Astronomical Clock

This clock is a medieval machine that still works. The first documentary record dates from 9 October 1410: that year the clockmaker Mikuláš of Kadaň built the mechanism and the astronomical dial, probably following the calculations of Jan Šindel, a university professor.

1How to read it

The upper dial is an astrolabe: it shows the position of the Sun and Moon in the sky, the zodiac and several kinds of time at once, including old Bohemian time. The lower one is a calendar of months and signs painted by Josef Mánes in 1865–1866; the original is in the City Museum and what you see is a copy. When the hour strikes, the skeleton pulls its rope, the windows open and the twelve apostles parade past, carved after the fire of 1945. A golden rooster crowns the show.

2Master Hanuš

The legend, popularised by Alois Jirásek in his «Old Czech Legends» (1894), says the clock was made by Master Hanuš and that the councillors had him blinded so he could not build another one elsewhere. In revenge, the master thrust his hand into the mechanism and stopped it for years.

The clock of 1410 is history; the blinded clockmaker is legend.

In reality, Jan Růže, known as Hanuš, maintained and modified the clock in the late 15th century, but he did not invent it. The mistake was cleared up in the 20th century when the copy of the 1410 document was found.

3What to look for

• The skeleton, turning an hourglass and pulling the bell.
• The golden hand that points to the hour on the dial.
• The rooster that appears above the apostles' windows.