A mid 20th Century Swiss lever gimbaled marine chronometer by Longines. Damascened nickelled three quarter plate keyless centre seconds movement with going barrel. The plate marked "Longines Watch Co. Twenty one jewels Adjusted to Temperature and Five Positions". Plain cock with polished steel micrometer regulator, uncut balance with screws, elvinar overcoil hairspring. Club foot lever escapement, escape and lever pivots with endstones. Large signed silvered dial, large Arabic numerals for the time and a smaller chapter for centre seconds. Sector for 36 hour power reserve indication, blue steel hands. Lacquered gimbaled brass bowl with screwed on weighted cover, the movement glazed. Wound and set with a large flat button at twelve o’clock. Two tier mahogany box with brass furniture. During the second world war the allies were unable to make or acquire sufficient marine chronometers to supply the demand. To ease the situation high precision pocket watch movements were pressed into service. This is an example. Longines movements were often used because, in addition to their good timekeeping, many models included up / down indications and some ran for eight days.