Very rare French nickel plated lever chronograph Circa 1935

Nickel plated inking chronograph
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A very rare French nickel plated open faced keyless inking chronograph, circa 1935. The movement with a lever escapement. A plain case. Black enamel dial with multi scales including a fifth of a second chronograph and metal hands. The dial is signed.
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Diameter: 67 mm
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Weight: 166 g
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Signed: Breitling  Swissaphon Prima
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Inking chronograph
An inking chronograph looks like a pocket watch, but it is not a watch. It is a mechanism to record elapsed time, which is indicated by dots of ink on the dial. The inking chronograph was invented in 1821 by Nicolas-Mathieu Rieussec, who was a watchmaker to King Louis Philippe of France.