →Rosalind Franklin produced X-ray diffraction Photo 51 of DNA in May 1952. Maurice Wilkins showed it to James Watson in January 1953 without her knowledge. The Watson-Crick double-helix paper appeared in *Nature* on 25 April 1953. Franklin died of ovarian cancer on 16 April 1958, aged 37. The 1962 Nobel Prize went to Watson, Crick, and Wilkins.
Read the story →Ignaz Semmelweis demonstrated in 1847 that the catastrophic maternal mortality of the Vienna General Hospital's First Obstetric Clinic was caused by doctors arriving from the dissection room with unwashed hands. Handwashing in chlorinated lime substantially eliminated the mortality. The European medical establishment rejected the finding. Semmelweis was committed to an asylum and beaten to death there in 1865.
Read the story →Gaspare Tagliacozzi's *De Curtorum Chirurgia per Insitionem* (1597) described the first systematic European reconstructive surgical technique for nose loss — using a substantial skin flap rotated from the patient's upper arm. The technique required the patient to keep the arm strapped to the face for several weeks while the graft established blood supply.
Read the story →Nikola Tesla's Wardenclyffe Tower on Long Island was 187 feet tall, built between 1901 and 1903 as a global wireless-power transmission station. J.P. Morgan stopped funding it in 1903. Tesla mortgaged the tower in 1915 and lost the property in 1917 when the steel was sold for $1,750 scrap value. The site is now the Tesla Science Center.
Read the story →King Frederick II of Denmark granted Tycho Brahe the island of Hven in the Øresund Strait in February 1576 with funding to build a state-supported astronomical observatory. The resulting Uraniborg and Stjerneborg observatories operated from 1576 to 1597 and produced the most accurate pre-telescopic positional astronomy in history. The data set was the foundation on which Kepler's three laws of planetary motion were derived.
Read the story →Andreas Vesalius's *De humani corporis fabrica*, published at Basel in June 1543, was an anatomical atlas based on the direct dissection of approximately thirty human cadavers in Padua between 1540 and 1542. The book identified approximately 200 specific errors in Galen's anatomy. The conclusion that Galen had dissected only animals — never humans — ended 1,300 years of medical-faculty authority.
Read the story →Alfred Russel Wallace, a self-funded specimen-collecting naturalist, was lying in a malarial fever on the island of Ternate in the eastern Dutch East Indies in February 1858 when he worked out the theory of natural selection. He wrote it up in two days and posted the manuscript to Charles Darwin. Darwin had been refining the same theory privately for twenty years. The two papers were read together at the Linnean Society on 1 July 1858.
Read the story →The Wright brothers flew the world's first powered, heavier-than-air, sustained, controllable aircraft on the morning of 17 December 1903 at Kitty Hawk, North Carolina. The first flight covered 36 metres in 12 seconds. The fourth flight that day covered 260 metres in 59 seconds. Within 66 years the same trajectory of aviation development had landed humans on the Moon.
Read the story →Ada King, Countess of Lovelace, was the only legitimate child of Lord Byron — born in December 1815, separated from him within weeks, never seeing him again. She grew up under intensive maternal anti-Byron mathematical discipline and produced in 1843 the seven Notes on the Analytical Engine that contain what is now considered the first published computer program.
Read the story →Edward Walter Maunder was Royal Greenwich Observatory's senior solar astronomer from 1873 to 1913. He identified the unusual 1645–1715 sunspot deficit in the Greenwich archive and substantially defined it as a coherent solar-activity phenomenon. He married his junior collaborator Annie Russell in 1895 — and her contribution to the work was substantially larger than the published record acknowledged.
Read the story →Galileo Galilei was tried by the Roman Inquisition between February and June 1633 on the charge of vehement suspicion of heresy. He was 68, ill, and threatened with formal torture. He recanted publicly on 22 June 1633 and was sentenced to indefinite house arrest. The Catholic Church formally rehabilitated him in 1992.
