French virgule with date and stoppable center seconds Circa 1790

Silver open faced pocket watch by Henry
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A big and technical interesting French deck watch with stoppable center seconds, date and unusual version of virgule escapement, circa 1790.
Very beautiful engine turned silver case with gold hinge and peripheral bolt for stopping the center seconds. Gilt full plate movement, signed and numbered, with very big barrel and an unusual version of virgule escapement (no fusee). White enamel dial with decentralized time indication, center seconds, date with hand and restored seconds hand.
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Diameter: 59 mm
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Weight: 116 g
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Signed: Henry a Paris