Swiss silver lever deck watch with power reserve Circa 1915

Silver open faced deck watch by Paul Ditisheim
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A rare Swiss silver open faced keyless lever deck watch with power reserve and Guillaume balance, circa 1915. The Highest Records at Kew Teddington and Swiss Observatories Mechanical keyless lever movement, 21 jewels, Guillaume balance. Silver cuvette. Silvered matte dial with Roman numerals, blued steel spade hands, subsidiary seconds, outer railway minute divisions and 52 hours power reserve indicator. Large water resistant type case, screw bezel and screw back centred by engraved inscription Paul Ditisheim 703400 Compensateur Guillaume, ribbed band, large ball shaped crown. Case, dial and movement signed and numbered, cuvette numbered and stamped.
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Diameter: 65 mm
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Signed: Paul Ditisheim La Chaux-de-Fonds Switzerland Grand Prix Paris 1900