Note 6 — Chapter II · COLOR QUALITIES.
Reading edition
See Glossary for definitions of Micron, Photometer, Retina, and Red, also for Hue, Tint, Shade, Value, Color Variables, Luminosity, and Chroma.
7. See Photometer in paragraph 65.
8. See definition of White in Glossary.
9. When recognized for the first time, a middle green, blue, or purple, is accepted by most persons as well within their color habit, but middle red and middle yellow cause somewhat of a shock. “That isn’t red,” they say, “it’s terra cotta.” “Yellow?” “Oh, no, that’s—well, it’s a very peculiar shade.”
Yet these are as surely the middle degrees of red and yellow as are the more familiar degrees of green, blue, and purple. This becomes evident as soon as one accepts physical tests of color in place of personal whim. It also opens the mind to a generally ignored fact, that middle reds and yellows, instead of the screaming red and yellow first given a child, are constantly found in examples of rich and beautiful color, such as Persian rugs, Japanese prints, and the masterpieces of painting.
10. See Color Tree in paragraph 14.
11. Unaware that the spherical arrangement had been used years before, I devised a double tetrahedron to classify colors, while a student of painting in 1879. It now appears that the sphere was common property with psychologists, having been described by Runge in 1810. Earlier still, Lambert had suggested a pyramidal form. Both are based on the erroneous assumption that red, yellow, and blue are primary sensations, and also fail to place these hues in a just scale of luminosity. My twirling color solid and its completer development in the present model have always made prominent the artistic feeling for color value. It differs in this and in other ways from previous systems, and is fortunate in possessing new apparatus to measure the degree of hue, value, and chroma.
12. See Plate I.
13. See Course of Study, Part II.
14. See Chapter VI.
15. See Part II., A Color System and Course of Study.
16. See Color Study assigned to each grade, in Part II.