58 Xotes on the Life of Arago. 



Numerous researches, experiments, and inventions, have 

 immortalized his name ; but his principal claims to renown, 

 are, 1st, magnetic and rotatory polorization ; 2c?, magnetism 

 by the action of currents ; 3c/, magnetism by rotation. Fran- 

 cois Arago was an encyclopaedic genius. Sciences, letters, 

 social economy, — his vast intelligence embraced all with an 

 ever equal superiority. At the Ecole Polytechnique, the 

 Academie, the Observatoire, and the Municipal Council, the 

 extent and variety of his knowledge, and especially the as- 

 tonishing faculty of assimilation, vulgarization, and applica- 

 tion, with which he was gifted, placed him everywhere in the 

 first rank. As an orator, he was distinguished by a marvel- 

 lous lucidity of exposition — by the abundance, facility, and 

 picturesque energy of his delivery. As a writer, he was dis- 

 tinguished by clearness, elegance, and a sustained firmness 

 of style — qualities which place him on a par with the most 

 distinguished of our prose writers. " He possessed," says 

 Timon, " the secrets of the language, as well as the secrets 

 of the heart." " Never," says one of his biographers, " did 

 human head undertake, without breaking, such an enormous 

 mass of labour." Arago considered every man idle who did 

 not work fourteen hours a-day. Days of that kind were, 

 however, for him days of repose. He was engaged at the 

 same time in chemistry, physics, mechanics, astronomy, na- 

 tural history, philosophy, and literature. He was a member 

 of all the scientific or industrial associations in the world ; 

 his study was literally encumbered with plans to examine, 

 and memoirs to analyse. The Government, the municipality, 

 the establishments of public utility, and even private industry, 

 found in him an active and disinterested counsellor and 

 guide. His time was given to all things and to everybody. 

 At the same time that he had an eye to what passes above, 

 he had one to what takes place here ; and amidst all his ab- 

 sorbing and varied occupations he found time to shew him- 

 self one of the worthiest and most charming talkers in the 

 saloons of Paris. 



Arago's first work was read before the Institute on the 

 24th of March 1806. It was an investigation, in which he 

 was assisted by Biot, " On the Affinities of Bodies for Light, 



