Dent London, Chronometer Maker To the QUEEN, No.2459, with Airy's supplementary compensation The three part case (possibly later) with solid lid over a signature plaque with Ordnance mark, hinged side handles and a circular lock, the signed and numbered 3.75 inch silvered dial with outer minute track enclosing the Roman hours and twin subsidiaries for power reserve (0-56 hours) and running seconds (engraved to the centre with the Ordnance arrow) , the centre signed 'DENT LONDON, Chronometer Maker to the QUEEN, No. 2459. WITH AIRY'S SUPPLEMENTARY COMPENSATION' in a signed and numbered gimballed bowl with safety key and locking lever, the underside with sprung winding cover and stamped H.S.^1, the full plate chain fusee movement with maintaining power, the freesprung palladium helical spring to a cut and compensated bimetallic balance with diamond endstone and Airy's compensation to an Earnshaw type spring detent escapement The case 16cms (6.25ins) wide.