English silver open faced important chronometer Circa 1837

Silver unusual pocket watch with chronometer escapement
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An important pocket chronometer, invented and made by Thomas Earnshaw in London, England, circa 1837. This watch has a solid silver case and London Hallmarks for 1837. Its white enamel dial features Roman hour numerals, an outer minute track, a subsidiary seconds dial at 6 o’clock and gold hands. The numbered movement is fitted with an Earnshaw spring detent chronometer escapement, a helical hairspring, diamond end stone, a chronometer balance with trapeze weights and is marked Thomas Earnshaw invenit et Fecit.
The dial and movement have matching numbers and are signed.
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Diameter: 56 mm
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Weight: 161 g
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Signed: Tho^S Earnshaw Inv^T et Fecit
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The timepiece presented here is of historical importance. Today, only a few pocket chronometers signed by Earnshaw are still on the market, most pieces are in important collections and museums, like an example from 1837 in a silver case in the collection of the Time Museum in Rockford, Illinois, U.S.A.