This weight-driven clock employs a dead-beat escapement with jewelled pallets and the escape wheel runs in jewelled bearings. The pendulum is compensated for temperature changes using the zinc and steel method. The clock is fitted with three sets of electrical contacts capable of giving out signals at intervals of one minute, one hour and 12 hours.

For many years this clock was the time standard at the Chart Depot at Singapore. After the Japanese occupation the clock mechanism and pendulum were shipped back to the UK but the original case was lost. After the Second World War, the clock returned to Singapore where the present case was manufactured. When the Singapore base finally closed, the clock returned to the Hydrographic Office, UK in 1979 for safe keeping.

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. He had moved to a permanent address at 105 Liverpool Road, N1 by 1870. During his lifetime Kullberg gained many medals and awards for his work 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. They were 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.