Copy letter from Robert William Frederick Harrison to Sir Arthur [William] Rücker, Fellow of the Royal Society 'Dear Sir Arthur Rücker, We have sent you Proc[eedings of the Royal Society] Vol 71 No 276; [Philosophical] Trans[actions of the Royal Society] A, Vol 206, No 404; also the address of Eyre & Spottiswoode (Binders). With reference to Trans A, 403, of which we have none left, I find that Messrs Dulau & Co have a copy stocked. Accordingly we are asking them to supply you with the number.' 16 November 1908