Letter from W J [William John] Johnston, 12 South Marine Terrace, Aberystwyth, to [Joseph] Larmor He should have acknowledged receipt of his manuscript with Larmor's notes and suggestions sooner. He has taken Kopff's treatise and Einstein's Princeton lectures from the Library. He intends to produce a paper of 15 pages for the Royal Irish Academy and he thanks Larmor for reading his manuscript and the improvement to page 18. He discusses the use of generalized relativity, and the new notion of time in the special theory which deserves a more thorough examination. He thinks that the velocity of light might change by infinitesimal amounts, determined by the Michelson experiment. 6 November 1923