Copy letter from Robert William Frederick Harrison, to Gustav Mann, Physiological Laboratory, Oxford 'Dear Sir, I shall be much obliged if you will be good enough to return the apparatus which was lent to you for the purpose of your Soirée exhibit. It has to be handed over to the custody of the Government Grant Department. I am, Dear Sir, faithfully yours, Robt [Robert] Harrison Asst. Sec. R.S. [Assistant Secretary, Royal Society]'. 7 June 1904