This incredible clock, built by Auguste-Lucien Vérité in the late 19th century in Saint John’s Cathedral, is considered a masterpiece of the genre. It has 30,000 moving parts and shows 122 indications that are all interdependent (times, dates, seasons, lengths of day and night, the time of day at 20 locations around the world, number of lunar and solar eclipses, signs of the zodiac, date of Easter (epact: age of the moon on 1 January of each year, indicated by the number of days to be added to the lunar year to make it consistent with the solar year), dates and times of tides, solar time, solstices…
It took two years to build and three years of adjustments and improvements before it was “set into motion”.