Fact check · first aired 1994
Every episode transcribed and checked against what we know today about the history of science. Each point shows the episode, the moment it is said, and the exact line from the English dub (or the original French, where no English upload exists).
Watch the episodes on the official Hello Maestro YouTube channel.
These are the major errors: things a viewer could come away believing that are meaningfully wrong. We also found 138 minor slips (a date, a name or a number slightly off, or a likely dubbing error) which are hidden unless you ask for them.
Outdated: matched what was known at the time, but newer research changed the picture. Common belief then: specialists already knew better, but textbooks and popular books of the day still said it. Wrong in its day: a careful writer could have got it right from ordinary references; often a slip in a number, a name or the dubbing. Plain simplifications for children are not counted; they are listed under each episode. How this was made.
Episode 17 (Louis Pasteur) could not be found in English or French and is not covered.
Maestro opens the series by promising the story of the great discoverers, then spends the episode on early Chinese inventions. He covers row farming and the seed drill, horse harnesses, stirrups, kites and the first man carried by a kite, suspension bridges, the parachute, paper, paper money, printing, movable type and gunpowder. The message is that China was often centuries ahead of Europe. The episode closes on a plea to use inventions for peace rather than war.
"Paper, playing cards, the decimal system, steam engines, the parachute..."
TodayChina never had a steam engine. This claim comes from Robert Temple's popular The Genius of China (1986), which simplified Joseph Needham. Needham argued only that Chinese water-powered bellows (Du Shi, 31 AD) used the same crank-and-connecting-rod layout later used by steam engines. Nothing in China was ever driven by steam. The same list's "hydraulic power, even the steam engine" repeats the error.
Why it was believedTemple's list of Chinese "firsts" was a bestseller and was widely copied in the late 1980s and 1990s. Many items on its list are real, and this one sounded just as solid.
"How blood circulates."
TodayThe Huangdi Neijing (around the 2nd–1st century BC) describes blood and qi flowing in continuous cycles through channels. That is a real and early idea, but it is not circulation in William Harvey's sense (1628): a heart pumping blood out through arteries and back through veins in a closed loop, proved by measurement. Calling it the discovery of circulation 1,000–2,000 years before Europe overstates it.
Why it was believedTemple, following Needham's more cautious wording, presented it as "the circulation of the blood".
"And brandy as well."
TodaySecure evidence of distilled alcohol in China dates only from the Jin and Yuan dynasties (12th–13th century). That is about when distilled "aqua vitae" appears in Salerno and elsewhere in Europe. Earlier Chinese dates are argued but not proven, so China being far ahead on brandy is doubtful.
Why it was believedTemple's book gave an early Chinese date for distilling spirits.
"The same horse could now pull ten times the load."
TodayThe Chinese did develop the breast-strap harness (by about the 4th century BC) and the collar harness (around the 5th century AD) well before Europe. However, the claim that the ancient "throat-and-girth" harness choked horses, and that the collar multiplied pulling power several times over, comes from Richard Lefebvre des Noëttes (1931). Trials by J. Spruytte (1977) and later work showed that the ancient harness, properly fitted, did not choke the horse. The "ten times" figure has no basis.
Why it was believedLefebvre des Noëttes' thesis was taken up by Needham and Lynn White and stayed standard in popular histories of technology.
"The Chinese were 2,000 years ahead."
TodayThe earliest stirrups are Chinese: a single mounting stirrup on a figurine from 302 AD and paired stirrups by about 322 AD. Stirrups reached Europe with the Avars around the 6th–7th century. That is a lead of roughly 300–400 years, not 2,000. India had toe-loop stirrups even earlier. The show is right that the Egyptians, Greeks and Romans rode without stirrups.
"The Chinese stirrup set the stage of history for Western knights in armor."
TodayThis is Lynn White's "stirrup thesis" (1962): stirrups made mounted shock combat possible and so created feudal knighthood. Historians (Sawyer and Hilton 1963, Bachrach 1970 and others) rejected it soon after. Steppe horsemen conquered before they had stirrups, and Frankish adoption of stirrups did not line up with any change in tactics.
Why it was believedWhite's Medieval Technology and Social Change was hugely influential and memorable, and popular books kept repeating it.
"The universal joint that makes car transmissions possible."
TodayThe Chinese device (Ding Huan, about 180 AD) was a gimbal (a "Cardan suspension"), not a universal joint. Gimbals were also known earlier in the Greek world (Philo of Byzantium, 3rd century BC). The universal joint used in drive shafts goes back to Cardano and Robert Hooke (17th century).
Why it was believedTemple's list calls the gimbal a "Cardan suspension", which is easily confused with the cardan (universal) joint.
"This is the story of a young man who became emperor in the Zia dynasty."
TodayThis is the legend of Shun, recorded by Sima Qian (around 90 BC), who escaped from a burning granary by holding two large bamboo hats and jumping. Shun is a legendary ruler, traditionally placed before the Xia dynasty, around 2200 BC (about 4,200 years ago, not "nearly 5,000"). The story is a legend, not evidence that the parachute existed "centuries before our era". ("Zia" is Xia.)
Why it was believedTemple presented it as the first parachute, and popular books repeated it.
"Then you will have the invention of the parachute in Europe, straight from China."
TodayThe European parachute did not come "straight from China". The report that inspired it was Simon de La Loubère's account (1691) of acrobats in Siam (Thailand), not China. It inspired Louis-Sébastien Lenormand, who jumped from a tower in Montpellier in 1783 and coined the word "parachute". André-Jacques Garnerin made the first jump from a balloon on 22 October 1797 over Paris, from about 900–1,000 m. That was a hydrogen balloon, not one of the Montgolfiers'. Faust Vrančić had already published a parachute design in 1595. (The garbled "1080" may be a mishearing of "1680s".)
"It was only in the 13th century that paper was to be made in Europe."
TodayPaper was made in Muslim Spain, at Xàtiva near Valencia, by the mid-12th century, and it was used there earlier. The 13th century is right for Christian Europe (Fabriano in Italy, around 1270s). "15 centuries after China" is about right either way.
"1041, a Chinese Picheng invents movable type, 26 characters in the West, up to 400,000 in China."
TodayBi Sheng ("Picheng") made ceramic movable type in the 1040s, which is correct. But no Chinese printer used 400,000 characters. The largest classical dictionary, the Kangxi Dictionary of 1716, has about 47,000, and a working font needed a few thousand characters (with many copies of each). Wang Zhen's wooden type (about 1300) had around 60,000 pieces. "400,000" is probably a dub or transcription slip for 40,000.
"They were rifles, and mortars, and cannons, incendiary missiles, even flamethrowers."
TodayChina did invent gunpowder weapons: fire lances, bombs, rockets, hand cannons and cannons. Rifling (spiral grooves in the barrel) was a European invention (Germany, late 15th century), so "rifles" is wrong. The Chinese pump flamethrower (919 AD) burned petroleum oil bought from the Arab world, and the Byzantines had been spraying "Greek fire" from siphons since the 670s.
Maestro praises Greek thought: Pythagoras, Hippocrates, Socrates, Phidias, Protagoras, Anaxagoras and Democritus, whose atoms are acted out in a scene. The gnomon then leads to Eratosthenes measuring the Earth from shadows at Syene and Alexandria. Most of the episode follows Archimedes in Syracuse: the golden crown and "Eureka", the screw pump, the ship moved with one hand, the area of the circle, and the Roman siege in which he dies.
"They rose to heights 2,000 years past before there was really anything new."
TodayBetween the Greeks and the Scientific Revolution, science moved forward in the Islamic world (al-Khwarizmi, Ibn al-Haytham, al-Biruni), in India (place-value numerals, zero), in China (as episode 1 itself shows) and in medieval Europe (Oxford calculators, Buridan, Oresme). Historians had long rejected the idea of 2,000 empty years.
Why it was believedThe Renaissance story of a classical golden age, then "dark ages", then rebirth was still standard in popular books.
"Athena, 60 feet high."
TodayPhidias' gold-and-ivory Athena Parthenos was about 11.5–12 m (around 38–40 ft), not 60 ft. His bronze Athena Promachos may have been taller, but estimates for it also fall short of 60 ft.
"the length of the running track used in the olympics 252 000 stadiums that comes to exactly"
TodayEratosthenes' method was sound. He took the angle of the Sun's shadow at Alexandria (about 7.2°, or 1/50 of a circle) when the Sun stood overhead at Syene, and multiplied by the distance between the two cities. But we do not know which stadion he used. The Olympic track is about 192 m, which gives about 48,000 km, roughly 20% too large. The show's "exactly 39,690 km" assumes a stadion of 157.5 m, a disputed modern reconstruction. Estimates for his stadion range from about 157 to 185 m, so his error was somewhere between about 1% and 16%. The 5,000-stadion distance was itself a rough figure, and Syene is not due south of Alexandria. "Only 300 km off" is a choice of number, not a fact.
Why it was believedThe "within 1%" version was popular in textbooks and television (it fits the 157.5 m stadion). Few popular accounts mentioned that the length of the stadion is unknown.
"Alexandria is a peaceful city, and I studied with Euclid, the greatest mathematician in the world."
TodayEuclid was active around 300 BC, and Archimedes was born around 287 BC. If Archimedes studied in Alexandria (Diodorus says he spent time in Egypt), it was with Euclid's successors. His known correspondents there were Conon of Samos, Dositheus and Eratosthenes. Standard references in 1994 already said "probably studied under Euclid's successors".
"Notice the weight of its volume in water that overflowed."
TodayThe bath, "Eureka" and the naked run through the streets come from Vitruvius, writing about 200 years later. The method he describes, comparing the water displaced by the crown with that displaced by an equal weight of gold, would barely have worked. For a 1 kg crown with 30% silver, the extra volume is about 13 cm³, a rise of a fraction of a millimetre in any reasonable vessel. Galileo (La Bilancetta, 1586) suggested that Archimedes more likely weighed the crown against gold while both hung in water, using his own law of buoyancy. The show gives the Vitruvius version as fact.
Why it was believedIt is one of the best-known stories in the history of science, and Vitruvius is an ancient source.
