A Victorian walnut cased two day marine chronometer by Frodsham & Keen

A Victorian walnut cased two day marine chronometer by Frodsham & Keen, the circular single fusee brass movement with four turned pillars and Harrison's maintaining with an Earnshaw type spring detent escapement and split bi-metallic balance and helical balance spring, with an engine turned backplate, the 4inch silvered dial with Roman numerals, subsidiary seconds and up/down dials, signed 'Frodsham & Keen, 17. South Castle St. Liverpool' and numbered 'No.3390', mounted on a brass gimbal, the twin hinged case with brass mounts and mother of pearl maker's plaque and escutcheons, the lid with a vacant brass plaque, the sides with sunken brass handles, 18.8cm high, 18.3cm wide, 18.2cm deep, together with a book on the Frodhsams, Vaudrey Mercer, The Frodshams, The Story of a Family of Chronometer Makers. (2)