Read the story →John Snow administered chloroform or ether to approximately 4,000 surgical patients between 1847 and his death in 1858, including Queen Victoria. He kept a detailed daily logbook of every case — patient name, operation, dose, response, complications. The logbook survives. It is the most complete primary record of mid-19th-century clinical anaesthesia practice anywhere.
Read the story →Classical and medieval tradition holds that Archimedes used a system of polished bronze mirrors to focus sunlight on the Roman ships besieging Syracuse, setting them on fire. The story is first attested 350 years after the siege. Modern experimental reconstructions have produced ambiguous results.
Read the story →Eudoxus of Cnidus proposed in the 360s BC that the apparent motions of the planets could be explained by a system of 27 concentric rotating spheres centred on the Earth. Aristotle expanded the model to 55 spheres. The framework substantively defined European cosmology until Tycho Brahe.
Read the story →Guy de Chauliac served as personal physician to Popes Clement VI, Innocent VI, and Urban V at Avignon between 1342 and 1370. His *Chirurgia Magna* (1363) was the dominant European surgical textbook from the 14th century to the 17th — and contained the most detailed eyewitness account of the 1348 Black Death by a doctor who survived it.
Read the story →Hippocrates of Chios was a Greek geometer of the late 5th century BC — not the famous physician of Cos. He was the first European mathematician to compute the exact area of a region bounded by curves, an achievement that opened the path Eudoxus and Archimedes would later complete with the method of exhaustion.
Read the story →Hippocrates of Cos and Hippocrates of Chios were near-contemporaries — both Greek, both prominent in their fields, both with the same first name — and were occasionally confused even by ancient sources. One founded the European medical tradition; the other wrote the first textbook of European geometry.
Read the story →Strabo of Amaseia wrote the seventeen-book *Geographika* between approximately 20 BC and 23 AD. The work was substantially the last great Hellenistic geographical synthesis. Strabo disagreed with most of Eratosthenes's specific positions on geographical method, but cited him so extensively in the process of disagreeing that Strabo is now the principal surviving source for Eratosthenes's lost work.
Read the story →Annie Scott Dill Russell Maunder was a Cambridge-trained mathematician who spent thirty years at the Royal Greenwich Observatory photographing the Sun. She discovered the substantive equator-ward drift of sunspots through the solar cycle and co-authored the historical work that gave her husband Edward Maunder credit for what should have been a joint discovery.
Read the story →Aristarchus of Samos proposed around 270 BC that the Earth orbits the Sun, not the other way around. The classical and late-antique Greek astronomical mainstream — including Hipparchus and Ptolemy — rejected the proposal on empirical grounds. The work survives only through a single passage in Archimedes.
Read the story →Chares of Lindos was the Rhodian sculptor who built the 33-metre bronze Colossus of Rhodes between approximately 292 and 280 BC. He had been a pupil of Lysippos. Late-antique tradition claims he killed himself when he discovered a substantial computational error in the statue's stress profile. The Colossus stood for 54 years and was knocked down by an earthquake in 226 BC.
Read the story →The Eratosthenian Earth circumference (about 250,000 stadia, accurate to 2%) was the standard ancient figure but had been substantially undermined by a competing late-antique calculation by Posidonius. Columbus took the smaller Posidonian figure as his planning baseline. If he had used Eratosthenes's number, he would never have sailed.
Read the story →David Fabricius was a Lutheran pastor and astronomer in East Frisia who corresponded with Tycho Brahe and Kepler, observed the first known variable star (Mira Ceti) in 1596, and made independent sunspot observations in 1611. He was killed in May 1617 by a parishioner he had accused from the pulpit of stealing a goose.
Read the story →Eratosthenes's famous measurement of the Earth's circumference depended on a peculiar geographical fact about the southern Egyptian town of Syene. On the summer solstice, the Sun stood exactly at the zenith there — a single annual moment that defined the line we now call the Tropic of Cancer.
