Silver plated barrel-edge case, casemaker JB (probably John Bacon, Clerkenwell). 7-jewel fullplate fusee movement of typical Prest layout, the balance with diamond endstone. Single-roller detached lever escapement. Steel balance, spiral balance-spring. Signed enamel dial, gilt hands. 46 mm diameter.
Thomas Prest, for many years foreman at J R Arnold’s chronometer manufactory in Chigwell, Essex, and patentee of the first successful keyless work for watches – Patent 4501, October 1820. After retiring from Arnold’s, Prest is known to have sold a few interesting clocks and watches, and I believe he started numbering his watches from 500. See also the short note on Prest by Clive Osborne in Antiquarian Horology, March 1963.
Mis-matched hands, the dial with the usual hair cracks, and the plating on the case showing some wear. Otherwise in good original condition. Not serviced by me and winding and ticking OK, but priced accordingly.