English interesting silver cylinder pocket watch Circa 1787

Open faced collector’s watch by John Crowdhill
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An interesting and very fine quality, early English cylinder watch, with hallmarks London 1787.
Silver case with hallmarks London 1787 and casemaker’s punch WQ;  special feature: middle part of the back made as a rotatable disc, at the same time closing mechanism for the winding stem (extremely rare!), small peripheral opening button, as it is known from very high quality French watches. Dome signed and numbered. Exquisite English movement with cylinder escapement and very big diamond endstone, main plate also signed and numbered. White enamel dial with Roman hours, Arabic minutes and high-grade gold hands.
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Diameter: 48 mm
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Weight: 101 g
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Signed: John Crowdhill London