Correspondence concerning clocks, time and the 24-hour time system, including the following material:

(1) Non-Observatory clocks

Memorandum on the history of 'Joseph Knibb', 17th-century London clockmakers, 1925.

Correspondence between Ethel M. Knocker, British Columbia, and Sir Frank Dyson regarding the history of Joseph Knibb, 1925.

(2) Non-Observatory chronographs and transits

Correspondence between Sir Harold Spencer Jones and the Mercantile Marine Department, 1937, regarding a memorandum submitted by the Government of the U.S.A. for consideration at the International Radio Communications Conference to be held at Cairo in February 1938.

Extract, in French, from the 'Propositions Pour La Conférence Internationale Des Radiocommunications Du Caire 1938', 1937.

(3) Greenwich time signals

Correspondence with the Director of the B.B.C. (Time Signals) regarding the 6 pips, 1939.

Correspondence between G.A. Tomlinson and H. Spencer Jones regarding the Rugby Time signal, 1937.

Correspondence between H. Spencer Jones and the Hydrographer regarding work done for the General Post Office and the B.B.C., 1937.

(4) Miscellaneous

Correspondence with the Hydrographer regarding German pocket sundials, with remarks by R. Atkinson on the same, 1946.

Correspondence between Thomas Mercer, watchmakers, and H. Spencer Jones regarding the purchase of continental watches, 1938.

Press cutting from 'The Times', 22 November 1938, regarding the 60th anniversary of the invention of standard time and the inventor, Sir Sandford Fleming, 1938.

Correspondence between the Synchronome Company Ltd and H. Spencer Jones regarding the testing of 'two very fine free pendulum installations' for Russia and La Plata, 1938.

Correspondence between R.C. Hayes, Dominion Observatory, and H. Spencer Jones regarding radio time signals, 1937.

Reference sheet sent from the Hydrographer to Spencer Jones regarding a 'Hydrographic Report on Tristan da Cunha', with a sketch on time, 1937.

(5) Adoption of 24-hour time system

Correspondence with Lord Lamington regarding support for the adoption of the 24-hour time system, 1940.

Correspondence between H. Spencer Jones and the editor of the 'Sunday Times' regarding the 24-hour time system, 1940.

Correspondence between Lord Lamington and H. Spencer Jones regarding twenty-four hour time, 1937.

Correspondence with Colonel Gordon regarding his support for the adoption of the 24-hour time system, 1934.

Memorandum on the advisability of adopting the 24-hour system, 1934.

Correspondence with T.P. Godfrey regarding his disapproval of the 24-hour time system, 1934.

Circular regarding the B.B.C.'s intention to introduce the 24-hour time system from 22 April 1934.

Correspondence between the Administration Controller of the B.B.C. and H. Spencer Jones, 1934.

Correspondence between Lord Lamington and Spencer Jones regarding 24-hour time, 1934.

List of the Bills in progress in the House of Lords in February 1934.

Correspondence between Lord Newton and H. Spencer Jones regarding the 24-hour time system, 1933.

Correspondence with Lieutenant P.W. Woodriffe regarding the 24-hour clock, 1933.

Correspondence with the editors of 'The Electrician', 'Modern Transport' and 'The Times' regarding 24-hour time, 1933.

Correspondence between W. Alfred Parr, President of the British Astronomical Association, and Spencer Jones regarding support for the introduction of the 24-hour time system, 1933.

Correspondence between Spencer Jones and the editor of 'The Times' regarding the introduction of the new system, 1933.

Correspondence between Sir Frank Dyson and A. de V. Leigh regarding the 24-hour timetable, 1929.