58 Fun Facts About Clock

The word 'clock' comes from the medieval Latin clocca, meaning what?

Early tower clocks had no dials at all; they simply rang the hours, so the name for the bell became the name for the machine.

Along with sundials, which device is possibly the oldest time-measuring instrument?

The water clock: the Greeks called it the clepsydra, 'water thief'. Flowing water is hard to keep steady, so it was never very accurate, which pushed clockmakers towards machines.

Which invention made the first mechanical clocks possible in Europe around 1300?

The verge escapement lets a falling weight's pull out one tick at a time; it ruled clockmaking for about 350 years, until the pendulum arrived in the 1650s.

Which English cathedral's iron clock, thought to date from 1386, is said to be the world's oldest still working?

Salisbury: its faceless clock, built only to strike the hours, was pushed aside for a new one in 1884, lay forgotten for over forty years and was restored to working order in 1956.

In which country was a towering astronomical clock built in the 11th century, long before Europe's mechanical clocks?

China: the polymath Su Song built the tower in Kaifeng, where it turned a celestial globe and sounded the hours. Carried off when the capital fell in the 1120s, it was never made to run again.

On a 12-hour clock, what do the letters AM stand for?

Ante meridiem, Latin for 'before noon'. Noon itself is neither before nor after noon, which is why the US time-standards agency calls '12 AM' and '12 PM' ambiguous and best avoided.

Clockmaking flourished in the 15th and 16th centuries in which two German metalworking towns?

Nuremberg and Augsburg led the craft. Nuremberg's Peter Henlein is often credited with inventing the watch, yet spring-driven clocks were already being made before he was born.

Who is usually credited with inventing the pendulum clock in 1656?

Christiaan Huygens's pendulum cut a clock's daily error from about a quarter of an hour to under a minute.

French scientists considered defining which unit by a pendulum that swings once a second?

Metre: such a pendulum is about 99.4 cm long. France chose the Earth's meridian instead, and surveying it from Dunkirk to Barcelona took two astronomers over six years.

Salvador Dalí painted melting watches draped over a branch and a ledge in which 1931 work?

The Persistence of Memory's soft watches were inspired, Dalí said, by Camembert cheese melting in the sun, not by Einstein's theory of relativity.

The 1675 invention of the spiral balance spring, or hairspring, finally made what possible?

Accurate pocket watches arrived because the hairspring made the balance wheel swing at a steady rate, and watchmakers soon began adding a minute hand.

How much did the British government offer in 1714 for a way to determine longitude accurately?

£20,000 was the top prize, for longitude within half a degree. John Harrison chased it for decades and won his last payment in 1773 only after appealing to King George III.

What was John Harrison's original trade before he turned to clockmaking?

Carpenter by trade and self-taught in clockmaking, Harrison built his early clocks almost entirely of wood, and even his first sea clock ran on wooden wheels.

How far out was Harrison's H4 watch when it reached Jamaica on its 1761–62 sea trial?

About 5 seconds slow, an error of roughly one nautical mile. The Board of Longitude still was not convinced and demanded a second trial, to Barbados.

Harrison's nearly frictionless, oil-free escapement is named after which creature?

Grasshopper is also the shape of a modern tribute: on Cambridge's Corpus Clock a giant metal insect, the Chronophage or 'time eater', works as the escapement.

Whose 1995 bestseller Longitude brought Harrison's story to a wide audience?

Dava Sobel's book became a 2000 TV drama, with Michael Gambon as Harrison and Jeremy Irons as the retired naval officer who restored his sea clocks in the twentieth century.

What did clockmaker Alexander Bain pioneer in 1843, using pendulums to send images by wire?

The fax machine began with Bain's 1843 patent, in which a clock kept two pendulums in step to scan a message line by line. A practical version took other inventors until the 1860s.

The first quartz clock was built in 1927 at which company?

Warren Marrison and J.W. Horton built it, exploiting the piezoelectric effect the Curies had found in 1880.

Which company produced the world's first quartz wristwatch, the Astron, in 1969?

Seiko's Astron set off the quartz crisis: cheap, accurate quartz watches hit Swiss mechanical makers so hard that the plastic Swatch was launched in 1983 to win buyers back.

The first accurate atomic clock, built in 1955, kept time by the vibrations of which element's atoms?

Caesium in these clocks is the stable form, not the radioactive one. Louis Essen's clock counted its atoms' microwave rhythm, which proved so steady that in 1967 it replaced astronomy as the basis of the second.

