Henry Enfield Roscoe

Sir Henry Enfield Roscoe FRS (7 January 1833 – 18 December 1915) was an English chemist. He is particularly noted for early work on vanadium and for photochemical studies.

Kirchhoff, Bunsen, and Roscoe (1862)

Henry Enfield Roscoe was born in London, the son of Henry Roscoe (1800–1836) and Maria Roscoe (née Fletcher) (1798-1885), and grandson of William Roscoe (1753–1831). Stanley Jevons was a cousin.

Roscoe studied at the Liverpool Institute for Boys and University College London. He then went to Heidelberg to work under Robert Bunsen, who became a lifelong friend. He also befriended William Dittmar. In 1857, Roscoe returned to England with Dittmar and was appointed to the chair of chemistry at Owens College, Manchester, with Dittmar as his assistant. Roscoe remained at the college until 1886 by which time the Victoria University had been established. From 1885 to 1895 he was MP for Manchester South. He served on several royal commissions appointed to consider educational questions, in which he was keenly interested, and from 1896 to 1902 was vice-chancellor of the University of London. He was knighted in 1884.

Roscoe's scientific work includes a memorable series of researches carried out with Bunsen between 1855 and 1862, in which they laid the foundations of comparative photochemistry. In 1864 they carried out what is reputed to be the first flashlight photography, using magnesium as a light source. In 1867, Roscoe began an elaborate investigation of vanadium and its compounds, and devised a process for preparing it pure in the metallic state, at the same time showing that the substance which had previously passed for the metal was contaminated with oxygen. In so doing he corrected Berzelius's value for the atomic mass. Roscoe was awarded the 1868 Bakerian Lecture for this work. He also carried out researches on niobium, tungsten, uranium, perchloric acid, and the solubility of ammonia.

He was the uncle of Beatrix Potter. The mineral Roscoelite was named after him, due to its vanadium content and Roscoe's work on that element.

Roscoe received an honorary doctorate (LL.D) from the University of Glasgow in June 1901. In November 1909 he was sworn in the Privy Council. He was awarded the Franklin Institute's Elliott Cresson Medal in 1912.

Roscoe's publications include, besides several elementary books on chemistry that had a wide circulation and were translated into many foreign languages, Lectures on Spectrum Analysis (1869); a Treatise on Chemistry (the first edition of which appeared in 1877–1892); A New View of Dalton's Atomic Theory, with Dr Arthur Harden (1896); and an Autobiography (1906). The Treatise on Chemistry, written in collaboration with Carl Schorlemmer (1834–1892), who was appointed his private assistant at Manchester in 1859, official assistant in the laboratory in 1861, and professor of organic chemistry in 1874, was long regarded as a standard work. Roscoe's Lessons in Elementary Chemistry (1866) passed through many editions in England and abroad.

Selected works

• Roscoe, Henry (1876). Chemistry. New York: Appleton. 
• Roscoe, Henry (1878). Spectrum Analysis. London: Macmillan. 
• Henry Roscoe (1882) Kurzes Lehrbuch der Chemie Braunschweig : Vieweg
• Roscoe, Henry (1895). John Dalton and the Rise of Modern Chemistry. New York: Macmillan. 
• Roscoe, Henry (1906). The Life and Experiences of Sir Henry Enfield Roscoe. London: Macmillan. 

A blue plaque erected Quay Street, Manchester

The Roscoe Building at the University of Manchester was named after Professor Roscoe: it is a large general-purpose teaching facility used for various levels of teaching in Brunswick Street.