Archivo: Clepsydra-Diagram-Fancy

Description: Diagram of a fancy clepsydra, this type being an automaton or self-adjusting machine. Water enters and raises the figure, which points at the current hour for the day. Spillover water operates a series of gears that rotates a cylinder so that hour lengths are appropriate for today's date. The ancient Greeks and Romans had twelve hours from sunrise to sunset; since summer days are longer than winter days, summer hours were longer than winter hours.
Title: Clepsydra-Diagram-Fancy
Credit: Abraham Rees (1819) "Clepsydra" in Cyclopædia: or, a New Universal Dictionary of Arts and Sciences The image is the JPEG reproduction published 2007-02-01 by the Horological Foundation.
Author: The illustrator was probably w:John Farey, Jr. (1791–1851). The principal engraver for the encyclopedia was Wilson Lowry (1762–1824).[1]
Usage Terms: Public domain
License: Public domain
Attribution Required?: No