18ct gold open face 'Half-chronometer' pocket watch by J. W. Benson, 25 Old Bond St., London. Number 1091. Fine, signed and numbered white enamel dial, with 0-30 hour up/down dial at XII, sunken subsidiary seconds at VI, black Roman numerals, blued steel hands. Stem wind with depress to wind, hands setting tab lever under bezel at I. Plain case, monogrammed to back, internal 18ct gold cuvette. Signed and numbered 3/4 plate back, helical sprung lever escapement. Total weight 96gm The English term 'Half-chronometer' is, perhaps, a rather grandiose name for what the Americans termed an 'adjusted' watch meaning a watch adjusted for temperature. This does not mean that other watches will not cope adequately with changes in temperature but that the 'Adjusted' or 'Half-chronometer' watch has been rigorously tested at extremes of temperature and adjusted to minimise errors.