Swiss silver duplex made for the Chinese market Circa 1880

Silver watch with center seconds
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A Swiss silver key winding pocket watch made for the Chinese market, circa 1880. An open faced pocket watch with deadbeat centre seconds. Contemporary case with an engine turned case back and a fluted case band. White enamel dial with radial Roman numerals and blued steel skeleton hands. Gilded brass movement, engraved Chinese style, going barrel, duplex Jacot escapement, polished steel monometallic balance with blued steel wings balance and blued steel flat hairspring, polished steel index regulator.
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Diameter: 50 mm
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Weight: 87 g
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Signed: No Name
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Duplex Jacot Escapement:
During the last quarter of the 18th century, several watchmakers tried to produce watches with dead center seconds hands, much in favour among the scientific community. The first attempt, made in Geneva by Jean-Moïse Pouzait (1743-1793), circa 1786, featured a lever escapement associated with a large seconds beating balance; the model of this escapement was presented to the local Société des Arts.
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Due to its spectacular aspect, and despite its inertia sensitivity, Pouzait’s escapement was much appreciated by the Chinese before the invention by Charles-Edouard Jacot (1817-1897), a watchmaker from La Chaux-de-Fonds (Neuchâtel mountains), circa 1840-1850, of the so called duplex Jacot or Chinese duplex escapement, with double tooth arrangement. The Jacot escapement, like any duplex escapement, is a frictional one; the friction from the escape wheel is constantly present. Enabled inexpensive production of dead center second watches it was often used in the watches made for the Chinese market.