Read the story →Filippo Pacini examined the intestinal tissue of cholera victims in Florence in 1854 — the same year [John Snow](/articles/john-snow-broad-street-pump) was mapping the Broad Street pump — and identified a comma-shaped bacterium he called *Vibrio cholerae*. The discovery was published in Italian, in an Italian journal, and was almost entirely ignored. [Robert Koch](/articles/robert-koch-cholera-1883) rediscovered the same organism in Egypt in 1883 and got the credit.
Read the story →When the Bourbon-era treasure hunters were finished with Pompeii, the site was a substantially-mined ruin without a coherent excavation record. Giuseppe Fiorelli took over the directorship in 1863 and turned the site into the founding example of modern archaeological method. His most-famous innovation was to pour liquid plaster into the empty voids left by [Vesuvius's victims](/articles/vesuvius-pompeii-79).
Read the story →Konrad of Megenberg was a Regensburg canon and natural-philosophy writer who composed a tract in 1350 explicitly refuting the claim that Jews had caused the Black Death by poisoning wells. He used Aristotelian-medical argument against the popular conspiracy theory that had been justifying the Rhineland pogroms.
Read the story →La Soufrière on Saint Vincent erupted on 6 May 1902 — about thirty hours before Mount Pelée destroyed Saint-Pierre on Martinique. The Soufrière eruption killed approximately 1,500 people across the northern parishes of the island. The simultaneous Pelée catastrophe entirely overshadowed the coverage.
Read the story →Lake Cheko is a 500-metre-wide elliptical lake about 8 km northwest of the Tunguska blast epicentre. In 2007 an Italian research team proposed that the lake is the impact crater of a small unfragmented portion of the 1908 Tunguska body. The interpretation is substantially contested.
Read the story →Leonid Kulik led the first scientific expedition to the Tunguska blast site in 1927, returned four more times in the following thirteen years, and was preparing a sixth expedition when Germany invaded the Soviet Union. He volunteered for the People's Militia in 1941, was captured at Vyazma in October, and died of typhus in a Spas-Demensk POW camp in April 1942.
Read the story →Max von Pettenkofer was the most prominent 19th-century German opponent of the germ theory of cholera. In 1892 he drank a flask of *Vibrio cholerae* sent to him by Robert Koch's institute. He did not die. He shot himself nine years later.
Read the story →Isaac Newton and Gottfried Leibniz independently developed the differential and integral calculus in the 1670s and 1680s. Newton accused Leibniz of plagiarism in 1699. The subsequent thirty-year priority war split the European mathematical community along Newtonian-British and Leibnizian-Continental lines and substantially retarded British mathematics for the next century.
Read the story →Plato's Academy was founded around 387 BC and closed by Justinian's edict in 529 AD. For most of that nine-century period the Academy was the institutional core of Greek mathematical and astronomical teaching — the lineage that produced Eudoxus, Aristotle, Theaetetus, and most of the substantively classical Greek mathematical tradition.
Read the story →A major earthquake struck Pompeii on 5 February 62 AD, doing substantial damage across the city and the neighbouring Vesuvian region. Most of it was still under repair when Vesuvius erupted seventeen years later. Modern volcanology now reads the 62 AD earthquake as the unheeded magmatic-warning sign of the 79 AD catastrophe.
Read the story →Claudius Ptolemy's *Mathēmatikē Syntaxis* — known to Europe as the *Almagest* through its 9th-century Arabic translation — was the single dominant astronomical reference work of the Western world from approximately 150 AD to 1543. Most of its observational content was inherited from Hipparchus of Rhodes three centuries earlier.
Read the story →In May 1818, an expedition led by [Stamford Raffles](/articles/stamford-raffles-singapore) and the surgeon-botanist Joseph Arnold found a 1-metre red flower in the Sumatran rainforest. It weighed about 7 kilograms, smelled of carrion, and had no leaves, stem, or roots. Arnold caught a fever and died on the trip back. The flower was named for both of them.
Read the story →Roger L. Easton Jr. of the Rochester Institute of Technology led the multispectral imaging programme that recovered text from the Archimedes Palimpsest between 1999 and 2008. The technique combines ultraviolet, visible, and infrared photography with substantial computational analysis to detect ink residues invisible to the unaided eye.
