Gustav Wiedemann. 41 



GUSTAV WIEDEMANN. 1826-1898. 



GUSTAV HBINRICH WIEDEMANN was born in Berlin in October, 

 1826. Before he was two years old, his father died, and he was 

 scarcely fifteen when he lost his mother also. He was thus from an 

 early age thrown much upon his own resources, but the care of friends 

 secured for him a careful classical and scientific education. His 

 inclination to the special study of physics, seems to have been largely 

 due to the influence of Seebeck, who, for several years, was one of 

 his teachers at the Cologne Gymnasium. From Cologne he proceeded, 

 in 1844, to the University of Berlin, where he entered upon a serious 

 course of study of 'mathematics, under Dirichlet and Joachimstal, and 

 attended the chemical lectures of Heinrich Eose, and worked practic- 

 ally at chemistry in the private laboratory of Sonnenschein. Later he 

 attended the lectures of Dove, Magnus, Mitscherlich and others. 

 When he entered the University, he had already decided to devote 

 his life to the cultivation of physics, but he considered a sound know- 

 ledge of mathematics and chemistry to be an essential preliminary 

 qualification. He took his Doctor's degree in 1847, choosing as the sub- 

 ject of his thesis an investigation in organic chemistry, involving the 

 discovery of biuret, a produce of the decomposition of urea. It is 

 significant of the changes that have occurred during the last fifty 

 years, that when Wiedemann was a student at Berlin, there were no 

 University lectures on mathematical physics, and no University labora- 

 tory for experimental physics. The liberality and zeal of Magnus, 

 however, went far to supply the latter defect ; he admitted students 

 whom he thought sufficiently promising to work in his private labora- 

 tory, and encouraged them to attend the "Physical Colloquies," or 

 evening meetings for the discussion of questions of physical interest, 

 which he established in his own house. Wiedemann shared in these 

 privileges, and thus becattie acquainted with Helmholtz, his intimate 

 friendship with whom was interrupted only by death ; he was also one 

 of the band of strenuous young physicists, who about this time founded 

 the Physical Society of Berlin. In 1850 he obtained the licentia docendi 

 from the University of Berlin, and gave lectures as a Privatdocent on 

 special branches of physics simultaneously with Beetz and Clausius. 



In 1854 Wiedemann accepted a call to the Professorship of Physics 

 in the University of Basel, where he remained till 1863, when he 

 removed to Brunswick as Professor of Physics in the Polytechnicum. 

 Three years later he was called to the Carlsruhe Polytechnicum to 



