Prism. A triangular form of glass, or any refracting medium, by the oblique action of which the atoms whose propulsions, called light, are decomposed, and ex hibit a coloured spectrum, which is divided into 300 parts. The upper side is hot, red, and oxygenous, and 45 parts; and the lower violet, cold, and hydrogenous, and 80 parts ; with the intermediate colours and qualities, as orange 27. yellow 48, green 00, blue 60, and indigo 40. The whole being a mechanical and perfect decomposition of the elementary atoms of the atmosphere, the excitement of which constitutes, light.

Prism 373