"The blades are turned by the current in the river."
TodayThe Archimedes screw was turned by hand or by people treading it, as in Roman mines and Egyptian fields. It does not run on its own from a river current. No ancient source describes a screw driven by the current, and Vitruvius says men turned it by treading. Diodorus credits Archimedes with the screw during his stay in Egypt. Some historians think it is older still: Stephanie Dalley argued in the 1990s for Sennacherib's Assyria.
"The squaring of the circle."
TodayArchimedes did not square the circle. With compass and straightedge it cannot be done, as Lindemann proved in 1882 when he showed that π is transcendental. In Measurement of a Circle he proved that a circle's area equals a right triangle with the radius and the circumference as its sides. He trapped π between 3 10/71 and 3 1/7 (3.1408–3.1429) using polygons of 96 sides, not between an outer and an inner square. The value 3.1416 is Ptolemy's (377/120), not Archimedes'. That areas of circles go as the square of the radius was already in Euclid (XII.2).
The episode starts with Aristotle's Lyceum and his pupil Alexander, then follows the founding of Alexandria, its lighthouse, its giant ships and the Library's hunt for books. Ctesibius shows off his inventions. The main story pairs Hero and Ptolemy against foolish Roman officials: Hero's steam turbine (aeolipile), his self-opening temple doors and his gear-driven lifting machine (baroulkos), and Ptolemy's maps. It ends with the decline of the Alexandrian school and the destruction of 391.
"Peripatetic. That means everybody walking about because his students weren't stuck sitting in one place."
Today"Peripatetic" most likely comes from the peripatos, the covered walkway of the Lyceum where the school met. The story that Aristotle lectured while walking around is an ancient explanation of the name, not established fact.
Why it was believedThe walking-teacher story is old (Diogenes Laërtius) and appealing, and it was repeated in most popular accounts.
"Ptolemy succeeded Alexander and built a great library and his son Ptolemy II a lighthouse 40 meters high, one of the wonders of the world."
TodayThe Pharos of Alexandria was about 100–130 m high, one of the tallest buildings of the ancient world, not 40 m. It was begun under Ptolemy I and finished under Ptolemy II (around 280 BC).
"Just imagine, the mast was 10 stories high, and there were 2,000 oarsmen."
TodayThe giant "forty" (tessarakonteres) of Ptolemy IV, described by Athenaeus and Plutarch, had 4,000 rowers, plus 400 other crew and about 2,850 marines. The show is right that it was too big to be useful.
"I am working on this invention, an instrument for measuring any differences in heat."
TodayNo thermometer is attributed to Ctesibius ("Sestibus"). Philo of Byzantium and Hero described devices in which warmed air expands and pushes water along. These showed the effect but had no scale and measured nothing. The first scaled thermometers came from Santorio and Galileo's circle around 1600–1612.
"You see, Hero, the Earth's round and the Sun goes around it."
TodayHero and Ptolemy were not contemporaries. Otto Neugebauer (1938) dated Hero by a lunar eclipse in 62 AD, so Hero was active in the mid-1st century. Ptolemy's observations run from 127 to 141 AD, and the Almagest dates to about 150. The friendship is invented, and Hero would have been dead or very old.
"the earth's as flat as a millstone we all know that you've only to look around you"
TodayEducated Romans knew the Earth was a sphere: Cicero (Dream of Scipio), Pliny the Elder, Strabo and Seneca all say so. The show plays Roman officials as flat-earthers for comedy. In fact, Greek and Roman learned culture agreed on a round Earth, and Ptolemy wrote under Roman rule.
Why it was believedThe myth that people before Columbus thought the Earth was flat was spread in the 19th century (Washington Irving, Draper, A. D. White). Historians had exposed it (J. B. Russell, Inventing the Flat Earth, 1991), but it remained common in popular culture.
"It's a bit like a lyre or a harp, but with small hammers that come down upon the strings."
TodayHero did not invent a hammered string instrument. That idea (dulcimer, then clavichord and piano) is medieval and later. Hero's real musical inventions were organs: he described Ctesibius' water organ (hydraulis) and an organ blown by a windmill. Clea and the instrument are fiction.
"Be among the last scientists of the school of Alexandria."
TodayAlexandria went on producing major scholars for three more centuries after Hero: Ptolemy, Diophantus (3rd century), Pappus (4th century), Theon and his daughter Hypatia (died 415), and John Philoponus (6th century).
A quick history of timekeeping. It covers the origins of the week, Egyptian water clocks for night work, the clepsydra used to limit Athenian speeches, unequal "seasonal" hours, hourglasses and Alfred the Great's candle clock. It then tells of Su Song's great astronomical clock and its destruction, the first European mechanical clock, the Dondis' dials and astrarium in Padua, and Galileo's pendulum. It ends with the longitude problem, Harrison's chronometer, wristwatches, quartz and atomic clocks, and asks whether we have mastered time or become its slaves.
"The slaves work from sunup to sunset each day, O'Pharaoh. I don't have enough men."
TodayThe pyramids were built by paid and fed crews of workers, many of them conscripted for a season, not by slaves. The workers' tombs at Giza (found in 1990) and Mark Lehner's excavation of their town show bread, beer and meat rations and medical care. Water clocks are also an anachronism here: the oldest known clepsydra (Karnak, about 1400 BC) is more than a thousand years later than the Giza pyramids. To be fair, the scene's workers are paid in wheat and garlic, which is closer to the truth than its "slaves".
Why it was believedHerodotus, mixing it up with the Hebrew slavery of Exodus, and Hollywood epics made pyramid slaves the default image. The Giza finds were only starting to reach the public in 1994.
"Then we'll all give you an hourglass with sand."
TodayThere is no reliable evidence of sandglasses in Greek or Roman times, or in Charlemagne's day. The first sure depiction is Lorenzetti's fresco in Siena (1338), and sandglasses appear in ships' records in the 14th century. A 12-hour hourglass for Charlemagne is a legend.
Why it was believedOlder clock histories repeated unsourced stories of ancient and Carolingian hourglasses.
"The Byzantine Empire decided to honor the Emperor and present him with a magnificent gift."
TodayThe famous clock given to Charlemagne came from the Abbasid caliph Harun al-Rashid in 807. It was a brass water clock that dropped bronze balls onto a cymbal and had mechanical horsemen, not a Byzantine oil clock. Oil-lamp clocks (glass reservoirs marked with hours) date from about the 17th–18th century.
"Just a few years later, unfortunately, the Song Dynasty was overthrown and replaced,"
TodaySu Song's clock tower was finished in 1088–1094. In 1127, more than 30 years later, the Jurchen Jin took Kaifeng, ending only the Northern Song; the Southern Song lasted until 1279. The Jin moved the clock to their capital at Yanjing (Beijing), but they could not get it working, and it decayed. It was not destroyed on an emperor's order to drive out evil spirits; that scene is invented.
"It's in France that the very first mechanical clock was to be invented."
Today"Brother Gilbert" is Gerbert of Aurillac, a Benedictine who became Pope Sylvester II (died 1003). He did not invent the mechanical clock. The "horologium" he set up at Magdeburg was probably a sundial or a star-sighting instrument. The weight-driven clock with a verge-and-foliot escapement appeared somewhere in Europe around 1270–1300, and its inventor is unknown. The device in the scene, a weight, a drum, cogwheels and a striker with no escapement, would not keep time. Su Song's clock, shown just before, already had an escapement in 1088.
Why it was believedThe Gerbert story appears in many older clock histories and French school books, though historians of horology (Lynn White, Needham, Landes's Revolution in Time, 1983) had dismissed it.
"Came Galileo's pendulum clock and his telescope."
TodayGalileo designed a pendulum clock in 1641, but it was never finished in his lifetime. Christiaan Huygens built the first working pendulum clock in 1656–57. Pendulum clocks did not work on a rolling ship. Galileo's Jupiter-moons method (proposed 1612) worked on land but was impractical at sea, as the scene jokes.
"An error of five minutes means a two-degree error in longitude."
TodayThe Earth turns 360° in 24 hours, so 4 minutes of time equal 1° of longitude. A 5-minute error is 1.25° (about 140 km at the equator). A 2° error needs 8 minutes.
"No real effort was made until a naval tragedy occurred off the English coast on the rocks of the Silly Islands."
TodayThe Scilly wreck of Admiral Shovell's fleet (1707, about 1,400–2,000 dead) did help lead to the Longitude Act of 1714. But "no real effort" before it is wrong. Spain offered a prize from 1567 and again in 1598, which Galileo competed for. The Dutch States General also offered one. The Paris Observatory (1667) and Greenwich Observatory (1675) were founded largely to solve longitude.
"Robert Hooke had already invented the spring-driven clock."
TodaySpring-driven clocks with a coiled mainspring date from the early 15th century. Hooke (around 1658–60) and Huygens (1675) argued over the balance spring, the hairspring that regulates a watch, and the priority dispute is accurately shown. This may be a translation slip for the French spiral.
"the so-called number four, accurate enough to win the Admiralty Prize."
TodayOn its 1761–62 trial H4 was accurate enough to meet the Act's top requirement. But the Board of Longitude never formally awarded Harrison the prize. He received money in stages, and Parliament granted him £8,750 in 1773 after George III intervened, for about £23,000 in total. The prize was set by Parliament and run by the Board of Longitude, not the Admiralty.
Why it was believed"Harrison won the longitude prize" is a natural shortening, used in many popular accounts.
"and the first wristwatches appeared in 1910."
TodayBreguet made a wristwatch for Caroline Murat, Queen of Naples, in 1810–12, and Patek Philippe made one for a Hungarian countess in 1868. Soldiers wore wrist "wristlets" from the 1880s, and Cartier's Santos dates from 1904. Wristwatches became common for men during and after the First World War.
"which is accurate to within one second every 3,000 years,"
TodayThat figure suits caesium clocks of around 1960. By 1994, primary standards such as NIST-7 (1993) were accurate to about 1 second in a million years or better. Today's optical clocks (2010s–2020s) reach about 1 second in 10–30 billion years. (The number could be a dub slip.)
