Copy letter from Robert William Frederick Harrison, to Rasmus Anderson, 2 Queen Square Place, Bloomsbury, W.C. 'Dear Sir, I have to acknowledge your letter with reference to your invention, but, as the Royal Society is concerned only with pure science, I have to return your photographs herewith [not enclosed]. I am, Yours faithfully, Robt Harrison Asst. Sec. R.S. [Assistant Secretary of the Royal Society]'. 22 January 1898