Swiss siderial time adjusted observatory chronometer Circa 1954

Silver open faced pocket watch by Ulysse Nardin
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A rare siderial time adjusted Swiss observatory chronometer with contact device for electrical seconds registration with mahogany transport box, static box and Bulletin de Marche by Ulysse Nardin, Le Locle, May 1954. The watch has a silver polished case with a screw back that protects movement. The enamel dial is signed and features radial Roman numerals. Two subsidiary dials are on the watch face: one for the seconds and one for the power reserve indicator. The watch hands are blued spade-shaped. The frosted gilt bridge movement of the watch has a gold screw compensation balance and a cam-type fine-adjusting device.
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Diameter: 64 mm
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Weight: 233 g
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Signed: Ulysse Nardin Locle Suisse Chronometre