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Prague Built a Clock That Refuses to Choose What Time Means

Czechia has finished first in the world for beer consumption per person every single year since 1993. The country was founded in 1993.

The figure moves around depending on the year and who is counting — recent estimates run somewhere between roughly 128 and 150 litres per person per year, which works out at something like 250 to 300 half-litre glasses annually for every man, woman and child in the country. It has been falling for two decades and Czechia is still comfortably first. Only Austria and Germany have ever come close, and neither has passed it.

Prague also has a reasonable claim to have caused the situation. Pilsner — the pale golden lager that now accounts for the overwhelming majority of beer drunk worldwide — was invented in 1842 in Plzeň, about eighty kilometres away.

So the city has spent six hundred years operating a clock that shows four different kinds of time, in a country that has been first in one specific global ranking for every year of its existence.

The Orloj has been running on the south wall of Prague's Old Town Hall since 1410, built by the clockmaker Mikuláš of Kadaň with the astronomer Jan Šindel. It is the oldest astronomical clock in the world still in operation, and most of the iron inside it is original.

Every hour, two hatches open. Twelve Apostles process past in pairs. Figures of Death, Vanity and Greed move alongside them. A golden rooster crows, a bell tolls, and the whole thing is over in about forty-five seconds. Crowds have been gathering in the square for it for six hundred years.

But the show is not the remarkable part. The dials are.

The clock: the Orloj displays, simultaneously, four completely different systems for measuring the day.

Old Bohemian time, in which the day begins at sunset. This is the same principle Ottoman Istanbul ran on — gurubi time — and abandoned by law in 1926.

Babylonian time, in which the day begins at sunrise and the daylight hours are divided into twelve regardless of how long the day actually is, so an hour in June is longer than an hour in December. This is the same principle behind Swahili time in Nairobi and the Ethiopian clock in Addis Ababa.

Central European time, marked by a hand shaped like a sun. The modern system: fixed hours, counted from midnight.

Sidereal time, measured against the stars rather than the sun, and very slightly shorter than a solar day.

Plus the position of the sun and moon in the zodiac, the phase of the moon, and a calendar dial marking the day of the year and the saints' feast days that once set the timing of medieval fairs.

One clock face, four answers to the question of when a day starts, all of them running at once, all of them correct.

Elsewhere in this series, cities argued about these systems and picked one. Istanbul chose midnight and passed a law. Nairobi kept the sunrise. Prague simply built a machine that shows all of them and let the viewer decide.

It very nearly did not survive. In May 1945, during the Prague Uprising, the Old Town Hall was shelled and the clock burned; many figures and the calendar dial were destroyed. It stood silent for three years until Vojtěch Sucharda rebuilt the mechanism and carved new Apostles.

Prague sits at 14.4° east, on Central European Time, which is built for the 15th meridian. The city's clock is within a couple of minutes of its own sun — one of the most accurately positioned places on this entire site.

The city that built a monument to the idea that time is a matter of interpretation happens to keep, on the wall right next to it, almost perfect time.

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