The episode follows Prince Henry of Portugal from the capture of Ceuta (1415) to his "research centre" at Sagres, where caravels are designed, maps are improved and Gil Eanes finally rounds Cape Bojador (1434). It covers the first Portuguese slave trading, the push down the African coast, and ends with Bartolomeu Dias rounding the Cape of Good Hope (1488) and a quick list of the voyages that followed. The lesson is that organised, patient exploration beat fear and superstition.
"And at Sagres, on the southwestern tip of Portugal, Henry will have a genuine research institute built,"
TodayThere was no "School of Sagres" with resident astronomers, cartographers and shipwrights. Henry did have a household at Sagres (Vila do Infante, from the 1440s) and employed a few experts, such as the Majorcan "Mestre Jácome". But no source describes an institute, and most of the early voyages were planned from Lagos and Lisbon. The episode's closing line repeats the idea.
Why it was believedThe idea grew from a 1625 remark by Samuel Purchas and 19th-century nationalist histories. Historians such as Duarte Leite and later Peter Russell ("Prince Henry the Navigator: the rise and fall of a culture hero", 1984) took it apart, but popular books kept it.
"The rudder was my idea."
TodayNo one person designed the caravel at Henry's court. It developed from existing Portuguese and Andalusian fishing and coasting boats. The lateen sail came from the Mediterranean and Arab world, and Europe had used the sternpost rudder since about 1200. The early exploration caravels were small two-masted lateen ships (caravela latina). Three-masted and square-rigged versions came later in the century. Lateen rig lets a ship sail closer to the wind, not straight into it.
Why it was believedPopular histories gave the caravel to the Sagres "school" together with everything else.
"Look, here is the well-known Catalan Atlas drawn by your father."
TodayThe Catalan Atlas (about 1375) is credited to Abraham Cresques of Majorca, and his son Jehuda Cresques was a cartographer. However, the claim that Jehuda ran Henry's map-making comes from identifying him with the "Mestre Jácome of Majorca" mentioned by Duarte Pacheco Pereira. That is a guess, not a documented fact. Jehuda had in fact converted in 1391 and lived as Jaume Ribes in Barcelona.
Why it was believedThe identification was repeated as fact in 19th- and 20th-century popular accounts of Sagres.
"All the Jews were chased from Spain."
TodaySpain expelled its Jews in 1492, more than 30 years after Henry died (1460). In Henry's time the relevant events were the 1391 pogroms in Castile, Aragon and Majorca, which forced many conversions, including that of the Cresques family.
"I sailed in closer despite the terrible heat and saw the ocean falling into a bottomless pit."
TodayThe fears Zurara records for Bojador were real but practical, plus one learned idea. Sailors feared shoals, strong currents and winds that might stop them getting back. Scholars held the old idea that the torrid zone was too hot to live in and would burn men black. Educated Europeans knew the Earth was round, and "falling off the edge" is largely a 19th-century invention (see Jeffrey Burton Russell, Inventing the Flat Earth, 1991). Here the pit is a liar's tale, which the episode exposes, so this is mild.
Why it was believedWashington Irving and others made "medieval flat-earth fears" a standard part of the exploration story.
"Henry of Portugal is trying to sail around the African continent to find a route to the Orient."
TodayHenry's recorded aims, as given by his chronicler Zurara, were to learn what lay beyond Bojador, open trade (especially Guinea gold), find Christian allies such as Prester John, fight Islam and convert people. Sailing round Africa to India became Portuguese policy only under João II, in the 1480s. The Venetian plot to stop Henry is fiction built on this anachronism.
Why it was believedLooking back from Vasco da Gama, older histories gave Henry the India plan.
"Stars on the horizon."
TodayIn the 1430s Portuguese pilots sailed by compass, dead reckoning and coastal landmarks. The first recorded Portuguese latitude reading from the stars with a quadrant is Diogo Gomes's, around 1460. Eanes would not have worked out that he was "on the same latitude as Cape Bojador" from the stars.
Why it was believedPopular accounts credited Henry's "school" with astronomical navigation from the start.
"Well, Henry did discourage it. He opposed it, but..."
TodayHenry ran the early Portuguese slave trade and profited from it. He held the monopoly on Guinea voyages and took the royal fifth. Zurara describes him on horseback at the first big slave sale at Lagos in 1444, taking his 46 captives. The episode's "he opposed it" has no source.
"Anyway, the church hasn't yet decided whether these creatures are human,"
TodayThe Church never debated whether Africans had souls. The idea of a "debate about souls" is a myth that partly garbles the 1550 Valladolid debate about Native Americans, which was about how they should be treated, not whether they had souls. What the papacy did was authorise Portuguese enslavement in the bulls Dum Diversas (1452) and Romanus Pontifex (1455).
Why it was believed"Did they have souls?" was a common shorthand for colonial racism in popular history.
"But most valuable, you will have a map with complete details concerning Africa and the Indian Ocean."
TodayBefore Dias, no Portuguese map showed southern Africa or the Indian Ocean in detail. Finding them out was the point of his voyage. In 1487 João II sent Pêro da Covilhã overland at the same time to gather information on the Indian Ocean. Henry had been dead 27 years and his captains had only reached Sierra Leone.
"1499, Vasco de Gama sails to Calcutta in India."
TodayDa Gama reached Calicut (Kozhikode), not Calcutta, in May 1498. He returned to Lisbon in 1499.
The episode traces writing from Sumer, Egypt and China, then shows Chinese bamboo books, the invention of paper (in a wasp's-nest legend) and Bi Sheng's movable clay type. It then follows Gutenberg as he moves from wooden blocks to cast metal type and a screw press borrowed from the wine press. It ends with Fust's loans and the lawsuit that cost Gutenberg his workshop. The lesson is that inventions build on earlier ones and that printing made books available to everyone.
"Around the same time, the Egyptians invented hieroglyphics, a sacred script, and almost"
TodayEgypt (about 3200 BCE) is right, but the "almost at the same time, the Chinese" that follows is not. The earliest Chinese writing, on Shang oracle bones, dates to about 1250 BCE, some 2,000 years after Sumer. Older Neolithic signs are not accepted as writing.
"and look i just invented paper quickly ink"
TodayPaper was not invented in one moment by Cai Lun (the official in this scene, whose name the transcript garbles) in 105 CE. Archaeologists had found older hemp paper from the Western Han dynasty (2nd–1st century BCE) at Baqiao (1957) and Fangmatan (1986). Cai Lun is now seen as the man who improved paper-making and presented it to the court. The wasp's-nest inspiration is a later legend.
Why it was believedChinese official history (the Hou Hanshu) gives Cai Lun the credit, and Western popular books repeated it.
"And yes, Bang was right. It would take another 1,000 years for printing to"
TodayBi Sheng ("Bang") made movable clay type around 1040 (described by Shen Kuo). That was about 400 years before Gutenberg, not 1,000. Even Chinese woodblock printing (7th–8th century) was only about 700 years earlier. Korea was printing with cast metal type by the 13th–14th centuries (the Jikji, 1377). The scene is also confused: Bi Sheng's type was carved from clay and fired, not made by pressing clay onto a master character.
"selling your poor man's bible for? Half a florin."
TodayWoodcut "block books" such as the Biblia pauperum do not predate Gutenberg. Allan Stevenson's watermark studies in the 1960s dated surviving block books to about 1450–1470 and later, so they were made at the same time as type printing or after it, not before. Single-sheet woodcuts did exist before Gutenberg.
Why it was believedThe neat sequence "block books first, then movable type" was the standard story in older histories of printing.
"I am from Mayo's. I have come to see you on behalf of Johan Fust. He is my father-in-law."
TodayPeter Schöffer came from Gernsheim and had been a scribe in Paris. He married Fust's daughter Christina years later, in the 1460s. Gutenberg had moved back to Mainz by 1448 on his own, so Schöffer did not fetch him from Strasbourg.
"I would need 8,000 florins. 8,000?"
TodayFust lent 800 guilders in 1450 and another 800 in about 1452, both at 6%. In 1455 he sued for 2,026 guilders including interest. The episode's 8,000 + 8,000 = 16,000 is ten times too high, possibly a translation error. The 6% interest is right.
"We will buy the paper in England"
TodayThe paper for the Gutenberg Bible was Italian, from Piedmont: watermarks show a bull's head and a bunch of grapes. England had no paper mill until John Tate's, in about 1490.
"And so, as a result, the court of justice sentences you to the confiscation of all your"
TodayThe only record of the 1455 case is the Helmasperger Notarial Instrument, which records Gutenberg's oath and part of the judgment. It is not known exactly what Fust took. Most historians think Fust gained the Bible type and equipment as security. Gutenberg seems to have kept a workshop and gone on printing, and in 1465 the Archbishop of Mainz gave him a court post and pension. He was not left penniless and thrown out.
Why it was believed"Genius robbed by his financier" is the usual romantic version of the story.
The episode follows Leonardo from his training under Verrocchio in Florence to Ludovico Sforza's Milan. It shows his famous letter offering military engineering, the giant bronze horse that was never cast, the ideal city drawn after the plague, the Last Supper, and the French invasion that ended Ludovico's rule. A fast montage then covers Isabella d'Este, Cesare Borgia, the Mona Lisa and his death in France in 1519. The lesson is Leonardo as the universal mind who was too far ahead of his time and too curious to finish things.
No major errors in this episode. 3 minor slips hidden.
"taken as an apprentice in the workshop of a great artist by the talent of his young apprentice he"
TodayVasari's story is that Verrocchio "never painted again" after seeing Leonardo's angel in the Baptism of Christ. Art historians treat it as a legend: Verrocchio's workshop went on producing paintings, and Verrocchio had always been mainly a sculptor. The painted-shield (rotella) story told just before this also comes only from Vasari.
Why it was believedVasari's Lives (1550/1568) was for centuries the main source for Leonardo's youth, and its anecdotes passed straight into popular biography.
"Salai, what have you done with my drawings for the bicycle?"
