Swiss gold open faced lever chronograph watch Circa 1912

Gold chronograph by Ulysse Nardin
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A Swiss 18 carat gold open faced keyless lever chronograph watch, circa 1912. Nickel finished jewelled lever movement, bimetallic compensation balance. Inscribed gold cuvette. White enamel dial with Breguet numerals, outer calibrated fifths seconds ring with Arabic five minute divisions, two sunken subsidiary dials for 30 minute register and constant seconds. Engine turned case, chronograph operated through the crown, hinged back. Case, cuvette, dial and movement signed, case, cuvette and movement numbered.
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Diameter: 50 mm
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Signed: Ulysse Nardin Locle