The A to Z of clocks
One clock for every letter: how they work, who built them, and the stories behind the world's most remarkable timekeepers.
AAstronomical Clock: How Prague's Orloj Maps the SkyPrague's Orloj has shown the Sun, Moon and zodiac over Old Town Square since 1410. Here is how to read it, and…BBig Ben and the Great Clock of WestminsterStrictly speaking, Big Ben is a bell of about 13.7 tonnes. The clock below it and the tower around it have sto…CCandle Clock: Telling Time with Fire and WaxBefore clocks ticked, some people simply watched a marked candle burn down. Done carefully, it worked better t…DSalvador Dalí's Melting Clocks and The Persistence of MemoryA canvas only about 9 by 13 inches gave the world its favorite picture of time going strange: soft pocket watc…EEscapement: The Part That Makes a Clock TickEvery tick you hear from a mechanical clock is the escapement at work, letting the gears slip forward one toot…FFloral Clock: Telling Time with FlowersOne flower clock tells time by which blooms are open. The other is a working clock planted with thousands of f…GThe Grand Central Terminal Information Booth ClockNew Yorkers have been meeting under it for more than a century. Its faces are not opal, and they are probably …HJohn Harrison and the Marine ChronometerA carpenter from northern England spent most of his life building clocks that could keep time on a rolling shi…IIncense Clock: How China Measured Time with SmokeIn China, a smoldering line of incense could mark the night watches, wake a sleeper, or even let you smell wha…JJens Olsen's World ClockA Danish locksmith spent decades calculating a clock he never saw finished. It started ticking in Copenhagen C…KHow to Wind a Mechanical ClockWinding a clock takes a minute a week, but doing it carelessly can be expensive. Here is what conservators and…LThe English Lantern ClockBrass, weight-driven and topped with a bell, the lantern clock was the first clock many English households eve…MThe Moon-Phase DialA painted moon gliding across a small window is one of the oldest complications in clockmaking, and a neat les…NThe Nixie Tube ClockOrange numbers floating in glass: the Nixie tube was built for 1950s lab equipment and found a second life in …OThe Oldest Mechanical Clocks in the WorldSeveral medieval iron clocks claim to be the oldest still working. The evidence is fascinating, and none of th…PThe Pendulum ClockA swinging weight turned clocks from rough guides into precision instruments. Here is how Galileo's idea becam…QThe Quartz ClockA sliver of quartz vibrating thousands of times a second runs most of the world's clocks. Here is how it works…RRailroad Time and the Birth of Time ZonesEvery town once kept its own time. Railways made that impossible, and in fixing it they gave the world standar…SSundials: Telling Time by ShadowThe oldest way to read the time is still one of the cleverest, and it explains why the sun itself is a slightl…TTower and Turret ClocksLong before most people owned a timepiece, a clock high in a church or town tower told a whole community when …UUnusual Clocks Around the WorldSome clocks are built to keep perfect time. These six were built to surprise, to show off, or to make you thin…VThe Vienna Regulator ClockTall, glass-sided and quietly precise, the Vienna regulator turned a scientific timekeeper into one of the mos…WWater Clocks and the ClepsydraBefore gears and springs, people measured time by letting water drip, and the best of these clocks were astoni…XWhy Clocks Show 12 HoursThe numbers on an ordinary clock face are a 3,500-year-old inheritance from Egyptian astronomers, Babylonian m…YThe Clock of the Long NowInside a mountain in West Texas, a mechanical clock is being built to keep time for the next ten thousand year…ZThe Zytglogge, Bern's Clock TowerFor almost 500 years, a hand-wound clock in the heart of Bern's Old Town has been putting on a show of bears, …
Types of clocks
Browse 24 clock types, from banjo to time clocks →
Clock makers and brands
Browse 31 clock makers, from Ansonia to Westclox →
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