Scope and Contents Correspondence and related papers on the time signal and time ball service, including the failures of the Greenwich time signal; requests for information on time balls; the establishment of time balls or guns at Queenstown, Sheffield, Bristol and Manchester; a paper by S.P. Langley 'On the Allegheny system of electrical time signals'; experiments with the Post Office chronopher; corrections and errors of the Post Office and Westminster clocks; the system of operation employed by the London...

Scope and Contents Correspondence and papers concerning galvanism and electric clocks. The correspondents include C.V. Walker, A. Clarke, J. Muirhead, F.I. Scudamore, C. Wheatstone, C.E. Delaunay and S.P. Langley. The papers include a diagram of the gate of the electric clock at London Bridge, 6 December 1872; an extract from 'The Glasgow Daily Herald', 27 January 1866, on electric clocks and electrometers; an extract from 'The Royal Leamington Spa Courier', 17 March 1866, on C.T. Bright's electric clock;...