| Description | Table of mean hourly deflections in electrical currents in telegraph wires between Derby and Rugby, detected in Derby by 'deflectometer' [galvanometer]. Commencing at 1.00am on 24 May, and ending at 12.00 midnight on 29 May [1847]. Columns for time of observation, left and right deflections on each day, with a mean of each observational hour over the six day period.
Data on magnetic deflections in the Midlands was used in the paper 'On the spontaneous electrical currents observed in the wires of the electric telegraph', by W.H. Barlow, Philosophical Transactions of the Royal Society, v.139 (1849), pp.61-72.
Headed [p.1]: 'Table no.5. Mean deflections for each hour exhibited by a deflectometer at Derby in connection with a wire extending to Rugby - for the week commencing May 24th. Rugby Instrument'. Note below the main table: 'The means are taken from 12 observations in each hour. There was lightning with occasional thunder from 2 to 4 A.M. on the 29th'. |