The later plain silver inner and outer cases, inner case hallmarked for London 1805 and stamped with the maker’s mark D.W, for Daniel Walker of Clerkenwell Close.
The fine original enamel dial has Roman hours inside the division ring with gold ‘arrow’ hour hand and a ‘poker’ minute hand. Signed for Jessop, Southampton Street Strand, London above the centre. The subsidiary Arabic seconds ring set at VI with a fine blued steel counterbalanced seconds hand. The dial reverse,2signed by the enameller Weston, probably William Weston of Smithfield.
The finely engraved gilt full plate movement with turned pillars, punchmarked for Wright’s Patent (only in use in 1783/4), and signed for Jessop, Southampton Street, London. Earnshaw’s spring detent escapement with pierced foliate and mask engraved balance cock, large diamond endstone, gilt-brass three-armed balance, the conforming engraved top plate inset with a silvered regulation dial and gold hand. The gilt-metal dust cover further signed for Jessop, London.
The Time Museum, Rockford, Illinois, USA, inventory no.4127;
Anthony Randall, The Time Museum Catalogue of Marine Chronometers, exhibit no.52
Earnshaw’s spring detent
Thomas Earnshaw for Josias Jessop, London. Circa 1783
An historically interesting and important George III pocket chronometer with Wright’s patent punchmark, retailed by Josias Jessop, in a later silver pair case