Edward Massey of London obtained at least six British patents on logs and other nautical measuring instruments between 1802 and 1848. The first described the first successful mechanical log. John Edward Massey designed and manufactured mechanical logs in the 1870s. Another relative, Thomas Walker, designed and manufactured logs in Birmingham.Ref: J. A. Bennett, The Divided Circle. A History of Instruments for Astronomy, Navigation and Surveying (Oxford, 1987), pp. 190-191.
G. Clifton, Directory of British Scientific Instrument Makers, 1550-1851 (London, 1995), p. 183.
