8. The theory that red and yellow make orange, and that a red and blue make violet, is correct; but if one attempts to demonstrate the theory with pigments, one is confronted not only by the lack of standard manufactured colors but by impurities, adulterations and chemical reaction in the pigments. The adulteration may not be perceptible in one primary color, but it is manifest when that color is brought into action with another primary, for it is seldom that a pure secondary results.
COLOR NOMENCLATURE—HARMONIES
9. Color nomenclature includes primary, secondary and tertiary colors, and innumerable hues, shades and tints. All these colors bear relations to one another, either relations of analogy, or relations of contrast. (See [¶ 18 and ¶ 19].)
The [Circle Diagram I] shows the manner in which the various colors are formed. (See also [Diagram III].)
