I. Some experiments on metallic reflection. No. III. On the amount of light reflected by metallic surfaces

Abstract

As far as I am aware the only experiments th at have been made on the amount of radiant energy reflected by metallic surfaces at different angles are those of Potter (“Edinburgh Journal,” vol. iii, 278) and Jamin (“Ann. de Chim. et de Phys.” [3], xix, 296) for light, and for radiant heat, those of Forbes (“Phil. Mag.,” [3], viii, 246) and of MM. De la Provostaye and Desains (“Ann. de Chim. et de Phys.” [3], xxx, 276. Potter used a Bouguer’s photometer; the transparent screen being made of white paper, behind which two lamps were placed, the light from one of which always fell directly upon one half of the screen, whilst that from the other either fell directly upon the screen, or after reflection from the metallic plate. The observations were made by measuring the distance at which the first lamp had to be placed in order that both halves of the screen should appear equally bright.