Copy letter from Robert William Frederick Harrison, Assistant Secretary of the Royal Society; to F. J. Selby, Secretary of the Advisory Committee for Aeronautics 'Replying to your letter of December 12th, it will be convenient for you to have the use of a room at the Royal Society for the following meetings of the Advisory Committee for Aeronautics: Aerodynamics Sub-Committee, January 7th, 2.30pm Engine Sub-Committee, January 14th, 11am Advisory Committee, January 14th, 3pm.' 13 December 1918