Secrets of the Prague Astronomical Clock

Like other astronomical clocks, the famous Prague example is effectively a specially designed mechanism to display astronomical information. The next most impressive part is a set of seemingly stationary statues dedicated to four ‘evils’ or ‘vices’ next to the clock and four ‘virtues’ next to the lower calendar dial. Below the main astrolabe and clock is the calendar dial with various painted ‘medallions’, each one representing the calendar months.

Source: interestingengineering.com