Microscope Museum

Collection of antique microscopes and other scientific instruments

Sike’s hydrometer (late 19th century to the early 20th century)

Sike’s hydrometer, with a thermometer (broken; labelled T. O. BLAKE, LONDON) and ruler, dated from the late 19th century to the early 20th century. The wooden box containing the instrument is labelled ‘SIKE’S HYDROMETER, BUSS, 48 HATTON GARDEN, LONDON’, and contains also a note with the indication ‘RE-ADJUSTED BY BLAKE, JUNE 10.04’. The hydrometer and the weights are engraved with the serial number 45903. The Sike’s hydrometer is used to determine the density of a fluid, by floating the hydrometer in the fluid and noting its buoyancy from its scale. A set of weights that attach to the hydrometer is used to adjust the range of the instrument. The thermometer is used to determine the temperature at which the measurement is being made. This type of hydrometer was originally invented by Bartholomew Sikes in the late 18th century, with the objective to measure the alcoholic content of a liquid. The success of the device caused his name to be immortalised in an Act of the UK’s Parliament (the Sikes' Hydrometer Act 1816), and the Sike’s hydrometer was the standard approach in the UK to measure the alcohol proof of spirits from 1816 until 1980. Thomas Odempsey Buss (1797 – 1879) or simply Buss is a common name associated with hydrometer sets. Buss and his successors operated at 33 Hatton Gardens from 1866 – 1895, and at 48 Hatton Garden from the 1890's. T. O. Blake established his business in 1905.

LAST EDITED: 02.10.2022