Correspondence with the Admiralty concerning the annual trial of deck watches, 1900.

Correspondence with the Hydrographer of the Navy concerning the shipment of chronometers and instructions on the direction of invoices, 1900-1901.

Correspondence concerning damage to chronometers in transit due to bad packing and revised instructions for packing, 1904.

Correspondence concerning the alteration in the times of the diurnal trials of chronometers and deck watches, 1905.

Correspondence concerning the number of chronometers to be purchased annually for the Navy, 1905-1906.

List of chronometers reclassified as hack watches, 1906.

Correspondence with the Hydrographer of the Navy concerning the irregularity by second and minute hands in hack watches, 1907.

Correspondence on the proposed purchase of stop-watches in place of pocket chronometers, 1905-1909.

Correspondence concerning Lindgvist's electric tape chronograph, including two test tapes from the chronograph, 1905-1909.

Correspondence with horologists concerning the purchase of stop-watches, 1905-1909.

Correspondence concerning the trial of Lindgvist's chronograph No. 3 and Arnold No. 502, including two test tapes from the chronograph, 1911.

Correspondence with the Hydrographer of the Navy concerning the scarcity of room for deck watches and chronometers at the Royal Observatory, including details of the number of watches which the Royal Observatory tests each year, 1912.