TodayThe "Leonardo bicycle" sketch in the Codex Atlanticus was first reported in 1974, after the codex was restored. In 1994 it was still widely accepted, with Augusto Marinoni attributing it to a pupil (Salaì) copying a lost Leonardo design. That is clearly where the episode's Salai joke comes from. In 1997–98 Hans-Erhard Lessing and others showed that the sketch was a modern addition made after the restoration, and most historians now reject it. Leonardo did draw chain drives, but never a bicycle.
"He sent it to his brother-in-law, Deste, to cast cannons."
TodayIn November 1494 Ludovico sent the roughly 70 tonnes of bronze set aside for the horse to Ercole d'Este of Ferrara to be made into cannon. Ercole was Ludovico's father-in-law (Ludovico had married Ercole's daughter Beatrice), not his brother-in-law. Ercole's son Alfonso was the brother-in-law.
The episode runs from prehistoric trepanation through acupuncture, Babylon and Egypt to Hippocrates on Kos, with clinical observation, the four humours and the Oath, and to Galen treating Marcus Aurelius. It moves through the Black Death and Renaissance anatomy to its main story: Ambroise Paré, a poor boy who becomes a barber-surgeon, replaces boiling oil with a gentle ointment, ties off arteries instead of cauterising them and becomes royal surgeon. It ends with Harvey's discovery of the circulation and the Paris faculty's mockery of it. The lesson is that observation and testing beat book learning and the authority of the Latin-speaking elite.
No major errors in this episode. 5 minor slips hidden.
"He founded a hospital and medical school on the island of Koz."
TodayKos already had a medical tradition (the Asclepiad families) before Hippocrates. He did not found it. Its famous Asklepieion sanctuary was built mostly after his death, and Greece had no hospitals in the modern sense. The roughly 60 treatises of the "Hippocratic Corpus" were written by many authors over about a century. It is uncertain which, if any, Hippocrates wrote himself.
Why it was believedHippocrates as the founder of everything is a tradition going back to antiquity, and textbooks repeated it.
"Right down to our own day, 25 centuries later, all doctors take the Hippocratic Oath."
TodayThe Oath probably does not come from Hippocrates himself (Ludwig Edelstein argued for a later, Pythagorean-influenced origin in 1943). Swearing an oath at graduation became widespread only in the 20th century. Most doctors take modern versions such as the 1948 Declaration of Geneva, and many do not swear the original at all. The original bans surgery, abortion and euthanasia and swears by Apollo.
Why it was believed"All doctors take the Hippocratic Oath" was, and is, a common saying.
"Not necessary. I know what you have and what you need to get well."
TodayGalen's own account (On Prognosis) says the opposite. The court doctors thought Marcus Aurelius had a fever. Galen took his pulse, found it normal, and diagnosed an upset stomach from that. The rest of the scene follows Galen closely: peppered wine is what he would give an ordinary man, he put a warm wool compress (with spikenard) on the emperor's stomach, and the emperor took the peppered wine anyway.
"In his studies, he discovered the nervous system and the brain, which he thought was the seat of the soul."
TodayHerophilus and Erasistratus in Alexandria (3rd century BCE) had already described the nerves and the brain's role. Galen's achievement was to prove by animal experiments (cutting the recurrent laryngeal nerve and the spinal cord) that the brain, not the heart, controls voice and movement. His view of the liver as the organ that makes blood is described correctly.
"A million pilgrims on their way to Rome were to die."
TodayNo source supports a million pilgrim deaths. Chroniclers boasted that over a million pilgrims attended the 1350 Jubilee (an exaggeration), and the plague had largely passed by then. Deaths from the whole Black Death (1347–51) are estimated at a third to a half of Europe's population, about 25–50 million.
The episode follows Galileo from his childhood in Pisa through the swinging-lamp pendulum, his falling-body and inclined-plane experiments, his professorships at Pisa and Padua, the telescope and his discoveries in the sky, and his trial and abjuration before the Inquisition in 1633. It teaches that experiment and mathematics, not authority, decide how nature works, and that Galileo paid a price for saying the Earth moves.
"Yes, but still, it moves."
TodayNo record from 1633 has Galileo saying "Eppur si muove" at his abjuration. It would have been a dangerous thing to say in front of the Inquisition. The phrase first appears in print in Giuseppe Baretti's Italian Library (1757). A Spanish painting from about the 1640s, found in 1911, carries the words, which suggests the legend circulated soon after his death. The episode frames its opening and closing around the line as if Galileo really said it.
Why it was believedIt is one of the most quoted lines in the history of science and appears in nearly every popular biography.
"Yes, they thought the sun and all the planets revolved around the earth and had always done so, and God help anybody who didn't agree."
TodayBefore 1616 the Church did not persecute Copernicans. Copernicus dedicated his book (1543) to Pope Paul III, and it was read and taught for 70 years. Jesuit astronomers at the Collegio Romano confirmed Galileo's telescope discoveries and honoured him in 1611. Trouble began only with the 1616 decree, and Galileo's 1633 trial was shaped by politics, his own provocations, and the alleged breach of the 1616 injunction. The show partly concedes this through the Pope's support and the Spanish pressure scene, but its framing is the simple "science versus Church" story.
Why it was believedThe "conflict thesis" of Draper and White (1870s–1890s) was still how most popular books told the story.
"A few years later, Galileo at 14 was admitted to the University of Pisa to begin his medical studies."
TodayGalileo enrolled at Pisa to study medicine in 1581, at 17. Around 14 he was a pupil at the Vallombrosa monastery.
"Galileo went on to use his invention in making clocks."
TodayGalileo only designed a pendulum clock, in 1641–42 when he was blind, and dictated the design to his son Vincenzo. It was never finished in his lifetime. Christiaan Huygens built the first working pendulum clock in 1656–57.
"The speed of a falling body increases by the square of the time it falls."
TodayIt is the distance fallen that grows with the square of the time. Speed grows in simple proportion to time. Galileo's inclined-plane law (published 1638) says the distances are as the squares of the times, i.e. 1, 4, 9, 16. The bells scene shows the right idea, since the bells are spaced so they ring at equal times, but the stated law is wrong.
"Marcantonio, we're going to create a device that will make distant objects appear much closer."
TodayGalileo did not invent the telescope. Spectacle-makers in the Netherlands made the first ones; Hans Lipperhey applied for a patent in October 1608. Galileo heard of the device in 1609, worked out how it worked, and quickly built much better ones (about 8x, then about 20x). His real achievement was turning it on the sky and publishing what he saw (Sidereus Nuncius, 1610). The episode never mentions the Dutch and has him present it to the Doge as "this invention".
Why it was believedGalileo was the first to make the telescope famous, so popular accounts often credit him with inventing it.
"don't forget my young friend only 10 years ago giordano bruno said the earth revolved"
TodayBruno was burned in Rome in 1600, about ten years earlier, so the date is right. But his condemnation rested mainly on theological charges: denying the Trinity, the divinity of Christ and transubstantiation, plus pantheism and an infinity of inhabited worlds. Copernicanism was a small part of it at most. Historians since Frances Yates (1964) have stressed this. He was not a martyr for heliocentric astronomy.
Why it was believedNineteenth-century anticlerical writers made Bruno a martyr of science, and popular books kept that image.
"with a salary of a thousand thorns per month."
TodayIn 1609 the Venetian Senate gave Galileo a life appointment at Padua with his salary raised to 1,000 florins a year, not a month. "Thorns" is a mishearing of "florins".
"Jupiter clear as day with its two little moons."
TodayGalileo found four moons of Jupiter in January 1610 (Io, Europa, Ganymede and Callisto, which he called the Medicean stars). On the first night he saw three "stars" beside the planet, and by 13 January he had seen all four. "Two" matches none of his records.
"These sunspots, they're not where they were a few days ago. It proves we are moving around the sun."
TodayThe steady drift of sunspots across the disc shows that the Sun rotates (about once a month). It does not show that the Earth orbits the Sun. Galileo's sunspot letters (1613) argued that the spots were on the Sun, so the heavens were not perfect and unchanging. Only later, in the Dialogue, did he argue that the yearly change in the spots' paths favoured Copernicus, and even that was not a proof.
"So, according to my observations, the sun does not move around the earth, it's the contrary."
TodayGalileo had strong arguments but no proof. The phases of Venus (1610) ruled out Ptolemy's system, but they fitted Tycho Brahe's system, in which the Sun circles the Earth, just as well. The proof Galileo himself offered in the Dialogue was his theory of the tides (mentioned at the trial: "only the seas are influenced by this astounding speed"), and that theory was wrong. Direct evidence that the Earth moves came with Bradley's stellar aberration (1729) and Bessel's stellar parallax (1838). Bellarmine's demand for a real demonstration was not unreasonable for its time.
Why it was believedPopular history treated Galileo as the man who proved Copernicus right, and the Church as rejecting proof he already had.
"The worthy head of the Society of Jesus, Cardinal Gaspard Borgia"
TodayCardinal Gaspar de Borja y Velasco was Spain's ambassador and did protest in the consistory of March 1632 that Urban VIII was soft on the Protestants, which put pressure on the Pope just as the Dialogue appeared. But he was not head of the Jesuits. The Jesuit Superior General was Muzio Vitelleschi.
The episode follows Isaac Newton from a farm boy making water clocks, through Cambridge, the plague years at Woolsthorpe (prism experiments and the falling apple), his laws of motion and universal gravitation, Halley's push to publish, the quarrels with Hooke and Leibniz, and his later life at the Mint and the Royal Society. It teaches that gravity holds the Moon and planets in orbit and that Newton's mechanics still underpins modern technology.
"do you realize children that astronauts are floating in space millions of miles over our head right now"
TodayIn 1994 astronauts (the Space Shuttle, Mir) orbited about 300–400 km up, a few hundred miles. Only the Apollo crews ever went farther, to the Moon about 384,000 km (240,000 miles) away. Communications satellites sit about 36,000 km up. "Millions of miles" is far off.
"The apple fell on me."
TodayThe apple story is genuine in that Newton told it himself in old age (to William Stukeley and John Conduitt, 1726). He said that seeing an apple fall at Woolsthorpe set him thinking about gravity reaching to the Moon. The apple hitting his head is a later embellishment. Here it falls on his sister rather than on Newton, but the scene is the same legend.
