OF ARTS AND SCIENCES : MAY 27, 1862. 19 



Etrangeres; that he published eight papers in the Memoires d'Arcueil, 

 twenty-three in the Bulletin de la Societe Philomatique, fifteen in the 

 Annales de Chimie et de Physique, forty in the Comptes Rendus, four 

 in the Journal des Mines, three in the Journal Polytechnique, and one 

 each in the Connaissance des Terns and the Journal de Physique. 

 He became editor in the mathematical department of the Journal des 

 Savans in 1816, and has himself contributed largely to its pages, be- 

 sides furnishing many notices in the Bibliotheque Universelle. These 

 numerous publications only presented the fruits of great historical or 

 experimental research, often in new and difficult fields of investiga- 

 tion, ranging through every branch of Physics, Chemistry, Astronomy, 

 and Mathematics. He welcomed, in their infancy, the new-boi-n sci- 

 ences of Electro-Magnetism and Radiant Heat, and nourished them 

 from his own affluent resources. At one time we see him listening to 

 the different sounds of the same organ-pipe, when filled with various 

 gases ; at another time, he is lost in the mazes of astronomical chronol- 

 ogy, or delving among the remains of ancient Chinese science. Now 

 he is solving a problem in the attraction of spheroids, or the tauto- 

 chronous curves, or the mathematical laws of heat and sound, and 

 then, again, he is experimenting on the gases in the bladders of fishes, 

 or on the elastic force of vapors, or the eye-pieces of telescopes. He 

 handles with the same delicate touch the hypothetical atoms of chemistry 

 and the second differentials of the calculus. No speciality in the phy- 

 sics of our own globe eluded his vigilant eye. The figure of the planet ; 

 the variations of terrestrial gravity and terrestrial magnetism; the 

 multitudinous phenomena of the atmosphere, its constitution, its limits, 

 its refractions, ordinaiy and extraoi'dinary ; the aurora borealis ; mete- 

 oric stones ; — all these subjects, however incomplete they yet remain, 

 received an additional touch at his hands. But the great thought in 

 all his studies was given to theoretical and experimental optics. The 

 polarization and double refraction of light, and its applications to crys- 

 tallography, its use as a substitute for chemical analysis, and the pro- 

 duction of artificial crystallization by heat, pressure, or induration, were 

 favorite topics of study, on which he experimented largely and wrote 

 voluminously. 



The most original step which Biot took in science was when he dis- 

 covered the laws of rotatory polarization, and their application to the 

 analysis of various solutions. His labors upon this subject extend over 

 forty years of his life, and culminated in the brilliant discovery by 



