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filled a chair in the Faculte des Sciences de Paris, and was Assistant- 

 Professor of Mathematics applied to Physics, at the College de France. 

 The new government thought proper to establish its title to power de 

 facto by an oath of allegiance imposed upon all public functionaries, 

 even on those who had no duty beyond that of teaching the mathe- 

 matical and physical sciences. Cauchy took refuge in Switzer- 

 land in order to preserve his loyalty to Charles X. unimpeached. 

 The presence of so distinguished a geometer in the country of the 

 Bernoullis and of Euler could not remain long concealed. The king 

 of Sardinia, informed of his voluntary exile, created for him a chair 

 of mathematics at Turin, the duties of which Cauchy discharged 

 with eclat, pursuing at the same time his other researches. Thus 

 France lost one of her most illustrious geometers, and one of the 

 most able of her Professors. In 1832 Cauchy was elected a Foreign 

 Member of the Royal Society. In the same year he was invited to 

 Prague by Charles X., to take a part in the education of the Count de 

 Chambord. He sent for his wife and two daughters, and with them 

 followed the princes to Goritz ; and during the six years devoted to 

 this honourable employment found leisure to write a multitude of 

 valuable memoirs on various parts of mathematics, which, scattered 

 throughout Germany, are not easy to obtain. He took leave of his 

 pupil in 1837, returned to France, and resumed his place in the 

 Institute, which, contrary to rule, had been left vacant, protected 

 by the admiration which the genius of its possessor inspired. 

 From this period, his studies being no longer disturbed by the duty 

 of teaching, his mathematical labours being never interrupted except 

 when engaged in works of charity, Cauchy poured forth at the 

 meetings of the Institute the inexhaustible abundance of his mathe- 

 matical genius. During the last nineteen years of his life, he com- 

 posed and published in the volumes of the Academy or in the 

 * Comptes Rendus,' more than 500 memoirs, besides a multitude of 

 reports on memoirs presented by others. Of this immense mass of 

 labour, many parts have a great value of their own ; others present 

 the initiative of ideas and of methods, which have been or will at a 

 later time be fertile. All bear upon the highest departments of 

 mathematics, the perfection and extension of pure analysis, the in- 

 vestigation and direct determination of the planetary movements and 

 of their most complicated inequalities, the theory of the undulatory 