Why it was believedThe bonk-on-the-head version is a staple of cartoons and children's books.
"So it must have an acceleration 3,600 times greater than that of the apple."
TodayIt is the reverse. The Moon is about 60 Earth radii away, so by the inverse-square law its acceleration toward the Earth is 3,600 times smaller than the apple's: about 2.7 mm/s² against 9.8 m/s². That match was the whole point of Newton's Moon test. The numbers given just before (6,400 km, 380,000 km, factor 60) are right.
"If only I could measure the Earth's radius, precisely."
TodayThe old story says Newton's Moon test failed in 1666 because he used a poor figure for the Earth's size, so he shelved gravity for 20 years until Picard's measurement (1669–71). Florian Cajori (1928) and later Newton scholars (I. Bernard Cohen, Richard Westfall, 1980) showed this is doubtful. In 1666 Newton did not yet have universal gravitation, or the proof that a sphere attracts as if all its mass were at its centre. Both came in 1684–87, after Halley's visit. The episode repeats both the radius-delay story and the "all worked out in the plague year" story ("He's already made most of his great discoveries").
Why it was believedNewton's own late recollections encouraged the "annus mirabilis" legend, and popular books repeated it.
"Before Newton, nobody had ever realized that it's because of centrifugal force that the moon doesn't fall to earth."
TodayNewton's insight was the opposite: no outward force holds the Moon up. Seen from outside, only gravity acts on the Moon. It keeps "falling" toward the Earth, but its sideways motion (inertia) means it keeps missing, as the episode's own cannonball example later shows. "Centrifugal force balances gravity" only describes things from a rotating frame. In any case the idea was not new with Newton: Huygens worked out centrifugal force around 1659 (published 1673), and Borelli (1666) and Hooke (1679) described orbits as a balance between a pull toward the centre and the tendency to fly off.
"Saturn is a hundred times larger than the Earth. You'd feel heavier, so heavier."
TodaySaturn has about 95 times the Earth's mass, but its radius is about 9.5 times larger, so gravity at its cloud tops is only about 1.07 times Earth's. You would barely feel heavier. (A child says this line, but the episode lets it stand.)
"Almost none of our great discoverers were recognized by the contemporaries."
TodayNewton is a counter-example: he became Lucasian professor at 26, president of the Royal Society, Master of the Mint and a knight, and he received a state funeral in Westminster Abbey. Critics like Huygens and Leibniz objected to particular ideas (action at a distance), as the episode shows, but they admired his work.
Why it was believedThe "misunderstood genius" story is a standard theme of popular history of science.
"So, my young friend, you have discovered a comet."
TodayHalley did not discover the 1682 comet that bears his name. Many astronomers saw it, and the Great Comet of 1680 was first found by Gottfried Kirch. Halley was already a Fellow of the Royal Society known for his southern star catalogue, not a novice. What prompted the Principia was Halley's visit to Newton in August 1684 with the question of what orbit an inverse-square force produces. Halley used Newton's theory to show that the comets of 1531, 1607 and 1682 were one object only in 1705, after the Principia was published, and he predicted its return in 1758.
The episode asks how old the Earth is. It contrasts Archbishop Ussher's biblical date and other theories based on the Flood with Buffon's work: his needle probability problem, his burning mirrors, his theory of a comet striking the Sun, his censure by the Sorbonne, and his cooling iron balls that gave an age of about 75,000 years. A "time machine" then visits the early Earth, the Carboniferous, the break-up of the continents and the end of the dinosaurs. It teaches that the Earth is about 4.5 billion years old and that Buffon pioneered a scientific history of the Earth.
No major errors in this episode. 5 minor slips hidden.
"Well, it was 4,004 years B.C., the 29th of October."
TodayUssher (1650) dated Creation to the nightfall before Sunday 23 October 4004 BC. The "9 o'clock in the morning" comes from John Lightfoot of Cambridge (1644), who meant something different: the creation of man, at the autumn equinox. The two were merged in popular retellings. ("29th" may be a dub or transcription slip.)
Why it was believedThe merged "23 October 4004 BC at 9 a.m." version was widely repeated in popular books and textbooks.
"No one, not even the scientists, could yet comprehend that the sacred book, the Bible, spoke in symbols and that religion and science need not be antagonistic."
TodayReading Genesis non-literally is very old: Augustine (De Genesi ad litteram, around 415) warned against using Scripture to contradict what is known about nature. Galileo argued the same (episode 9). Burnet and Whiston themselves treated parts of Genesis as figurative. The line, and the closing "The study was finally getting to replace theology", follows the science-versus-religion "conflict" story.
Why it was believedThe Draper–White conflict narrative dominated popular history of science.
"Nobody since Aristotle the Greek 2,000 years earlier had attempted that."
TodayPliny the Elder's 37-book Natural History (AD 77) is the obvious counter-example. Renaissance encyclopedists such as Conrad Gesner and Ulisse Aldrovandi also attempted complete natural histories.
"This would be the first time a scientist asserted that the Earth had not been created in six days"
TodayBuffon's 1778 figure was the first age estimated by experiment, which is the fair claim. Others had already rejected the six days and the 6,000 years. Benoît de Maillet's Telliamed (written in the 1720s, published 1748) gave an age of about two billion years. Descartes and Leibniz described a long natural cooling of the Earth, and Buffon himself had said "much more than 6,000 years" in 1749.
Why it was believedBuffon was the best-known early figure, and popular accounts made him "the first".
"Yes, he's the one, he gets all the glory for all our modern biology, Buffon."
TodayBuffon was a major figure, but this overstates his role. He mostly held species to be fixed, with "degeneration" within a family (e.g. pig and boar), and he explicitly rejected common descent of all animals in 1753, though he toyed with the idea. Evolutionary theory owes much more to Lamarck (1809), Darwin and Wallace (1858–59). Linnaeus's classification also shaped modern biology. Jacques Roger (Buffon, 1989) gives the balanced view.
Why it was believedOlder histories, e.g. in A. O. Lovejoy's Forerunners of Darwin (1959), cast Buffon as a forerunner of Darwin.
The episode follows Antoine Lavoisier from his prize for street lighting and his water-into-earth experiment, through his marriage to Marie-Anne Paulze, the discovery of oxygen and the overthrow of phlogiston, the ice calorimeter with Laplace, the synthesis of water and the metric system, to his execution as a former tax farmer in 1794. It teaches conservation of mass, the role of oxygen in burning and breathing, that water is a compound, and that knowledge must come from experiment.
"Nothing is destroyed, nothing is created, only transformed."
TodayThe slogan is a later paraphrase. Lavoisier wrote in the Traité élémentaire de chimie (1789) that nothing is created in operations of art or nature, and that the amount of matter is the same before and after. The idea of conservation was also much older (ancient Greeks; Lomonosov, 1748–56). It also does not follow from the 1768–69 water experiment as the episode suggests; that showed the "earth" came from the glass.
Why it was believed"Rien ne se perd, rien ne se crée, tout se transforme" is taught in French schools as Lavoisier's own words.
"Gentlemen, whenever we heat calcinate of mercury, we obtain a quite special gas. Which we call oxygen."
TodayPriestley (1774) called the gas "dephlogisticated air" and defended phlogiston until his death in 1804. Lavoisier coined "oxygène" (1777). Carl Wilhelm Scheele had isolated the gas first ("fire air", about 1771–72), and the episode omits him. Priestley's account in Paris in October 1774 was given at a dinner with Lavoisier, not at the Academy.
"Your potassium chlorate might replace the saltpeter that we're lacking."
TodayPotassium chlorate was Claude-Louis Berthollet's discovery (1786–87), not Lavoisier's. Lavoisier ran the Gunpowder Administration from 1775 and mainly improved saltpetre production. The 1788 trial of chlorate powder at the Essonnes mill exploded and killed two people while Lavoisier and his wife were nearby.
"Air is composed of at least three different gases."
TodayLavoisier's air was oxygen ("vital air") and nitrogen (his "azote"). Hydrogen is not a component of air in any real amount. The episode adds it to the list. (Argon, about 1% of air, was found in 1894.)
"the republic has no more need of chemists or of scientists"
TodayThe famous "La République n'a pas besoin de savants" is not in any record of the trial. It first appears years later and is usually given to the tribunal's president, Coffinhal, not to Fouquier-Tinville. Denis Duveen (1954) and later historians traced it to legend. Lavoisier was condemned, with 27 other tax farmers including his father-in-law, on charges about the Ferme générale, not for being a scientist.
Why it was believedThe line is repeated in almost every popular account of Lavoisier's death.
The episode traces steam power from Hero of Alexandria's useless toy through Denis Papin's pressure cooker, Newcomen's mine engine, Watt's more efficient engine, Cugnot's road carriage and Murdoch's model, to the first locomotives. It then follows George Stephenson and his son Robert from the Killingworth colliery engines to Locomotion, the Liverpool and Manchester route and the 1829 Rainhill trials, and ends on modern 300 km/h trains.
No major errors in this episode. 4 minor slips hidden.
"And so it was, children, that that was all that Denis Papin left us, the pressure cooker, but things would change."
TodayPapin's steam digester (1679), the forerunner of the pressure cooker, came before his engine work, not after it, and he invented the safety valve for it. In 1690 he described the first steam cylinder with a piston, worked by condensing steam, which is the principle Newcomen's engine later used. He also built a paddle boat (1707). So the pressure cooker was far from all he left, and the French show undersells its own inventor.
"I would prefer you take it in through the door, sir, and not through the wall."
TodayCugnot's steam fardier (1769–71), built to haul artillery, is real. The story that it ran out of control and knocked down a wall of the Paris Arsenal is not in contemporary records. It first appears decades later, and historians treat it as a legend.
Why it was believedThe "first car, first car crash" anecdote has been repeated in French popular histories and motoring books since the 19th century.
"It's not a toy, it's a scale model of the very first locomotive on rails."
TodayWilliam Murdoch's model of about 1784 was a steam road carriage, not a rail locomotive. The first locomotive to run on rails was Richard Trevithick's, at Penydarren in 1804. Murdoch was also a Scot from Ayrshire, not an Englishman, though "Fire the Englishman" may be a transcription error.
