John Roger Arnold

(*) An extremely rare pocket chronometer with spring detent escapement and Z balance according to John Arnold in its mahogany deck watch box with sliding lid Movm. No. 1977, Case No. 1977, Dimensions 54 mm, circa 1804, Weight 135 g, Origin England, Original box Case: Silver, case maker's punch mark "TH" (Thomas Hardy). Dial: Enamel. Movm.: Full plate movement, chain/fusee, spring detent escapement according to John Arnold, Z-balance with 2 weights and 2 screws, freesprung blued helical balance spring with both sides passing terminal curves, very fine florally engraved balance cock, chatoned diamond endstone on balance. This is an extremely rare example of an Arnold pocket chronometer in exceptional and completely original condition. John Roger Arnold (1769-1843) was born in 1769 as the son of the famous watchmaker John Arnold. The craft of watchmaking he began in 1783, first apprenticing with his father and from 1792 on with Abraham-Louis Breguet. He was admitted to the Freedom of the Clockmakers Company in 1796 and became a Master in 1817. After the death of his father, John Roger continued the company on his own until 1830. In this year he moved to Strand 48 and started a 10-year partnership with E.J. Dent; business went well during this time and the partners had the possiblitiy to research and experiment, in particular they investigated the influence of magnetism on chronometers. When the partnership ended in 1840, Arnold continued his work until his death in February 1843. Case: very good. Dial: very good. Movm.: very good, capable of running.