Diagram of Values and Colors
| Wt | Wt | ||||||||||||
| HLt | R | RO | O | OY | Y | YG | G | GB | B | BV | V | VR | HLt |
| Lt | R | RO | O | OY | Y | YG | G | GB | B | BV | V | VR | Lt |
| LLt | R | RO | O | OY | Y | YG | G | GB | B | BV | V | VR | LLt |
| M | R | RO | O | OY | Y | YG | G | GB | B | BV | V | VR | M |
| HD | R | RO | O | OY | Y | YG | G | GB | B | BV | V | VR | HD |
| D | R | RO | O | OY | Y | YG | G | GB | B | BV | V | VR | D |
| LD | R | RO | O | OY | Y | YG | G | GB | B | BV | V | VR | LD |
| Blk | Blk | ||||||||||||
Definition of the Color-Terms
132. It is important that the words which we use for the different colors should be well understood, that in using them we use them with the same meanings. By Red I mean the only positive color which shows no element either of Yellow or of Blue. It is the color which we often describe by the word crimson, and we produce it by the mixture of Rose Madder and Vermilion. By Yellow I mean the only positive color which shows no element either of Red or Blue. It is the color of the primrose which may be produced by the pigment Aureolin. By Blue I mean the only positive color which shows no element either of Yellow or of Red. Blue is seen in a clear sky after rain and in the pigment Cobalt. By Orange I mean a positive color showing equal elements of Red and of Yellow. By Green I mean a positive color showing equal elements of Yellow and of Blue. By Violet I mean a positive color showing equal elements of Blue and Red. The character of the intermediates is clearly indicated by their several names. In each one we see the adjacents in equal measures. This definition of the colors is only approximate. It does not pretend to be scientific, but it may help to bring us to a common understanding. To carry these definitions farther, I should have to produce examples. This I can do in my class-room, producing each color according to my idea, exactly. I might reach the same result approximately by color-printing, but the result would not, probably, be permanent. The samples produced by hand, for use in the class-room, can be reproduced from time to time when they no longer answer to the ideas which they are intended to express. In this treatise I shall use a terminology instead of colored illustrations which would not be satisfactory, or, if satisfactory, not so permanently.