‎"ROSCOE, HENRY E. - THE ISOLATION OF VANADIUM.‎
‎The Bakerian Lecture. - Researches on Vanadium. Received November 20, - Read December 19, 1867. (+) Researches on Vanadium. - Part II. Received June 16, - Read June 17, 1869.‎

‎(London, Taylor and Francis, 1869-70). 4to. No wrappers as extracted from ""Philosophical Transactions"" 1868 - Vol. 158. Pp. 1-27. A small tear to top of first leaf, no loss. (+) Vol. 159. Pp. 679-692.‎

Reference : 44179

‎First appearance of this importent paper in which Roscoe announces the isolation of vanadium.""The final step in the discovery of vanadium was accomplished by the English chemist, Sir Henry Enfield Roscoe...In about 1865 he found that some of the copper veins of the Lower Keuper Sandstone of the Trias in Chesire contained vanadium and that one of the lime precipitates from this ore contained about two percent of it. It was from this unpromishing material that Roscoe and Sir Edmund Thorpe laboriously prepared the pure vanadium compounds needed for a thorughout study of the element. When Roscoe investigated these compounds he found that vanadium is a trivalent element of the phosphorous group. He also discovered that what Berzelius had taken for the metal was really the mononitride, VN, and that most of the vanadium compounds studied by the Swedish chemists had contained oxygen.""(Weeks. ""Discovery of the Elements"", p. 93).‎