JOHN ROGER ARNOLD No.593: An early Victorian eight-day marine chronometer, circa 1810, the white enamel dial (hair cracks) signed Arnold, London 593 with Roman chapters, gold hour and minute hands, subsidiary 0-8 up-and-down and seconds dials both with blued hands, crescent-shaped main frame signed on the top-plate Jn. R. Arnold, London, 593 with vertical steady ???? and carrying reversed fusee and barrel, sub-frame assembly with Arnold escapement and his spring detent (repaired) carrying centre wheel top pivot and the remainder of the train, Arnold 'Z' balance, cut bi-metallic rim blued on the inside, oversprung blued steel helical balance spring with high section coils of typical Arnold format, very long balance staff and high balance cock, the latter with cam adjuster to top stud, inner brass drum inscribed in ink April 1831 having gilt bezel with bayonet fitting, positioning key ways ? at III and IX, the drum mounted as a completely seperate unit within an outer barss bowl with square-section gimbal, plain two-tier velvet-lined mahogany box with sliding top revealing circular inspection port, revolving brass calendar dial to front of the top section adjusted from within the box, the bottom section fitted with brass-sprung gimbal locking arms engaging with the top of the gimbal ring, external brass chap? handles Dial diameter: 93mm. box: 220mm. sq.