Alfred George Greenhill

Sir Alfred George Greenhill was a British mathematician, born in London on 29 November 1847 and died there on 10 February 1927. He was educated at Christs Hospital School and went to St Johns College, Cambridge, in 1866. In 1876 he was appointed professor of mathematics at the Royal Military Academy at Woolwich, a chair he held until his retirement in 1908, when he was knighted. His 1892 textbook on applications of elliptic functions is of acknowledged excellence, and he was one of the leading experts in the world on applications of elliptic integrals in electromagnetic theory. In 1879 he calculated twist rate formulas for rifled artillery by approximating the projectile as an elongated ellipsoid of rotation in an incompressible fluid, and the resulting Greenhill formula, simplified for lead-core bullets, is still used today. He was a plenary speaker at the International Congress of Mathematicians in 1904 at Heidelberg and an invited speaker in 1908, 1920 and 1924.