The watch has an unusual and rarely seen dead seconds jumping mechanism. Usually dead seconds are based on a special escapement, double-train movement, or a special mechanism invented by Breguet and employed mostly by him and later by Lange. In this watch the mechanism is completely different; the seconds hand sits on a 60-tooth wheel mounted loosely over the canon pinion and held in place by a small spring-loaded friction roller mounted on a long delicate spring. The wheel is driven by a six-leaf wheel set on the escape wheel pinion. It is one of the simplest dead seconds mechanisms we have seen and apparently quite reliable. Chevalier & Cochet (also Chevallier) Watch- and clockmakers from the late 18th and early 19th century. Made very fine watches for the French and Spanish markets. Specialized in repeating watches and automaton watches with gold cases, decorated with enamel, pearls and precious and semi-precious stones ?Dictionnaire des Horlogers Genevois? by Osvaldo Patrizzi, Antiquorum Editions, Geneva, 1998.