Most of the records retained by the Chronometer Department date to the Herstmonceux era and relate to the service, repair and overhaul of Admiralty owned chronometers at the workshop there. Many of the files bear ‘Chronometer Laboratory’ file series numbers 38 or 39 and have been grouped accordingly. A series of photographs (series 4) includes images of H1, H4 and Kendall 1 and 2, along with two sets of photographs showing the Chronometer Department and staff at Bradford on Avon during the Second World War, and later, at Herstmonceux . A notable legacy item in the collection is an early handwritten manuscript titled 'Concerning the clock', [c.1870s?] catalogued at RGO 71/1/3/1.