A skeletonised verge pocket watch movement, William Cooper, Derby, No.580, circa 1770, in associated silver pair cases, later white enamel dial with Roman numerals and eccentric winding hole, signed and numbered gilt fusee movement with chased and engraved skeletonised top plate, plain three armed flat rim steel balance, associated plain pair cases, diameter 49mm.

細節
A skeletonised verge pocket watch movement, William Cooper, Derby, No.580, circa 1770, in associated silver pair cases, later white enamel dial with Roman numerals and eccentric winding hole, signed and numbered gilt fusee movement with chased and engraved skeletonised top plate, plain three armed flat rim steel balance, associated plain pair cases, diameter 49mm.