Copy letter from Robert William Frederick Harrison, Assistant Secretary of the Royal Society; to the Secretary of the Department of Scientific Research and Experiment; Room 45 South Block, Admiralty, S.W. Expresses regret that there was no opportunity to talk to Professor McLennan, who was present at the latest Soiree meeting, before he left for Canada. Asks if, in Professor McLennan's absence, the Admiralty could arrange to exhibit something at the Soiree of May 28th. 29 April 1919