Which everyday technology relies on atomic clocks in orbit that are set to tick slightly slow to offset relativity?

Satellite navigation depends on it: clocks on GPS satellites gain about 38 millionths of a second a day from relativity, enough to throw positions off by about 10 km a day if left uncorrected.

Strictly speaking, what does the name 'Big Ben' refer to?

The Great Bell got the nickname first, perhaps after Sir Benjamin Hall, who oversaw its installation, or after the boxer Ben Caunt. Only later did 'Big Ben' spread to the clock and its tower.

In 2012, Big Ben's clock tower was officially renamed what?

Elizabeth Tower marked Queen Elizabeth II's Diamond Jubilee and matched the palace's Victoria Tower, once the King's Tower, renamed for the only other monarch to reign sixty years.

Big Ben's tower rose after what destroyed the old Parliament in 1834?

Fire broke out in October 1834 when furnaces burning the Exchequer's old wooden tally sticks overheated. The clock tower of the new palace was finished in 1859.

Which observatory's red time ball has dropped at 1 pm daily since 1833 so ships' navigators could set their clocks?

Greenwich's ball let ships in the Thames check their chronometers at a glance. The idea spread to ports worldwide and lives on in New York's New Year's Eve ball drop in Times Square.

How is Big Ben's clock traditionally kept to time?

Pennies placed on the pendulum raise its centre of mass, which makes it swing faster: each old penny added makes the clock gain about two-fifths of a second a day.

In the 1923 comedy Safety Last!, which silent-film star dangles from the hands of a skyscraper clock?

Harold Lloyd hung from that clock with a right hand missing its thumb and forefinger, blown off in 1919 by a bomb he took for a prop and hidden on screen by a special glove.

Big Ben's quarter-hour chimes are known by what name?

The tune came from Cambridge and is said to be based on a phrase from Handel's Messiah.

Which region of Germany popularised the cuckoo clock and exported it worldwide?

The Black Forest made the cuckoo clock famous but did not invent it: the first known description dates from 1629, before clockmaking had taken hold in the region.

Which actor, as Harry Lime in The Third Man, quips that centuries of Swiss peace produced only the cuckoo clock?

Orson Welles wrote the speech into the script himself, by Graham Greene's account. He later recalled that the Swiss 'very nicely pointed out' they had never made any cuckoo clocks.

What produces the cuckoo call inside a traditional mechanical cuckoo clock?

Two small pipes with bellows make the call: the movement lifts each bellows in turn and lets it drop, sounding the higher note first and then the lower.

Friedrich Eisenlohr, architect of Baden's first train stations, modelled his classic 1850 cuckoo clock case on what?

A railway house: Eisenlohr put a clock dial on the front of a railway guard's house he had designed, and his 'Bahnhäusle' went on to push other cuckoo clock shapes off the market.

In which Dickens novel does Miss Havisham keep every clock stopped at twenty minutes to nine?

Great Expectations gives the reason: twenty to nine was the moment a letter told her she had been jilted on her wedding day, and she has worn the dress ever since.

Coordinated Universal Time, the standard the world's clocks are set by, goes by which three-letter abbreviation?

UTC matches neither language: English would give CUT and French TUC, so to avoid favouring either, one neutral abbreviation was chosen for every country.

What is the hourly animated show on Prague's astronomical clock called?

The Walk of the Apostles brings the twelve past two small windows while a skeleton, Death, rings his bell and the figures beside him shake their heads, not ready to go.

By legend, what did Prague's councillors do to clockmaker Hanuš so he couldn't build another?

Blinded him, the legend says, so he wrecked the mechanism in revenge. In fact the clock was made in 1410 by Mikuláš of Kadaň, and Hanuš was wrongly credited with it for centuries.

The song that named the grandfather clock ends with it doing what?

Stopping dead: in Henry Clay Work's 1876 hit 'My Grandfather's Clock' the clock halts for good the moment the old man dies. Furniture dealers soon borrowed the title as a name for the clocks.

Which American's 1784 joke about Parisians rising at sunrise is often called the origin of daylight saving time?

Benjamin Franklin's satire proposed taxing window shutters and firing cannons at sunrise, yet he never suggested changing the clocks.

By what name do clockmakers know grandfather clocks, nicknamed after an 1876 song?

Longcase clocks, or tall-case clocks, need the height: the case houses a long pendulum and the weights that sink slowly as the clock runs.

Which organisation maintains the Doomsday Clock?