Read the story →Christoph Scheiner's *Rosa Ursina sive Sol* (1626–1630) ran to about 780 folio pages, contained the most accurate pre-19th-century star catalogue of the Sun's surface, and devoted hundreds of pages to attacking Galileo's claim to have discovered sunspots first. The priority dispute substantially poisoned the European astronomical mainstream for two decades.
Read the story →The Spörer Minimum was a period of unusually low solar activity that ran from approximately 1450 to 1540. It overlapped with the catastrophic late-medieval collapse of Norse Greenland, the worst phase of the Little Ice Age in central Europe, and the agricultural crisis that preceded the religious upheavals of the Reformation.
Read the story →Thomas Harriot observed the Moon through a telescope in July 1609, sunspots in late 1610, and the moons of Jupiter probably in early 1610. Each of these observations was made independently of Galileo, in some cases earlier. Harriot published nothing. He died in 1621 with about 5,000 pages of unpublished astronomical manuscripts.
Read the story →Thomas Harriot observed sunspots in December 1610 — months before Galileo's published priority claim — telescopically observed the Moon weeks before Galileo's *Sidereus Nuncius*, and worked out the law of refraction twenty years before Snell. He published almost none of it. He died in 1621 of nasal cancer leaving over 8,000 pages of unpublished manuscripts.
Read the story →Robert Koch announced a tuberculosis cure in August 1890 — a glycerol extract from the tuberculosis bacterium that he called *tuberculin*. Within nine months it was substantially clear the substance did not cure tuberculosis and that it had killed several hundred patients. The fiasco nearly destroyed Koch's career.
Read the story →The mural quadrant at Tycho Brahe's Uraniborg observatory was a brass arc mounted on a north-south wall and used for measuring the meridian altitudes of stars and planets. It was the largest and most accurate astronomical instrument of the pre-telescopic period and produced most of the data that Kepler would later use to derive the laws of planetary motion.
Read the story →When [Vesuvius erupted in 79 AD](/articles/vesuvius-pompeii-79), it buried a Roman seaside villa at Herculaneum under 25 metres of pyroclastic debris. Inside the villa was a working library of about 1,800 papyrus scrolls — the only intact classical library that has ever been recovered. The scrolls were carbonised by the heat. Modern X-ray imaging is finally reading them.
Read the story →Alfred Lacroix arrived on Martinique six weeks after the 1902 eruption of Mount Pelée had killed thirty thousand people. He spent the next four years on the island reconstructing exactly what had happened. The science of volcanology, more or less, is what he found.
Read the story →On 15 February 2013 a 20-metre stony asteroid exploded over the southern Russian Urals at an altitude of about 30 kilometres. The blast injured 1,500 people, mostly from flying glass. It was the largest atmospheric impact event since Tunguska in 1908 — and the first to be captured on car-dashboard video.
Read the story →John Snow is remembered for the 1854 Broad Street pump and the founding of modern epidemiology. His other career — as the leading 19th-century English authority on inhaled anaesthesia — is less famous but at the time was substantially more profitable. He gave Queen Victoria chloroform during the births of her eighth and ninth children.
Read the story →Michael Maestlin taught mathematics and astronomy at Tübingen from 1583 to 1631. He was the man who privately taught the young Johannes Kepler that the Copernican heliocentric system was probably correct, while officially continuing to teach the Ptolemaic system that the university curriculum required.
Read the story →In 1257 an Indonesian volcano called Samalas erupted with the largest eruption of the last seven thousand years. The sulphate signal appears in polar ice cores from both Greenland and Antarctica. Medieval European chronicles record the cold summer of 1258. It took until 2013 to identify the source.
Read the story →On the evening of 11 November 1572 a bright new star appeared in the constellation Cassiopeia. It was visible for sixteen months. Tycho Brahe — twenty-five at the time — measured it carefully enough to prove it sat above the Moon. The Aristotelian heavens that were supposed to be unchanging had quietly changed.
