361 



On the 17th of September, 1809, Arago was nommated to suc- 

 ceed Lalande as member of the Academy of Sciences by forty-seven 

 out of fifty votes. He was then only twenty-three years of age. 



A short time after Arago's admission into the Institute, he was 

 appointed professor at the Polytechnic School, where, on account of 

 the variety and extent of his knowledge, he was able to give success- 

 ively five courses on different subjects. He was also chosen Exa- 

 miner of the Engineer and Artillery officers leaving the School of 

 Application at Metz. In 1812 the Bureau of Longitudes appointed 

 Arago to give a course of lectures on astronomy at the Observatory, 

 and this course was continued until 1845 ; a more eloquent 

 expounder of the truths of science was never heard within these or 

 any other walls, and crowded audiences from every class of society 

 followed, with profit and pleasure, the facile expositor of subjects so 

 difficult. It was justly said by the present ruler of France, when in 

 his captivity at Ham, that Arago " possessed, in a high degree, those 

 two faculties so difficult to meet in the same man; that of being the 

 grand priest of science, and of being able to initiate the vulgar into 

 its mysteries." 



In 1821, Arago was engaged in making geodesical observations 

 on the coasts of France and England, and in 1822 he was nominated 

 member of the Bureau of Longitudes. The notices, which from 

 1824 to the present time, Arago furnished to the Annuaire of the 

 Bureau of Longitudes, for the instruction of the unlearned public on 

 various important points of science, are perfect models of what such 

 writings should be. In the words of M. Combes, President of the 

 Academy, " They will always be reperused with the same pleasure 

 by men of science and by the ordinary reader ; in them we find an 

 admirable clearness, with an erudition as correct as it is extensive, 

 and joined thereto, the most rigorous accuracy in the statement of 

 the phenomena, and the consequences which result from them." 



On the 7th of June, 1830, Arago obtained the honour which he 

 valued the highest, being elected to succeed Fourier as Perpetual 

 Secretary of the Academy of Sciences. He received on this occasion 

 thirty-nine out of forty-four votes. 



After the revolution of 1830 broke out, Arago entered into poli- 

 tical life ; he was elected deputy for his native department, and 

 became a member of the Municipal Council of Paris. In both these 

 capacities he had many opportunities of rendering service to science 

 and advancing public improvements. 



The revolution of 1848 evolved another change in the fortunes of 

 Arago ; he became one of the members of the Provisional Govern- 

 ment, and was nominated Minister both of the Marine and of War. 

 On his retirement from these onerous offices, for his services in 

 which he never made the slightest demand upon the national trea- 

 sury, disheartened with the state of public afiTairs, he entirely relin- 

 quished politics, and devoted himself with renewed ardour to his 

 duties as Secretary of the Academy; he commenced putting in order 

 and perfecting his numerous unpublished researches, and continued 

 to do so until increasing infirmities prevented him. In May 1852 



