Note:  Do not rely on this information. It is very old.

Emission Theoryof Light

Emission Theory of Light, known also as the corpuscular theory, was that light consisted of extremely refined particles of material nature projected from the luminous body. If it struck certain substances it rebounded without entering; those were called opaque substances. If, on the other hand, the material was transparent, it possessed the property of allowing the light corpuscles to enter. The distinguished advocacy of Newton retarded the death of this theory and the advance of the true wave-theory of light. He explained the ordinary laws of reflection and refraction, certain phenomena of interference of light, and other observed effects, by the most ingenious assumptions of properties possessed by the light particles; but Fresnel and others by repeated experiments in diffraction and like branches of the subject cleared away the difficulties that had presented themselves to the wave-theory, and this century has seen the complete adoption of the latter.