Mechanism of a Timekeeper Horology [study of the measurement of time. Clocks, watches, clockwork, sundials, hourglasses, clepsydras, timers, time recorders, marine chronometers]. Copperplate engraving By J. Pafs From the Encyclopaedia Londinensis or,
Case study about the Chronometer - the Zenith Calibre 135 - Monochrome Watches