Autograph Letter Signed ‘H.E.Roscoe’, to G.W.Rawlins, about the filter pump Roscoe has sent him. A good one page example, 8 x 5 inches. The Owens College, Manchester, 28 June 1875. Sir Henry Enfield Roscoe (1833-1915), chemist, professor of chemistry at Manchester (1857-1886), worked on the preparation and properties of pure vanadium. He was the grandson of the historian William Roscoe, and uncle of Beatrix Potter. Roscoe assisted Bunsen in his research on the measurement of the chemical action of light.