Letter from Henry E [Enfield] Roscoe, Manchester, to T E [Thomas Edward] Thorpe, Para, [Brazil] Approves of Thorpe's travel arrangements and hopes that he will have interesting results on his return in August. He has sent a second bottle of silver solution and salted paper via the 'Jerome', with some fixed but uncalibrated strips. Balfour Stewart has arranged to have his experiments made elsewhere. Thorpe's carbon dioxide results are interesting. He pleads that Thorpe should make series of daily photochemical observations on his return voyage. His assistant Jones has determined the atomic weight of vanadium. They are preparing pure chloride and have got 'some very queer reactions'. Comments on his Royal Institution lecture and gives personal and university news. 12 May 1866