Letter from Herbert Rix, The Royal Society, Burlington House, London, to Robert [William Frederick] Harrison, Assistant Secretary of the Royal Society Regarding Mr Joules apparatus, which was used by his father, Dr Joule, 'for the re-detemination of the mechanical equivalent of heat'. Enclosed is a printed letter from [George Gabriel] Stokes and [Thomas Henry] Huxley, to Dr Joule, dated 15 March 1878, concerning Joules application to the Government Grant Fund, for £200 for an 'exhaustive inquiry into the change which takes place in the freezing and boiling points of mercurial thermometers'. Includes a printed letter from Herbert Rix, dated 27 February 1888, to Dr Joule, calling attention a list of instruments. 2 November 1896