A marine chronometer numbered 6736, by Victor Kullberg. It has a two-day full-plate movement with reverse fusee, and four pillars, all fixed with blued screws. The movement is marked with the broad arrow. The fusee, with stop-work and Harrison's maintaining power, has a pipe round the winding square. There is an Earnshaw-type spring detent escapement and a two-arm balance with a helical balance spring.

The movement is mounted in a three-tier mahogany box with a push-catch for the lid and lock for the upper half. The upper half has a strut limiting opening to 90°. On the front of the upper half is screwed a rectangular tablet inscribed ‘V. KULLBERG / TWO DAYS / 6736’ with a broad arrow. The box fittings are standard, with flush handles on the sides, brass gimbals and a ratchet-winding key. The push-catch and lock are surrounded by shaped brass inserts. The underside of the box is covered with green baize. Inside the lid is a brass label-holder (empty), and in the base of the box is an applied black label reading ‘MINISTRY OF DEFENCE / HYDROGRAPHIC DEPT. / CHRONOMETER MARINE / Stores Ref. H. S. 527-3634 / Serial No. 6736’.

A silvered-brass dial has Roman numerals and a large seconds dial has Arabic ten-second figures with straight batons at alternate five-second intervals. The dial is inscribed in the centre ‘VICTOR KULLBERG, / Maker to the Admiralty, / THE INDIAN & ITALIAN GOVERNMENTS, / 105 Liverpool Rd London. N.’, and in the seconds dial, ‘TEN GOLD MEDALS AWARDED / DIPLOMA OF HONOR, SOLE & HIGHEST AWARD VIENNA’. Also in the seconds dial is the number 6736 and the broad arrow. The up-and-down dial, below XII, is marked with Arabic numerals in eight-hour intervals up to 56 and is marked 'UP' above zero and 'DOWN' above 56. Beside this dial are marks for ‘TO H.M. THE KING OF SWEDEN AND NORWAY’ and ‘GRAND PRIX PARIS 1900’. The chronometer is in fair condition.

Victor Kullberg (1824–1890) was born in Visby on the Island of Gotland, Sweden. He was trained by the Swedish chronometer maker Victor Soderburg in Stockholm in 1840 and emigrated to London in 1851, having moved to his permanent address at 105 Liverpool Road, N1, by 1870. During his lifetime Kullberg gained many medals and awards for his chronometers and enjoyed a truly international reputation. As well as supplying many foreign governments, he regularly submitted chronometers for the Annual Trials at Greenwich Observatory, gaining first place in 1864 with a chronometer fitted with his newly invented ‘flat rim’ balance.

His inventions included several designs of compensation balance and improvements to keyless winding for pocket watches. He also designed the automatic gas-governor for controlling the temperature of the chronometer testing ovens at the Observatory. More than 500 chronometers by Kullberg were supplied to the Royal Navy alone and he can be said to have been one of the 19th century’s finest chronometer makers. On Kullberg’s death in 1890 the firm was taken over by George and Peter Wennerstrom, themselves succeeded by Sanfrid Lundquist who had joined the firm in 1894 and who moved the firm to Cranford in Middlesex in 1938, trading under the name of Victor Kullberg until his death in 1947.