Copy letter from Herbert Rix, to Dr F W Mott, University College Hospital, Gower Street 'Dear Sir, Dr [Michael] Foster desires me to write and ask you kindly to return the proof of your article which you lent to him a few days ago, and which he sent back to you with his letter. Will you kindly send it to this address? I am, yours faithfully, H Rix Asst. Sec. RS [Assistant Secretary, Royal Society]'. 3 July 1891