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 the use galvanic signals to determine longitude. The papers describe the attempts to establish the longitude of the Edinburgh, Oxford and Cambridge Observatories by observing set stars and taking the difference between the local time and the Greenwich Time received by telegraphic signal. Other centres included in the project, but not necessarily tested, were Liverpool, Dublin, Vienna, Bristol and Lowestoft. The papers include correspondence with C.P....