Catalogue description Records of the Hydrographer of the Navy, and Royal Greenwich Observatory

The post of Hydrographer of the Navy was created in 1795. He became responsible to the First Sea Lord for producing charts, 'Sailing Directions', 'Notices to Mariners', tide tables and light lists and for supplying chronometers, compasses and other scientific instruments to HM ships. He was also responsible for naval meteorology and for the Admiralty's links with the Meteorological Office.

Between 1856 and 1862 there was a combined Hydrographic and Harbour Department, the work of the Harbour Branch being transferred to the Board of Trade on 1 January 1863.

A Compass Branch, associated with the Hydrographic Department was formed in 1842; in 1911 it was decided that this branch should be affiliated to the Controller's Department and that its work in connection with terrestrial magnetism should be transferred to the Royal Observatory. Since 1820 the Hydrographer had been responsible for the Observatory, being advised by a Board of Visitors.

The Hydrographer's Department at Taunton has been appointed a place of deposit for its own records under the Public Records Act 1958 while Cambridge University Library is a place of deposit for the records of the Royal Greenwich Observatory.