Read the story →Uraniborg was the most expensive scientific instrument in 16th-century Europe — an island observatory built for Tycho Brahe at royal expense. He worked there for 20 years, made the most accurate pre-telescope astronomical observations ever, then fled in 1597. The Crown demolished it the next year.
Read the story →Western Electric's Hawthorne Works in Cicero, Illinois, employed 45,000 people at peak. Between 1924 and 1932 a team of Harvard researchers studied the workforce in increasing detail. The eventual finding — that workers behave differently when they know they're being watched — gave its name to the Hawthorne Effect.
Read the story →Hipparchus of Rhodes catalogued a thousand stars, invented trigonometry, discovered the precession of the equinoxes, and may have built the original of the Antikythera mechanism. Almost none of his writing survives.
Read the story →Robert Koch went to Alexandria in 1883 to find the cause of cholera. He found it on the second day and confirmed it in Calcutta four months later. John Snow had been right thirty years earlier without ever seeing the bacterium.
Read the story →In 1610 four astronomers in four countries pointed early telescopes at the Sun and saw spots. They spent the next decade arguing about who had seen them first.
Read the story →Before Eudoxus, Greek mathematicians could prove statements about simple shapes. Eudoxus invented the method that let them prove statements about curves.
Read the story →Henry Whitehead set out to disprove John Snow's water theory. He spent six months knocking on doors in Soho. By the end he had identified the index case.
Read the story →Between 1645 and 1715 the surface of the Sun was nearly blank. Sunspot counts dropped to almost zero. Europe froze. Astronomers noticed, then forgot.
Read the story →After two years of siege, the Romans broke into Syracuse. A junior soldier found a seventy-five-year-old man drawing in the sand and made the worst mistake of his career.
Read the story →He used balance points to discover the volumes of curved solids, then proved them with strict geometry. The Greeks called it forbidden. He called it the Method.
Read the story →Around 240 BC the chief librarian at Alexandria measured the planet's circumference using two shadows and a piece of arithmetic. He was off by about two percent.
Read the story →In November 1577 a comet appeared over Europe so bright it cast shadows. A twenty-eight-year-old Dane measured its distance and demolished Aristotle's heavens.
Read the story →Eight years after Frankenstein, Mary Shelley published a novel about a global pandemic that kills everyone except one narrator. Critics hated it. They had reasons.
Read the story →In 1906 a Danish scholar in Istanbul opened a medieval Greek prayer book and noticed faint mathematics underneath the prayers. It was Archimedes.
Read the story →Hypatia of Alexandria was the most famous philosopher in the eastern Mediterranean. In March 415 a crowd dragged her from her carriage and killed her with roof tiles.
Read the story →In 1620 the seventy-four-year-old mother of Johannes Kepler was arrested for witchcraft. He spent six years getting her out.
Read the story →From around 1300 to 1850 the northern hemisphere ran a few degrees colder. Glaciers advanced, harvests failed, Norse Greenland died, and the Thames repeatedly froze.
Read the story →On 30 June 1908 something exploded above central Siberia with the force of a hydrogen bomb. It took the first scientists nineteen years to reach the site.
Read the story →In December 1566 the 20-year-old Tycho Brahe and his cousin fought in the dark with rapiers over a mathematical disagreement. Tycho lost the bridge of his nose.
Read the story →Sponge divers found a corroded lump of bronze in 1901. It took a hundred and twenty years to admit what it actually was.
Read the story →In September 1854, John Snow walked door to door through Soho with a map, a hypothesis, and a problem the city wouldn't believe.
Read the story →Tambora killed more people than Krakatoa, cooled the planet for two years, and started the Year Without a Summer. The Western press barely noticed.
Read the story →On a Monday morning in August 1883, a volcano in the Sunda Strait made a noise that was registered, four thousand eight hundred kilometers away, as gunfire.
Read the story →Tycho Brahe died because nobody told him he could leave the dinner table. Four centuries later they dug him up to find out for sure.
Read the story →In June 1816 it rained for a month at Lake Geneva. Five English visitors were stuck indoors. One of them was eighteen years old, and she had a dream.
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