Swiss chronometer with Three Bridge Tourbillon Circa 1917

Silver hunting cased pocket watch by Auguste Tschanz
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An outstanding graduate’s work with chronometer escapement and Three Bridge Tourbillon, circa 1917. Accompanied with Bulletin 1ère Classe de l’Observatoire Astronomique de Neuchatel from juni 14, 1949.
Silver, polished, à goutte case with glazed movement, gold crown, and bow and hinge. Enamel dial with radial Roman hours, auxiliary seconds, and blued spade hands. German silver three bridge movement with mirror-polished and bevelled steel bridges, finest mirror-polished screwed gold chatons, bevelled tourbillon steel cage, spring detent escapement, large Guillaume gold screw compensation balance, blued flat balance spring with two terminal curves by Phillips, fine adjusting device with gear and gear segment, and gold escape wheel.
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Diameter: 57 mm
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Weight: 151 g
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Signed: Auguste Tschanz, Ecole d’Horlogerie de Saint Imier
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Auguste Tschanz (1876-1967)
Tschanz worked for Longines and was responsible for the design and production of complicated watches. In 1913 he became a professor at the watchmaking school in Saint-Imier and taught there until 1940.