French 18K gold cylinder watch with 15-day power reserve Circa 1850

Gold open faced cylinder watch by Gontard
–
A rare French 18 carat gold open faced cylinder pocket watch with a 15-day power reserve, circa 1850. Brass movement, large barrel (38 mm) with power reserve indicator, cylinder escapement, three-arm brass balance. White enamel dial with Roman hours, outer minute divisions and sunk subsidiary seconds at 6 o’clock. Plain bezels, reeded band, the case back engine-turned. Dial signed, case numbered, movement signed and numbered, case and movement with matching numbers.
–
Diameter: 47 mm
–
Weight: 87 g
–
Signed: Gontard et Cie à Paris
–
Gontard, Paris, made these watches with a 15-day power reserve and different escapements. His power reserve indication required the cover on the movement to be closed so that the balance was fitted under the dial.