The Bulletin of the Atomic Scientists was founded in 1945 by Manhattan Project veterans. For its 1947 cover, artist Martyl Langsdorf first thought of using the symbol for uranium before settling on a clock.

At what time was the Doomsday Clock first set in 1947?

Seven minutes to midnight was an artist's call, not a calculation: Martyl Langsdorf said she set the hands there partly because it looked good to her eye.

The Doomsday Clock's furthest-ever setting from midnight marked the end of which conflict?

The Cold War's end pushed the hands back to 17 minutes in 1991, after the United States and the Soviet Union signed their first treaty to cut, not just cap, long-range nuclear weapons.

Levi Hutchins's 1787 American alarm clock had what limitation?

It only rang at 4 am because Hutchins built it solely for himself, adding a single extra gear that struck a bell at the hour he wanted to get up for work.

In Groundhog Day, which song does Bill Murray's clock radio play every morning?

I Got You Babe, the Sonny & Cher hit, greets Phil each time the day resets. The Punxsutawney he can't escape was really Woodstock, Illinois, where almost all of the film was shot.

How many minutes was the snooze on the first snooze-button alarm clock, 1956's 'Snooz-Alarm'?

Nine minutes is said to have been a gear compromise: the snooze had to fit existing clockwork, which allowed a little over nine minutes or a little over ten, and ten was judged too long.

Which Athenian philosopher is said to have rigged up an alarm clock to wake his students for dawn lectures?

Plato's alarm survives only in later reports that disagree on the details: one has it sounding like an organ, another dropping lead balls noisily onto a copper platter.

Clock hands turn 'clockwise' because that is the direction of what?

A sundial's shadow in the northern hemisphere sweeps round the dial in that direction, and the first clockmakers copied it. South of the equator the shadow turns the other way.

In Peter Pan, why is Captain Hook glad that the crocodile hunting him once swallowed a clock?

He hears it coming and bolts. The crocodile got its taste for Hook when Peter fed it his hand, and Smee warns him that one day the clock will run down.

Which country reversed the clock on its Legislative Assembly in 2014 to promote indigenous values?

Bolivia's foreign minister dubbed it the 'clock of the south', asked 'Who says that the clock always has to turn one way?' and gave left-turning clocks to delegations at a summit.

Which English king's astronomical clock at Hampton Court Palace still shows the time of high tide at London Bridge?

Henry VIII's court reached Hampton Court by barge, so the 1540 clock showed when the tide made London Bridge, a dangerous run of rapids at low tide, safe to pass.

What does every modern clock, whether pendulum, quartz or atomic, rely on to keep time?

A harmonic oscillator is anything that swings or vibrates at a steady rate, and the clock simply counts the swings. A typical quartz crystal vibrates 32,768 times a second, just above the range of human hearing.

Which island gives its name to an ancient Greek clockwork device, the oldest known analogue computer, found by divers in 1901?

Antikythera is where sponge divers found the corroded bronze in a Roman-era wreck. Its gears predicted eclipses and tracked the cycle of the Olympic Games, and nothing as complex is known again until the 14th century.

Which university city, where Galileo later taught, was home to the Astrarium, a 14th-century clock with seven faces and 107 gears?

Padua's Giovanni Dondi spent sixteen years on it. The original is lost, but he described every part so fully that modern clockmakers have built working reconstructions from his manuscript.

Eli Terry made clocks cheap enough for ordinary homes by pioneering which manufacturing method?

Interchangeable parts let Terry take on an order for 4,000 wooden clock movements, cutting identical wheels by machine instead of shaping each one by hand.

In Chinese culture, giving someone a clock is taboo because the phrase sounds like what?

Attending a funeral, 'sòngzhōng', sounds just like 'sòng zhōng', giving a clock. A giver who slips up can ask for a small coin in return, which turns the unlucky gift into a purchase.

The Ayrton Light atop Big Ben's clock tower is lit to signal what?

The Commons sitting after dark, or either House by some accounts, lights the lantern. It was added in Queen Victoria's reign so that she could see from Buckingham Palace whether members were still at work.

As of 2025, which city's Abraj Al-Bait tower carries the world's largest clock faces?

Mecca's clock tower stands where an 18th-century Ottoman fortress was demolished in 2002 to make room for it, a move that drew protests from Turkey.

Which German city's town-hall Glockenspiel re-enacts a 1568 ducal wedding with life-size figures and a joust?

Munich's Glockenspiel, added to the New Town Hall in 1908, replays the wedding of Duke Wilhelm V, and the knight in Bavaria's white and blue wins the joust every time.