Copy letter from Robert William Frederick Harrison, to Dr Charles Gabriel Seligmann, 15 York Terrace, Regent's Park, N.W. 'Dear Dr Seligmann, We do not appear to have your boxes of slides here. The day after the Soiree we had charge of, and returned two boxes of films belonging to Dr Hele-Shaw, but there was nothing else left. I am, faithfully yours, Robt [Robert] Harrison Assistant Secretary R.S. [Royal Society]'. 28 May 1907