RECEPTION OF THE UNDULATORY THEORY. 11 7 



in favor of the theory of emission among mathematicians of emi- 

 nence. After this crisis of the war, the theory of moveable polariza- 

 tion lost its ground ; and the explanations of the undulatory theory, 

 and the calculations belonging to it, being published in the Annal:< 

 de Chimie et de Physique, of which M. Arago was one of the conduct- 

 ors, soon diffused it over Europe. 



It was probably in consequence of the delays to which we have 

 referred, in the publication of Fresnel's memoirs, that as late as De- 

 cember, 1820, the Imperial Academy at St. Petersburg proposed, as 

 one of their prize-questions for the two following years, this, " To 

 deliver the optical system of waves from all the objections which have 

 (as it appears) with justice been urged against it, and to apply it to 

 the polarization and double refraction of light." In the programme 

 to this announcement, Fresnel's researches on the subject are not 

 alluded to, though his memoir on diffraction is noticed ; they Avere, 

 therefore, probably not known to the Russian Academy. 



Young was always looked upon as a person of marvellous variety 

 of attainments and extent of knowledge; but during his life he 

 hardly held that elevated place among great discoverers which poste- 

 rity will probably assign him. In 1802, he was constituted Foreign 

 Secretary of the Royal Society, an office which he held during life ; 

 in 1827 he was elected one of the eight Foreign Members of the In- 

 stitute of France ; perhaps the greatest honor which men of science 

 usually receive. The fortune of his life in some other respects was of 

 a mingled complexion. His profession of a physician occupied, suffi- 

 ciently to fetter, without rewarding him ; while he was Lecturer at the 

 Royal Institution, he Avas, in his lectures, too profound to be popular ; 

 and his office of Superintendent of the Nautical Almanac subjected 

 him to much minute labor, and many petulant attacks of pamphleteers. 

 On the other hand, he had a leading part in the discovery of the long 

 sought key to the Egyptian hieroglyphics ; and thus the age which 

 was marked by two great discoveries, one in science and one in litera- 

 ture, owed them both in a great measure to him. Dr. Young died in 

 1829, when he had scarcely completed his fifty-sixth year. Fresnel 

 was snatched from science still more prematurely, dying, in. 1827, at 

 the early age of thirty-nine. 



We need not say that both these great philosophers possessed, in ar. 

 eminent degree, the leading characteristics of the discoverer's mind, 

 perfect clearness of view, rich fertility of invention, and intense love 

 of knowledge. We cannot read without oreat interest a letter of 



o o 



