French silver decimal pocket tachometer watch Circa 1860

Silver hunting cased cylinder watch by Paul Garnier
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A fine, rare and unusual French, silver hunting cased decimal pocket tachometer watch, circa 1860.
Calibrated to measure 100 seconds at one-second intervals, central progressive one second register hand and table for calculating the speed in kilometres per hour from the seconds elapsed. With original box and key; produced for the Madrid Zaragoza & Alicante railway company MZA (Compañía de los Ferrocarriles de Madrid a Zaragoza y Alicante), which was at the time the 10th large enterprise in Europe and the 2nd largest in Spain.
A silver, tiered, polished case, engraved monogram MZA, the tachometer table engraved inside the cover calculated for one kilometre. Hinged silver cuvette. White enamel dial with radial Arabic numerals and 10 x 10-second divisions. Blued steel hands. A  frosted gilt brass movement, half-plate with going barrel, cylinder escapement, plain brass three-arm balance, blued flat steel balance spring with a regulator. Tachometer bolt and reset slide in the band. Dial and cuvette signed.
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Diameter: 59 mm
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Weight: 163 g
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Signed: Paul Garnier, Paris