A mid-19th-century English two-day marine chronometer by Dent, fitted with Airy’s bar and housed in a mahogany box. The full-plate brass key-wind fusee movement has four turned pillars with blued-steel screws and is engraved with the broad Ministry arrow. It features Harrison’s maintaining power, a blued-steel click and spring, blued-steel barrel ratchet wheel, and double-toothed click on the barrel bridge.

The chronometer has a plain brass cock with diamond endstone, a two-arm compensation balance with circular weights and timing nuts, and an Airy’s bar with two smaller weights. It is fitted with a freesprung palladium helical hairspring and an Earnshaw spring detent escapement with endstone-fitted escape pivots. The movement is secured to the gilt dial plate with three blued-steel screws.

The signed and numbered silvered brass dial includes subsidiaries for seconds and power reserve, Roman numerals, blued-steel hands, and a broad Ministry arrow in the seconds dial. The signed and numbered brass bowl has a sprung dust cover to the winding aperture, a screw brass bezel with flat glass, and brass gimbals with locking mechanism. A numbered brass ratchet key is included.

The chronometer is contained in a two-tier mahogany box, the upper lid removed as commonly found on Ministry-issued instruments, and fitted with a signed and numbered circular plaque bearing the broad arrow and folding brass handles.