Carle David TolmŽ Runge
Aug 30 1856 - Jan 3 1927Born Bremen, Germany. Died Göttingen, Germany.

Runge worked on a procedure for the numerical solution of algebraic equations and later studied the wavelengths of the spectral lines of elements.
At the age of 19, after leaving school, Runge spent 6 months with his mother visiting the cultural centres of Italy. On his return to Germany he enrolled at the University of Munich to study literature. However after 6 weeks of the course he changed to mathematics and physics.
Runge attended courses with Max Planck and they became close friends. In 1877 both went to Berlin but Runge turned to pure mathematics after attending Weierstrass' lectures. His doctoral dissertation (1880) dealt with differential geometry.
After taking his secondary school teachers examinations he returned to Berlin where he was influenced by Kronecker. Runge then worked on a procedure for the numerical solution of algebraic equations in which the roots were expressed as infinite series of rational functions of the coefficients.
Runge published little at that stage but after visiting Mittag-Leffler in Stockholm in September 1884 he produced a large number of papers in Mittag-Leffler's journal "Acta mathematica" (1885).
Runge obtained a chair at Hanover in 1886 and remained there for 18 years. Within a year Runge had moved away from pure mathematics to study the wavelengths of the spectral lines of elements other than hydrogen (J J Balmer had constructed a formula for the spectral lines of hydrogen.)
Runge did a great deal of experimental work and published a great quantity of results. He succeeded in arranging the spectral lines of helium in two spectral series and, until 1897, this was thought to be evidence that hydrogen was a mixture of two elements.
In 1904 Klein persuaded Göttingen to offer Runge a chair of Applied Mathematics, a post which Runge held until he retired in 1925.
Runge was always a fit and active man and on his 70 th birthday he entertained his grandchildren by doing handstands. However a few months later he had a heart attack and died.