"My opinion, it should be a new design, a boiler with pipes."
TodayThe multi-tubular boiler that made Rocket (1829) work was suggested by Henry Booth, treasurer of the Liverpool and Manchester Railway. Marc Seguin had already patented a fire-tube boiler in France in 1827–28. Rocket itself was designed and built mainly by Robert Stephenson at the Newcastle works. George was the railway's engineer, but he was not the lone inventor of the boiler.
Why it was believedSamuel Smiles's Lives of the Engineers (1857–62) made George Stephenson the single "Father of Railways", and popular books followed him. To its credit, the show does give Robert a real role in running the workshop.
The episode surveys early electricity: lightning, a claim that Moses' Ark of the Covenant was an electrical capacitor, the Chinese compass, Hauksbee, the Leyden jar, Nollet, Franklin, Richmann's death, and Galvani's frogs against Volta's battery. It then follows Michael Faraday from bookbinder's apprentice to Davy's assistant, Ørsted's 1820 discovery, electromagnetic rotation and the first dynamo, and ends with a cartoon of "ions" carrying current and a reflection on fields of force.
"Moses had just invented the condenser,"
TodayThe Maestro presents as fact the idea that the gold-lined Ark of the Covenant was an electrical capacitor and that Moses was "earthed" through golden threads in his robe. This is fringe speculation of the ancient-mysteries kind, with no support in the biblical text or in archaeology. Moses' historicity, and the "3,500 years ago" date, are themselves uncertain. The Exodus account does say the ark was overlaid with gold inside and out.
"Charges on the bottom of these ion elements"
TodayThe explanation of lightning is muddled. It is true that in fair weather the ground is negative and the ionosphere positive (the global atmospheric circuit). But lightning comes from charge separation inside thunderclouds in the troposphere, mainly from collisions between ice and graupel. It is not a discharge from the ionosphere. The troposphere is not "dry air", since it holds nearly all the atmosphere's water vapour. Faraday did not "demonstrate" any of this: the global circuit came from Kelvin and C.T.R. Wilson, and the ionosphere was only named in the 1920s.
"I'm boiling frog broth for Signora."
TodayThe story that Galvani found "animal electricity" because frogs were being prepared as broth for his sick wife (Lucia Galeazzi, whose name the show gives to a servant) is a later legend, first printed by Alibert in 1801. Galvani's own De viribus electricitatis (1791) describes planned laboratory work with frog nerve-muscle preparations. Galvani worked in Bologna; "Cologne" is a mishearing.
Why it was believedThe kitchen anecdote was a favourite in 19th- and 20th-century popular science books.
"but I do not believe the frog stores up a reserve of animal electricity."
TodayVolta was right that two different metals plus a moist conductor produce a current, and this led to his pile (1800). But Galvani was also partly right: nerves and muscles do carry electricity, as Matteucci and du Bois-Reymond showed in the 1840s. Galvani even made a frog leg twitch with no metals at all. The show stages a face-to-face win for Volta. The real dispute was conducted in print, and Galvani died in 1798, before the pile was built.
Why it was believedThe "Galvani wrong, Volta right" story was standard textbook history. Marcello Pera's The Ambiguous Frog (1986, English 1992) had already given a more balanced account.
"I name these ions."
TodayFaraday did coin "ion" (1834, with William Whewell), but for charged particles moving through a solution during electrolysis. An ordinary current in a copper wire is carried by electrons (J.J. Thomson, 1897), and the metal ions stay put. The cartoon of negative and positive "ions" running through a wire as the current is wrong for metals. It describes electrolytes and plasmas, not wires.
"The distance of the moon from the Earth."
TodayLight covers about 300,000 km in a second, but the Moon is about 384,000 km away, so light takes about 1.3 seconds. Also, the charges in a wire drift at fractions of a millimetre per second. Only the electrical signal travels at close to the speed of light.
The episode follows Charles Darwin from failed medical student and beetle collector to naturalist on the Beagle: fossil giant sloths, the rhea, Tierra del Fuego and the Galápagos finches. It covers his marriage to Emma Wedgwood, his long hesitation to publish, Lamarck's giraffe against natural selection, Wallace's independent discovery, the 1859 Origin of Species and the 1860 Oxford debate between Huxley and Wilberforce.
"Now, the Earth was created exactly 6,024 years ago."
TodayAdam Sedgwick was a leading old-Earth geologist. He accepted an Earth far older than the Bible's chronology and publicly gave up even his belief in a universal Flood in 1831. He opposed evolution on religious and moral grounds, not because he believed in a young Earth. The figure doesn't fit Ussher's date either, which in about 1830 gives about 5,830 years.
"Strange. These finches seem to be identical, but their beaks differ."
TodayIn the field Darwin did not recognise the Galápagos finches as one related group. He mislabelled several as wrens or grosbeaks and did not record which island most came from. Their importance became clear only after John Gould classified them in 1837, and Darwin had to borrow FitzRoy's labelled specimens. His real Galápagos clues were the mockingbirds, which differed by island, and the vice-governor's remark that tortoises differed from island to island.
Why it was believedDavid Lack's book Darwin's Finches (1947) and later textbooks made the finches the emblem of Darwin's "eureka". Frank Sulloway's 1982 paper "Darwin and His Finches: The Evolution of a Legend" had already corrected the story.
"Oh, there were to be eight in all."
TodayCharles and Emma Darwin had ten children. Three died young (Mary, Anne and Charles Waring), and seven survived to adulthood.
"A sort of missing link between us and the ape."
TodayDarwin argued that humans and apes share common ancestors, not that humans descend from living apes or monkeys along a single chain with one "missing link". The Origin (1859) barely mentions humans, apart from one line saying that "light will be thrown" on human origins. Human descent came in The Descent of Man (1871).
Why it was believedThe "missing link" was a press and Haeckel-era image of evolution as a ladder, and it remained common in popular culture.
"I can still recall the laughter when I proposed the idea that a bear,"
TodayThe bear-to-whale passage, a bear swimming with its mouth open to catch insects, appeared in the first edition of the Origin (1859). Darwin cut it from later editions after it was mocked. It came after publication, not as an earlier "error of youth" before it.
"Very well, I'll publish, but only the first three volumes."
TodayThe Origin was one volume, which Darwin called an "abstract" of a much longer book (Natural Selection) that he never finished. "Volumes" may be a dubbing error for chapters.
"There can be no dishonor, Mr. Wilberforce, in descending from a monkey."
TodayThe 1860 Oxford meeting took place, and the grandmother question and Huxley's retort are traditional. However, no verbatim record exists, and contemporary accounts disagree about who did best. Many present thought Hooker made the stronger reply. Wilberforce's review, coached by Richard Owen, made scientific objections rather than appealing to Ussher's 6,000 years. Lyell was not present.
Why it was believedThe story of Huxley crushing the bishop was built up later in memoirs and in Leonard Huxley's Life and Letters (1900). J.R. Lucas's article "Wilberforce and Huxley: A Legendary Encounter" (1979) had already taken it apart.
The episode tells Gregor Mendel's life: a poor peasant boy in Silesia and Moravia, then an Augustinian friar in Brno who crossed thousands of pea plants and found dominant and recessive traits. It shows his work being ignored and then rediscovered in 1900, and it races through Morgan, Avery, Watson and Crick, McClintock and the genetic code to genetic engineering. Along the way it explains in simple terms how a recessive trait can disappear in one generation and come back in the next.
No major errors in this episode. 8 minor slips hidden.
"I've observed for 20 years to learn that."
TodayMendel's pea experiments ran from about 1856 to 1863, roughly eight years, and he presented them in February and March 1865. The later line "20 years of research" is wrong for the same reason.
"The little finches that ate leaves had thin beaks to cut them up, and the ones that ate nuts had large beaks to break them."
TodayThis repeats the finch legend (see episode 15): Darwin did not work out beak adaptation in the field. Thin-billed Galápagos finches mostly eat insects and large-billed ground finches crack seeds, so "leaves" and "nuts" are also wrong.
Why it was believedDavid Lack's 1947 book made Darwin's finches the textbook example of adaptation.
"What he discovered was the gene."
TodayMendel spoke of "elements" (Elemente) and characters. He gave statistical rules of inheritance, but he did not clearly describe paired, particle-like "genes" (the show's line "pairs of little particles"). Olby's 1979 paper "Mendel no Mendelian?" questions whether he thought of paired factors at all. The word "gene" dates from Johannsen (1909), and the modern gene concept grew out of 20th-century work.
Why it was believedTextbooks read 20th-century Mendelism back into Mendel's 1866 paper.
"And the peas will have a yellow pod."
TodayThis mixes up two of Mendel's traits. Yellow is dominant for the seed (cotyledon) colour, but for pod colour green is dominant over yellow. A plant with one yellow-seed and one green-seed factor has yellow seeds, not a yellow pod.
"Mendel was too far ahead of his time."
TodayMendel's 1866 paper was printed in a journal sent to over 100 libraries, it was cited a handful of times before 1900 (for example in Focke's 1881 survey), and he corresponded with the botanist Carl Nägeli. Historians such as Robert Olby (1979) and Augustine Brannigan (1979) argue that his work was neglected less because it was "too advanced" than because it was read as a study of plant hybrids, which is mostly what Mendel intended. They also point out that the "rediscovery" story was partly shaped by the 1900 priority disputes.
Why it was believedThe "lonely genius ignored by his time" story came from the 1900 rediscoverers and Iltis's 1924 biography, and it was standard in textbooks.
"These bees here, they produce twice as much honey as the others."
TodayMendel did keep bees and tried to cross local bees with Italian and Cyprian strains. The project largely failed, because queens mate in flight and he could not control the matings, so simply putting males in a hive with a queen doesn't work. One hybrid strain was reportedly so aggressive that it had to be destroyed. No high-yield bee came out of his work.
"It's the genetic code."
Today"Mr. Ocha" is probably Severo Ochoa. His lab did contribute to working out the code, but the decisive work was Marshall Nirenberg and Heinrich Matthaei's 1961 experiment, followed by Nirenberg's and Har Gobind Khorana's groups (Nobel Prize 1968, with Holley). Ochoa's 1959 Nobel was for synthesising RNA. No single person decoded the code.
