Fine Swiss silver open faced lever pocket watch Circa 1910

Silver pocket watch by Isaac Grasset & Cie
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A Swiss silver pocket watch, circa 1910. An engine-turned case with polished borders back covers with a vacant cartouche. Glazed silver-rimmed cuvette for viewing the movement. White enamel dial with Arabic numerals, outer minute divisions and Arabic five-minute numerals, subsidiary seconds and gold Louis hands. A matte gilt brass movement, 15 jewels, the mainspring rolled around the winding shaft, straight-line lever escapement, cut bimetallic compensation balance, blued steel Breguet balance spring, index regulator. Movement punched with Swiss Patent numbers 5019 & 14528. Case with Swiss and German hallmarks.
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Diameter: 51 mm
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Signed: Isaac Grasset & Cie  Genève
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Isaac Grasset & Cie A watchmaker who was also a lapidary. His workshop was at 44, rue Wendt. He applied for several patents, such as a polishing and lapidary machine in 1892, a device to set time by means of the pendant in 1896, a micrometric index in 1899, patents No. 5019 and later No. 14528 for a helical mainspring rolled around the winding stem. This device makes the mainspring barrel and the corresponding bridge unnecessary and therefore reduces the cost of these watches. Unfortunately, the such economy was a detriment to their reliability. A new attempt was made, with the assistance of Auguste Meylan, to improve his invention by another patent applied for on September 9, 1892. This latter invention was presented in 1896 at the Geneva Exhibition.