union of white and black disks, and should be early presented in this way, because this is the only means by which we can secure standards for pigmentary neutral grays, and the fact that this special and peculiar gray is so important in all color investigation furnishes sufficient argument for making it prominent before the other grays.
Even at this early period in his color education a child may be shown that white in shadow is a gray, and the fact that it is a neutral gray is not essential to him, as he has no knowledge of any other gray and probably it may not be desirable to call attention to the various classes of grays until after the broken colors have been studied. A sheet of white card or heavy paper may serve to show that white in shade or shadow is a gray.
For this experiment fold the card or paper very sharply and hold it with the folded edge vertical and projecting toward the class, and in such a position relative to the windows that half of the paper is in very full light and the other in shadow.
A comparison of neutral gray paper No. 1 with a true shade of white or white in shadow, as explained on Page 36, will serve to connect the gray papers with the shades of white. After the idea of tones is made clear to the children, so that they can readily form the six standard scales in three tones, the completing of the Chart of Spectrum Scales in three tones will be merely a matter of drill, as no new principles are involved.
When the pupils can lay the Chart of Pure Spectrum Scales, in three tones correctly, the thoughtful teacher will naturally ask herself what is the next logical step, and it may at first seem as though the completion of the chart in five tones ought to immediately follow. But it is very desirable that the pupils begin as early as possible to make a practical application of their knowledge of colors to the familiar objects around them; and it is evident that before any very accurate comparison of miscellaneous colors can be intelligently undertaken the child