"Now we've learned that DNA is contained in genes which transmit characteristics."
TodayThis is backwards: genes are stretches of DNA. The episode said so correctly a moment earlier ("genes are made of DNA"), so this may be a dubbing slip.
Maestro plays an early phonograph and tells Edison's life story. It starts with the curious boy in Port Huron and his home schooling, then covers his years as a newsboy and telegraph operator, the vote counter and stock-ticker sales, Menlo Park, the phonograph, the light bulb and Pearl Street, and the film studio. The lesson is that Edison was less a scientist than an inventor who turned science into everyday devices.
No major errors in this episode. 4 minor slips hidden.
"When you add water, it gives off hydrogen."
TodayIn Edison's own story he gave his friend Michael Oates Seidlitz powders. These are sodium bicarbonate and tartaric acid, and with water they give off carbon dioxide, which is heavier than air. No powder a boy would have had gives off hydrogen in water, so the chemistry is off even though the anecdote is real.
"battle that'll decide the war general grant against general johnson"
TodayThis is Shiloh, Grant against Albert Sidney Johnston, fought on 6–7 April 1862, not in 1861 as the narration says just before. It did not decide the war. Edison's trick fits the sources: he telegraphed the headlines ahead to stations and sold about 1,000 papers at higher and higher prices.
"Now, this thread is carbonized."
TodayThe episode presents the incandescent lamp as Edison's alone. In England, Joseph Swan had shown carbon-filament lamps in 1878–79, and the two later merged their British interests as "Ediswan" (1883). Edison's real achievement was a complete system: a high-resistance filament, generators, wiring, meters and a central station. A Menlo Park team built it, including Charles Batchelor, Francis Upton and John Kruesi.
Why it was believedAmerican popular histories told the light bulb as a lone-genius story, and Edison worked hard to promote that version himself.
"but it's Edison who invented it."
TodayWilliam Kennedy Laurie Dickson did most of the work on the Kinetograph camera and Kinetoscope viewer in Edison's lab (1889–92). He built on earlier work by Marey, Muybridge and Le Prince. Gordon Hendricks documented Dickson's role in The Edison Motion Picture Myth (1961). The show does mention the Lumières' projected cinema (1895).
Why it was believedThe patents and publicity carried Edison's name, and popular books repeated "Edison invented the movies".
The episode opens with a quick history of messages: runners, signal fires, smoke signals and Chappe's optical telegraph. It then explains invisible electromagnetic waves through Hertz and follows Marconi from attic experiments in Bologna to England, the Channel link, the 1901 transatlantic signal and the Titanic. It ends with Bell Labs' transistor as the next step in communication.
"It's an Italian, Guglielmo Marconi, who was the first to have the idea."
TodayOthers had the idea of signalling with Hertzian waves before Marconi's 1895 tests, or at the same time. Oliver Lodge sent Morse signals by radio at Oxford in 1894, and Popov, Jagadish Chandra Bose and Tesla were working on it too. Marconi's real contribution was making it work over long distances and selling it, with a grounded high antenna and a better coherer. In 1943 the US Supreme Court struck down key Marconi patent claims because of earlier work by Lodge, Tesla and Stone. The show does credit Branly's coherer and Popov's antenna, which is better than most popular accounts.
Why it was believedMarconi's Nobel Prize (1909, shared with Braun) and his company's publicity made him "the inventor of radio" in popular books.
"Uh, well, the sun's distance is 50 million kilometers."
TodayThe Sun is about 150 million km away. Whisper may have dropped "a hundred and", so this may be a transcription error.
"and the SOS was heard by several ships"
TodaySeveral ships heard the Titanic's CQD/SOS in 1912, but only the Carpathia reached the scene and picked up survivors, about 705–712 of roughly 2,224 people aboard. "One out of three" is right, and "740" is a little high.
The episode goes from the Sumerian wheel through Leonardo's spring cart, Cugnot, Murdoch, Lenoir, Otto, Benz and Daimler to the first fancy cars. It then follows Henry Ford from the farm and the Edison company to the kitchen-sink engine, the Quadricycle, racing, the Selden patent fight, the Model T, the assembly line and the $5 day. The message is that Ford made the car affordable for ordinary people, and gave us traffic jams too.
No major errors in this episode. 6 minor slips hidden.
"This would be the first internal combustion engine, so-called because regular explosions of the air and fuel mixture supplied the power to push the pistons."
TodayOtto's 1876 engine was not the first internal combustion engine. Lenoir's gas engine (1860) came first and was sold commercially, and the episode itself says so later. Otto's real advance was the four-stroke cycle with compression (the principle was patented by Beau de Rochas in 1862). Also, Otto's engine was fired by a gas flame through a slide valve, not by the "electric spark" shown. Lenoir's engine was the one with a spark.
"Your own wedding's something not to miss."
TodayFord married Clara Bryant in April 1888 and joined the Edison Illuminating Company in Detroit in 1891, so he was not working there on his wedding day. A small dramatic shortcut.
"It was a Frenchman, René Lenoir,"
TodayHe was Jean Joseph Étienne Lenoir, born in Luxembourg (then part of the Netherlands) and later a naturalized Frenchman. Earlier the episode calls him "André Lenoir". Either name may be a dub or transcription error.
"The biggest seller in history."
TodayAbout 15 million Model Ts were built (1908–27). The Volkswagen Beetle passed that total in February 1972, so by 1994 the Model T was no longer the best-selling car ever.
"And I propose right now to double the salaries of all our workers."
TodayThe $5 day (January 1914) roughly doubled pay, but it was not mainly generosity. Turnover on the new assembly line ran around 370% a year, and higher pay cut it sharply and raised output. Only workers who passed checks by Ford's Sociological Department got the full rate. Economic historians (Meyer 1981, Raff and Summers 1987) describe it as an efficiency wage. The Dodge brothers' lawsuit (decided in 1919) was about Ford holding back dividends to expand, not about wages.
Why it was believedFord presented the $5 day as profit-sharing, and the "benevolent Ford" story was standard in popular histories.
"In 1927, the Golden Arrow attained 370 kilometers an hour."
TodaySegrave's Golden Arrow set its record of 231 mph (372 km/h) in March 1929. In 1927 Segrave's Sunbeam reached about 328 km/h. The Blue Flame's 1,001 km/h in 1970 is correct.
The episode starts with Icarus and Leonardo, then moves to the Montgolfier balloons, the Channel crossing by Blanchard and Jeffries and a parade of failed 19th-century flying machines. It covers Ader, Lilienthal, Maxim and Chanute, then follows the Wright brothers in detail from the toy helicopter to the gliders, Kitty Hawk, the 1904–05 flights and the 1908 Le Mans demonstrations. It ends with Blériot's Channel crossing, Adrienne Bolland, Lindbergh and the Comet.
No major errors in this episode. 5 minor slips hidden.
"leonardo da vinci did more than anyone to realize that"
TodayLeonardo's notes on flight were not published until the late 19th century, so they influenced nobody who actually built aircraft. The founder of aeronautics was Sir George Cayley. In 1799 he described the modern fixed-wing aircraft, with lift, thrust and control kept separate, and in 1853 his glider carried a person. The episode never mentions him. Giovanni Borelli (1680) was the one who showed that human muscles are too weak for flapping flight.
Why it was believedLeonardo as the prophet of flight was a fixture of popular histories, while Cayley was little known outside Britain.
"alibaba and his flying carpet"
TodayThe flying carpet in the Arabian Nights tradition belongs to Prince Husain in the tale of Prince Ahmed and Pari-Banu, not to Ali Baba, and neither story is Chinese. The transcript is garbled here, so the dub may have listed China (kites) separately.
"The Montgolfier brothers made a balloon, and they went off in free flight."
TodayThe Montgolfiers built the balloon, but the first crewed free flight (21 November 1783) carried Pilâtre de Rozier and the Marquis d'Arlandes. Joseph Montgolfier flew only once, in 1784, and Étienne never did. Charles and Robert's hydrogen balloon flew ten days later.
"It was a four-place biplane with two propeller gasoline engines."
TodayLangley's Aerodrome A was a tandem-wing monoplane with one pilot, Charles Manly. A single 52 hp Manly-Balzer engine drove two propellers. It fell into the Potomac on 7 October and 8 December 1903, the second time nine days before Kitty Hawk.
"6,000 pounds sterling was a fortune."
TodayThe Daily Mail prize for flying the Channel in 1909 was £1,000. The figure may be garbled in the transcript.
The episode follows Maria Skłodowska from her childhood in Russian-ruled Warsaw to her studies at the Sorbonne, her marriage to Pierre Curie and their isolation of radium in a leaky shed. It goes on to her 1903 doctorate, her two Nobel Prizes, her defeat at the Académie des Sciences, her mobile X-ray units in the First World War and her death from radiation-related anaemia. Its themes are perseverance, sharing science freely, and the barriers that women faced in science.
No major errors in this episode. 7 minor slips hidden.
"She's Polish, born in Warsaw, which has just been occupied by the Russians,"
TodayWarsaw had been under Russian rule since 1815, as capital of the Congress Kingdom of Poland. What was new around 1867 was the harsh Russification that followed the crushed January Uprising of 1863–64.
"Mathematics from the University of Paris to, first, Marie Sklodowska."
TodayShe came first in the physics licence (1893) and second in the mathematics licence (1894).
"The University of Paris has never awarded a doctorate to a woman. It's unprecedented, and a foreigner, well."
TodayThe American astronomer Dorothea Klumpke received a doctorate in mathematical sciences from the University of Paris in 1893, ten years before Curie, with a thesis on Saturn's rings. Women had received Paris medical doctorates since Madeleine Brès in 1875. Curie's 1903 thesis made her the first woman in France with a doctorate in physics.
Why it was believedEve Curie's 1937 biography and the many popular lives based on it presented Marie as the first woman at every step, and Klumpke had been largely forgotten.
"At the time, not one other woman had a doctorate in science."
