The large dial on the front of the clock includes chapter rings for the French hours (I–XII), Italian hours (1–24 beginning at sundown), and Nürnberg hours (divided into daylight and night hours, which vary according to the season of the year), as well as a calendar. The main dial on the back of the clock is an astrolabe, showing the apparent motions of nearly twenty stars in the northern hemisphere; the hands indicate the positions of the sun and moon in the zodiac, the phases and age of the moon in its monthly cycle, and mean solar time. Repoussé scenes on the base personify the Four Seasons.