Copy letter from Herbert Rix, to Victor Herbert Veley, University College, Oxford 'Dear Sir, We shall be glad to assist you in your rehearsal with the lantern at 2.30 next Thursday. We have not any arrangement for cutting off the heat rays, but I understand you to say that you can bring this with you. Yours faithfully, H Rix Asst. Sec. R.S. [Assistant Secretary, Royal Society]'. 3 June 1889