Swiss silver thermometer made for the Ottoman market Circa 1810

Silver pocket thermometer with compass      
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An extremely rare Swiss silver pocket thermometer and compass by Houriet made for the Ottoman market, circa 1810. The plain silver case has an engraved compass with Ottoman lettering on the reverse. A very fine white enamel dial on the front with Ottoman numbers and lettering signed by Houriet, steel hands. Comes with the original presentation box.
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Diameter: 64 mm
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Weight: 136 g
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Signed: Houriet Le Locle
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This is the only known thermometer made for the Ottoman market signed by Houriet!