TodayBesides Klumpke in Paris, several women had science doctorates elsewhere by 1903. Sofia Kovalevskaya received a mathematics doctorate from Göttingen in 1874, and a number of women had science PhDs from Swiss and American universities.
Why it was believedThe same "first woman" framing found in popular Curie biographies.
"It's the highest scientific award in all of England."
TodayThe Royal Society's Davy Medal, given jointly to Pierre and Marie in 1903, is a chemistry medal. The Society's highest award is the Copley Medal.
"She spends her vacation in Switzerland where she meets a remarkable young man, Albert Einstein."
TodayThey had already met at the first Solvay Conference in Brussels in 1911, and Einstein wrote her a supportive letter during the Langevin scandal that year. The 1913 trip was a hiking holiday in the Engadin that they took together.
"It was diagnosed for at the time they didn't know that radiation could be deadly."
TodayBy 1934 the danger was well known. Radiologists had been dying of radiation injuries since the 1900s, the British X-ray and Radium Protection Committee issued rules in 1921, and the "Radium Girls" deaths were public by 1925–28. Several of Curie's own co-workers had died. What was missing was a precise idea of the safe dose, and Curie herself long played down the link to her own illness. Her death certificate gave "aplastic pernicious anaemia".
Why it was believedThe "innocent pioneers who could not have known" story was the standard heroic account.
Framed by the Trinity test and Hiroshima, the episode tells Einstein's life: a rebellious schoolboy in Munich, a student in Zurich with Mileva Marić, a patent clerk in Bern who produces light quanta, E=mc² and relativity, then fame, Nazi persecution and exile to Princeton. It explains the twin paradox, light bending near the Sun and the nuclear chain reaction, and stresses that the bomb was a collective effort, not Einstein's invention.
"Look here, Albert. It won't do expelled from school."
TodayEinstein was not expelled. He left the Luitpold Gymnasium in Munich at 15 (1894) on his own initiative, with a doctor's certificate. A teacher had told him his presence undermined class discipline, which is where the legend comes from. The show does avoid the bigger myth that he failed mathematics.
Why it was believed"Expelled genius" stories were standard in popular Einstein biographies.
"Suppose we call them photons."
TodayIn 1905 Einstein spoke of "light quanta" (Lichtquanten). The word "photon" was coined by Gilbert N. Lewis in 1926.
"And we mustn't forget that Milevo was a big help."
TodayAround 1990 the claim that Mileva Marić co-created relativity was widely discussed. It followed the 1987 publication of the couple's love letters and a 1990 AAAS presentation by Troemel-Ploetz and Walker. Historians such as Stachel and Renn already doubted it. Later work, especially Esterson & Cassidy's Einstein's Wife (2019), found no documentary evidence that she contributed to the physics of the 1905 papers. Scenes showing her doing calculations for "our theory" go beyond the evidence.
"Here's the formula. E equals mc squared."
TodayThe show places E=mc² in Einstein's student years with Mileva, before the patent-office job (1902). The mass–energy equivalence paper came in September 1905, written in Bern after the special relativity paper.
"In 1913, Einstein is named director of the Kaiser Wilhelm Institute in Berlin."
TodayIn 1913 he was appointed to the Prussian Academy and a Berlin professorship, and he moved in 1914. The Kaiser Wilhelm Institute for Physics was founded in 1917, with him as director.
"Lever refused to go with him. In any case, their marriage was on the rocks."
TodayMileva did move to Berlin with the children in spring 1914. She went back to Zurich that July after the marriage broke down.
"May I welcome you to Princeton University."
TodayIn 1933 Einstein joined the new Institute for Advanced Study in Princeton, not Princeton University. The Institute was then housed in the university's Fine Hall, so the mix-up is understandable.
"I forgot my address."
TodayThe story that Einstein phoned the Princeton office to ask for his own address circulates without any good source and is best treated as a legend. The homework-help anecdote with the neighbour's girl, by contrast, has some basis.
Why it was believedAbsent-minded-professor anecdotes were attached to Einstein in countless popular books.
"Yes, E is energy and it equals M, the mass of the explosive multiplied by C, the constant speed of light squared."
Todaym is the mass lost in fission, not the mass of the explosive. In the Hiroshima bomb, less than a gram of the roughly 64 kg of uranium was converted to energy. E=mc² also does not explain how a bomb works. The chain reaction does that.
The episode contrasts Descartes' "animal-machine" and Pavlov's reflexes with ethology, the study of animal behaviour in natural conditions, through Konrad Lorenz's life with jackdaws, greylag geese and ducks at Altenberg. It shows imprinting, lifelong pair bonds, learned recognition of predators and ritualised fighting. It ends with Lorenz's thesis that animals have an inhibition against killing their own kind that humans have lost.
"Children, if I were you, I wouldn't be too worried. Dogs almost never kill each other."
TodayLorenz's best-known example, the wolf baring its throat to stop the fight, does not hold in the wild. Mech and others had recorded wolves killing wolves by the 1970s. Later studies found fights between packs to be a leading natural cause of wolf death (Mech et al., Denali, 1998; Cassidy et al., Yellowstone, 2015).
Why it was believedThe same Lorenz bestsellers. His observations came mostly from captive and domestic animals.
"Newton, an apple, fell on his head."
TodayStukeley and Conduitt report that Newton saw an apple fall in a garden, which got him thinking about gravity. The apple hitting him on the head is a later embellishment.
Why it was believedThe head-bonk version was a cartoon and schoolbook staple.
"Faraday liked watching lightning."
TodayFaraday's discoveries (electromagnetic rotation 1821, induction 1831) came from laboratory experiments with wires, magnets and coils, not from watching lightning. The "laws of electromagnetism" as a full theory are Maxwell's. Lightning studies are associated with Franklin.
"For instance, animals of the same species rarely kill each other."
TodayThis is Lorenz's On Aggression (1963) thesis. Field research had already contradicted it by 1994: infanticide in langurs (Hrdy, 1977) and lions (Bertram, Packer), lethal "wars" between chimpanzee groups at Gombe (1974–78), and E. O. Wilson's remark (1975) that murder is far more common in many mammals than in humans. Killing within a species is now known to be widespread in mammals (Gómez et al., Nature, 2016).
Why it was believedOn Aggression and King Solomon's Ring were huge bestsellers, and Lorenz's Nobel (1973) gave his ideas authority with the public.
The episode runs through dreams of reaching the Moon from Lucian's whirlwind and the Persian king's eagles to Tsiolkovsky's rocket theory, Goddard's liquid-fuel rocket and von Braun's V-2. It then stages the Soviet–American space race as a table-tennis match between leaders. Most of the episode reconstructs Apollo 11: Armstrong's Gemini 8 emergency, the boulder-strewn landing site, the computer alarms and the first step.
No major errors in this episode. 4 minor slips hidden.
"Just when our rockets with the 4,000-kilometer range were almost ready."
TodayThe intercontinental A9/A10 "Amerika-Rakete" existed only as studies and design drawings. It was nowhere near ready in 1945. The V-2 (about 320 km range) was Germany's only operational ballistic missile.
"They couldn't get back, not enough fuel to return to orbit."
TodayThe lunar module had a separate ascent stage with its own propellant. Until touchdown the crew could abort at any time by firing it back to orbit, and a landing on uneven ground was not by itself a death sentence. The real risks were running the descent stage dry before landing (about 25 seconds of margin) and a failure of the single ascent engine afterwards.
"We've lost them. They'll die on the moon, and they'll know they're going to die."
TodayMission Control never lost contact with Eagle. Earth talked to the lunar module directly while Columbia was behind the Moon. What was uncertain was Eagle's exact position (it landed about 6 km past the target), and Collins failed to spot it through his sextant. The panic is dramatisation.
"Americans, Russians, Chinese, Indians, Eskimos, people in Africa, Puan, and the French, the Italians."
TodayThe audience of about 500–600 million is a fair estimate, but China did not broadcast the landing, and Soviet television did not show it live, only brief clips later. Russian and Chinese viewers were mostly not watching.
The final episode imagines 2020. There are robot butlers, suborbital airliners, school bags with built-in computers linked to a "memory bank", and a World Assembly that votes on colonising Mars, with the arguments over cost, health, radiation and robots versus humans. A rogue asteroid forces the Mars ship to be diverted. The episode ends on terraforming Mars and future starships (nuclear, laser-sail, fusion, antimatter), arguing that discovery is part of human nature.
"is located between 60 and 100,000 kilometers from Earth,"
TodayMars is about 55–100 million km from Earth at close approaches and up to about 400 million km at the far side of its orbit. "Thousand" is probably a dub or transcription slip for "million". The "200 to 300 times our distance from the moon" that follows fits close approaches only.
"and rising to a height of 27 kilometers, the little Martians would be giants."
TodayOlympus Mons was put at about 25–27 km from Viking-era data. Mars Global Surveyor's laser altimeter (MOLA, 1997–2001) measured about 21.9 km above the Martian datum, or about 26 km above the surrounding plains. "Big as France" is also generous: its roughly 600 km base covers about half the area of France.
"Great quantities of this will be spread over the poles on Mars,"
TodayDarkening the polar caps to release their CO₂ and warm Mars was Carl Sagan's 1973 proposal. Jakosky & Edwards (Nature Astronomy, 2018), using MAVEN, Mars Express and orbiter data, found that Mars no longer has enough accessible CO₂ to thicken its atmosphere usefully with known technology.
"where the sea flowed into a bottomless pit."
TodayEducated 15th-century Europeans knew the Earth was round. The fears around Cape Bojador recorded by Zurara were shoals, violent currents, a "Sea of Darkness", a boiling tropical sea and not being able to sail back, not falling off the edge of the world.
Why it was believedThe flat-earth-explorers myth spread from Washington Irving's 1828 Columbus biography. Jeffrey Burton Russell had debunked it in 1991, but it was still common in children's media.
"you'd see your fellow passengers aging before your merry eyes."
TodayUnder relativity, passengers on the same ship age normally relative to each other. Time dilation shows up only between the ship and people left behind. Tachyons ("300 times faster still") are purely hypothetical, have never been detected, and could not be used for travel without breaking causality.