An extremely rare and fine mid-19th century brass-bound rosewood two-day marine chronometer with Hartnup balance. Previously with the Time Museum, and more recently exhibited at The Prescot Museum

William B Crisp, London, Number 381
The three-part case with missing cartouche to the top lid, the centre section with brass flowerhead button above an ivory signature plaque, Hartnup Balance Willm. B. Crisp London No 381, the lower section with campaign hanldes, inlaid brass escutcheon and blank ivory number plaque. Internally, the case has a full-length hinge, gimbal lock and safety winding key secured in a quadrant. The centre section applied with a label for Thomas Petley, Chronometer, Watchmaker and Nautical Optician, Sydney, New South Wales and D,McGregor & Co., Greenock, Scotland. The 3.75-inch silvered dial signed across the centre Willm. Crisp Maker to the Admiralty 81 St.John Street Rd London No 381 with Arabic minute ring framing the Roman chapters, with gold spade hands, the subsidiary power reserve dial at XII running from 0-56hours in 8 one-hour increments with instruction to wind at 24, the large observatory-style seconds dial between V-VII with blued steel hands. The spotted full plate movement with four ringed pillars and maintaining power to the reverse chain fusee, free sprung blued steel helical balance spring with diamond endstone to an Earnshaw type escapement with Hartnup balance, sitting in a weighted, gimballed bowl. Ticking, together with a Tipsy key. 20cms (7.5ins) high