Therefore in selecting two hues between each two standards, rather than a larger number, the simplest nomenclature possible is secured, and one in which no mental effort is necessary to recall the color indicated by each symbol. For example, we have four colors indicated as R, OR, RO, O; red, orange-red, red-orange, orange; or more extended, red, orange hue of red, red hue of orange, orange. Thus by using as symbols familiar terms, no effort of the memory is required to recall the color indicated by each symbol, as would necessarily be the case if there were a greater number of hues and therefore more arbitrary symbols.
The use of rotating color disks on the wheel and the top by which an infinite variety of intermediate hues can be made and accurately named by the pupils reduces the required number of papers to those types necessary for first primary work, and thus prepares the child for the use of pigments at an earlier age than would be possible without such color instruction.
The second section of the sample book contains white, black and grays as indicated on the separating fly leaf. In these the best pigmentary expression of black and white are furnished. In material colors as found in industrial products, there are various so-called blacks and whites. For black there are blue-black, green-black, and brown-black; and in white, cream-white and pearl-white. Cream-white is a yellow-white and pearl-white a blue-white. In fine white papers either blue, red or yellow is generally added to the pulp to counteract or cover up the gray tone of the natural material. The standard black here presented is the best possible pigmentary imitation of a very deep black hole, as for example, the projecting end of a large iron water or sewer pipe of considerable length buried in the ground, which is the blackest thing known.
The white is an imitation of new-fallen snow. Neither of these standards can be very nearly approached although we often hear of things as "white as snow" and as "black as night." In the same group and following the black and white are two examples each of the four kinds of grays: Green gray, warm gray, cool gray and neutral gray. A pure white in shadow is the true neutral gray and a perfect imitation of this is made by the rotation of combined black and white disks on the color wheel. If to the black and white disks we add a blue disk we have cool grays. With red, orange or yellow the warm grays are produced, while the use of a green disk gives green grays. In the papers two tones of each gray are furnished.
The papers found in the first two sections comprise all the colors necessary for earliest primary color instruction, and should become familiar to the children before explanation is made of the colors in the succeeding collections.
In the third section, designated "Broken Spectrum Scales" will be found a collection of gray colors or broken colors. As has before been stated, a broken color is a pure color mixed with a neutral gray. In the combination of pigmentary colors a tint of a color is the pure color mixed with white, a shade is the color mixed with black, and a broken color is a pure color mixed with both black and white, which is a neutral gray. Therefore if with red, for example, we mix a certain amount of a given neutral gray and call that the normal tone of a broken scale of red, for the tint in that scale we must mix with the standard red a lighter gray and for the shade a darker gray.
When a comparatively small quantity of neutral gray is combined with a pure color the result is a "gray color," as above described, because the color is quite definitely retained, but more or less modified by the gray. On the other hand, if a relatively small quantity of color is added to a neutral gray, the resulting color is properly called a "colored gray," because it is still a gray modified by color, and in this class we have warm grays, cool grays, etc., according to the color combined with the gray. The gray colors are quite generally termed "broken colors" and this seems a very useful practice, because it avoids the confusion of the somewhat similar terms "gray color" and "colored gray."
By reference to the Chart of Broken Spectrum Scales on Page 41 it will be seen that we have only twelve scales and but three tones in each scale, instead of eighteen scales and five tones, as in the pure scales, for which there is a good reason.
For educational purposes in the elementary grades, which is the only place where there is a legitimate use for colored papers, the steps in gradation of hue or tone must not be too short, and if the saturation or intensity of the normal colors in the several scales is reduced by adding gray, as in the broken colors, there is not the possibility for as many steps in either hues or tones without leaving those colors adjacent to each other too nearly alike. Therefore in the broken colors there are but thirty-six, instead of ninety, as in the pure scales.
The distinction between pure colors with tints and shades, and broken colors in various tones, should be made very plain to the children whenever the subject is brought to their notice, because it is a vital point in the classification of colors. Educationally this is one of the most objectionable features in the old red, yellow and blue theory of color composition, because no distinction is observed between pure and broken colors in classification. In the Bradley colored papers the distinction is made very decided for educational purposes, so that no one would for a moment tolerate the mixture of the normal colors from the pure scales with the normal colors from the broken scales in the formation of a spectrum.