The astronomical clock of Chiaravalle tower
Gearing scheme of a clock showing moon, sun, hours and minutes
The sheet lays out the gearing scheme of a tower clock, with meshing wheels, dials divided into twelves, and clusters of numbers marking the counts and ratios of the train. A note identifies it as the clock of the tower of Chiaravalle, which displays moon, sun, hours and minutes, and a slender tower is sketched below. The dials for the moon and sun carry figures such as 146, 60, 83 and 3.
On this page
Gearing scheme of the Chiaravalle clock
The diagram sets out the wheel counts of the movement: dials marked 12 for the minutes and hours, 12 24 12 for the hour work, and further wheels bearing 146, 60, 83 and 3 for the astronomical displays. The note names it the clock of the tower of Chiaravalle.
Dials for moon and sun
Beyond hours and minutes the clock is described as showing the moon and the sun, with a wheel labelled 'luna' (moon) and its counts. It is thus an astronomical clock tracking the two luminaries.
The clock tower
A tall, spired tower is drawn at the lower part of the sheet, representing the campanile of Chiaravalle that would carry the movement.