Correspondence and related papers on the time signals at Portsmouth, Devonport and Sheerness and the tests, errors and running of time balls at Gravesend, Newcastle, Liverpool, Glasgow, Mauritius and the Cape of Good Hope. The papers include a newspaper cutting from 'The Gateshead Observer' on the importance of time balls; accounts and reports on the Post Office clocks; papers on the regulation of the London Bridge and Westminster Great Clock; and papers on the regulation of the Edinburgh Cannon signal. The correspondents include J. Washington, C.V. Walker, J.C. Clark, J.P. Nichol, C.F. Varley and W. De La Rue.