APPENDIX. 



" In 1796, Count Rumford presented to the Royal Society of London 

 1000, the interest of which was to be spent in striking two medals, 

 both in the same die, one of gold and one of silver, of the value of the 

 interest of the donation for two years, and to be given biennially for the 

 most important discovery or improvement relating to light and heat that 

 had been made during the preceding two years in any part of Europe." 



At the same time Count Rumford made " a corresponding donation 

 to the American Academy of Arts and Science of $5000, the interest of 

 which was to bo used in like manner as regards American discoveries. 

 It was provided that if this term passed without any discovery or im- 

 provement being made that should be deemed worthy of the award, the 

 accruing interest was to be added to the principal, and the augmented 

 income thus arising was to be added to the medals when the next award 

 was made." 



The Royal Society accepted the trust, and made the first award to 

 Rumford himself in 1802; in 1804, to Leslie; in 1806, to Murdock ; 

 in 1810, to Malus; in 1814, to Wells; in 1816, to Davy; in 1818, to 

 Brewster; in 1824, to Fresnel; in 1834, to Melloni; in 1838, to Forbes; 

 in 1840, to Biot ; in 1842, to Fox-Talbot ; in 1846, to Faraday ; in 1848, 

 to Regnault ; in 1850, to Arago ; in 1852, to Stokes ; in 1854, to Arnott; 

 in 1856, to Pasteur; in 1858, to Jamin ; in 1860, to Clerk-Maxwell; in 

 1862, to Kirchhoff; in 1864, to Tyndall ; in 1866, to Fizeau; in 1868, 

 to Balfour Stewart, etc. 



These awards covered the most important discoveries that had been 

 made in relation to heat and light the production of heat by friction, 

 the correlation of forces, the effects of surfaces on radiation, the polari- 

 zation of light, the theory of the formation of dew, the transverse vi- 

 brations of light, the application of the thermopile to the study of radi- 

 ant heat, the refraction of dark rays, the invention of photography, the 

 discovery of fluorescence, the fixed lines of the spectrum, the distribution 

 of heat in the spectrum, the velocity of light, etc. 



The American Academy permitted several years to pass without mak- 

 ing any award. Meantime the fund had so greatly increased that the 



