This section is from the book "The Home Cyclopedia Of General Information", by Charles Morris. Also available from Amazon: Home Cyclopedia of Necessary Knowledge.
[L.] The term used to express the different sensations which are produced when light of different kinds enter the eye. When ordinary white light is passed through a prism (q.v.), it is decomposed into seven colored rays- violet, indigo, blue, green, yellow, orange, red. There are three primary color sensations-red, green, and violet; and the blending of these in different proportions gives rise to all the other colors.
 
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