J. R. Arnold, London. An 18K gold key wind open face chronometer pocket watch Date: Late 18th century and later Movement: Gilt full plate Arnold spring detent, cut and compensated bi-metallic over sized Z balance, helical balance spring, diamond end stone, No.1679 Dial: White, black Roman numerals, black outer minute track, subsidiary seconds at 6, gilt spade hands, No.1679 Case: Later polished hinged round hallmarked for 1874, No.1679 Signed: Dial & movement, case stamped JY Size: 49mm