Breguet Marine Chronographe

A watch that both measures and displays elapsed times and shows conventional time. The chronograph mechanism, driven by the movement of the watch, controls a centre seconds hand that can be started and stopped to time an event. A subsidiary dial records the elapsed minutes. Two pushpieces in the caseband serve to operate and return the chronograph to zero.

With his "chronomètre à doubles secondes, dit d'observation", developed in 1820, which permitted the measurement of intermediate periods or of the length of time taken by two separate and simultaneous events, Breguet anticipated the modern chronograph.