Copy letter from Robert William Frederick Harrison, to Professor John Newport Langley, Fellow of the Royal Society Following the Council of the Royal Society's resolution to invite Langley to deliver the Croonian Lecture, Harrison writes to ask if Langley will accept the invitation, to ask for the title of his lecture, and to enquire as to the most convenient date towards the end of that term. He notes that the lecture will occur on one of the days appointed for the meetings of the Society. 22 January 1906