APrENDix. 335 



Bureau des Longitudes, and in which he made the most 

 complicated questions of science accessible to every culti- 

 vated mind, had a similar result. Finally, the political 

 part which he played in the ranks of the opposition, both 

 during the Eestoration and under Louis Philippe, con- 

 tributed also very materially to increase his reputation, 

 by making him known to many persons who took no 

 interest in science. Very few savants, and certainly none 

 in our day, have ever enjoyed during their life a more 

 widely diffused popularity. 



Arago, who in the eyes of the world in general was 

 regarded as the first of living astronomers, scarcely paid 

 any attention to astronomy properly so called. It was 

 especially as a physicist that he excelled, and in several 

 departments of natural philosophy he made important 

 discoveries. We owe to him, amongst other things, the 

 knowledge of chromatic polarisation, of magneto-elec- 

 tricity, and magnetism by rotation. He published very 

 few complete memoirs. His papers were often left 

 unfinished, whilst he also occasionally delegated to others 

 the task of accomplishing the experiments of which he 

 had conceived the general plan. With the exception of 

 his notices ande/o^e5, Arago published very little; and it 

 is probable that the forthcoming edition of his works, 

 which is now in the course of publication, will contain 

 many hitherto unpublished memoirs. 



This is not the place in which to speak of Arago as a 

 politician. Every one is well acquainted with the part 

 which he played in public affairs. He at all times took 

 his place in the extreme opposition ; but it is certain that 

 he was very ill adapted to bear the excitement of a public 

 life. After his last election as deputy, under Louis 

 Philippe, he returned home ill and suffering from the 

 agitation caused by finding that he had given occasion 

 to a popular movement, which it was feared might lead 



