Correspondence regarding the inspection, rating, supply and testing of service watches and other chronometers and clocks by the Royal Greenwich Observatory Chronometer Section, including the following items:

Correspondence regarding the irregular rates of watches in submarines during 'snorting' at sea, 1952.

Correspondence regarding tests with Ragasine oil carried out by the Chronometer Section for the International Watch Company, Schaffhause, Switzerland, 1952.

Correspondence with D.W. Fletcher regarding his work to complete the preparation of the Harrison No. 1 Chronometer for exhibition at 'the British Clockmaker's Heritage', 1953.

Correspondence regarding the loan of the chronometer Vacheron and Constantin 54842 for use by the Cambridge University Expedition to observe the total eclipse of 25 February 1951 near Khartoum.

Correspondence concerning the loan of two Paul Buhre Chronometers to the Metrology Division of the National Physical Laboratory, 1951.

Correspondence with Talbot Johns, U.S.A., regarding the service history of the Muston Chronometer No. 610, 1947.

Letters from F.W. Thorne of the Royal Navy College to the Astronomer Royal regarding damage done to the Riefler Clock No. 136, 1947.