In an elaborate chart of colors highly recommended for primary color instruction a dozen years ago no correct understanding of the classification of colors is shown, the tints and shades being indicated by a very decided change of hue rather than a consistent modification of tone. For example, in the red scale the standard or normal red is vermilion, i.e., an orange red; shade No. 1 is simply a red less orange in hue than the standard, and shade No. 2 a shade of the standard red advocated in this system; while tint No. 1 is a broken yellow orange and tint No. 2 is much more yellow and more broken than No. 1.
Similar inconsistencies occur in all the other scales, showing that the author had no correct knowledge of the analysis of colors, and yet this was the best and practically the only aid offered for instruction in color at that time.
Neither were there any true standards for neutral grays and the term "neutral" was used in such an indefinite way as to rob it of all actual value, until by the aid of disk combinations it came to be confined to white in shadow as closely imitated by the combinations of white and black disks.
Fig. 9.
With colored papers made in imitation of the six standards and two tints and two shades of each, six scales of colors may be produced by arranging the five different tones of each color in a row, as in Fig. 9, which represents the orange scale with tints at the left and shades at the right. If, in addition to these six scales, we have two scales between each two of the standards, we may have between the orange scale and the yellow scale a yellow orange scale and an orange yellow scale, and if we thus introduce the intermediate scales between each of the other two standards, and include the red violet and violet red, we shall have eighteen scales of five tones each.
The eighteen scales as above named may be arranged as shown in Fig. 10 to form a chart of pure spectrum scales which is very valuable for study and comparison and especially so in the study of the theory of harmonies. All these tones are called pure tones and this chart is therefore called a chart of Pure Spectrum Scales.
The idea that soft, dull, broken colors produce best harmonies when used in combination may or may not be a universally accepted truth, but there is a general belief that it is much easier to make acceptable combinations with broken colors than with pure spectrum colors and their tints and shades, and therefore the temptation has been strong to select a general assortment of colors which easily harmonize because of the pleasing effect, instead of having regard solely to the educational value of colors.
Truth in education requires that when colors are classified as spectrum colors they shall all be the nearest approach possible to the true spectrum colors, and in the spectrum there are no broken or impure colors. Therefore, whenever the spectrum is set up as nature's standard or chart of colors and an imitation is made in pigments or papers, great care should be used to secure the most accurate imitation possible, but in the past this has not been the case, because of the prevailing idea that the colors must all be possible combinations of three primaries, and hence the orange, green and violet have often been very broken colors. While pure colors and their tints and shades may be advantageously combined with various tones of broken colors in one composition for artistic effect, they should be definitely divided when classified for educational purposes, and their differences clearly explained to students.
In a scale of tones in any color the several papers will harmonize more easily if the tints and shades are not too far removed from the standard, but it is thought by many good judges that the educational advantage in learning to see the relationship of color in the more extreme tones is of greater importance in the elementary grades than the facility for making most pleasing combinations. Consequently in the Bradley colored papers the tints are very light and the shades quite dark.