Copy letter from Robert William Frederick Harrison to E J Stuart, 9 Park Crescent, Worthing 'In turning over the papers left here by Sir Joseph Larmor, who retired last year from the Honorary Secretaryship of the Society, I found a letter of yours dated last March, referring to some photographs of spectroscopic lines and enclosing a memorandum explaining them. So far as I can ascertain, the photographs were returned to you shortly after the receipt of your letter, but the explanatory memorandum appears not to have gone with them. I therefore return it now and shall be glad to hear of its safe receipt.' 20 January 1913