Copy letter from Herbert Rix, to Frank Watson Dyson 'Dear Sir, I am sending you by this post by order of Lord Rayleigh your MS. [manuscript] to carry out some alterations about which, I understand, his Lordship has already written to you. With the MS. I have enclosed a printed paper of instructions. Please attend to these. Yours truly H Rix Asst Sec RS [Assistant Secretary, Royal Society]'. 7 July 1893