Page:Popular Science Monthly Volume 14.djvu/19

 in succession, the last one will appear duller and inferior in brilliancy to the others, but it will still appear red.

Proceeding with the examination of the effects produced on the other colors, we find that orange has been moved toward yellow, and also toward the centre of the circle; hence our diagram tells us that red, when put into competition with orange, causes the latter to appear



more yellowish, and at the same time less intense. Advancing along the circumference of the circle, our diagram informs us that yellow is not much affected in the matter of saturation or intensity, but is simply made to appear more greenish. The two circles during superposition cut each other near the position of yellow; from this point onward the effect changes as far as intensity or saturation is concerned, the greenish-yellow being moved decidedly outside of the original circle as well as toward the green; it is made, therefore, by contrast with red, to appear more brilliant as well as more greenish. Green is made to appear somewhat bluish and more brilliant. Greenish-blue has been considered. Cyan-blue is made to appear slightly more greenish as well as much more brilliant; the same is true of blue, though its increase in brilliancy by contrast with red is rather less than is the case with cyan-blue. Violet has its hue considerably altered toward blue; its saturation is diminished. Purple is made to look more violet and is much diminished in saturation.

If we wish to study the effects produced on the colors of the chromatic circle by contrasting them with yellow, we have of course merely to displace the upper circle along the line joining yellow and its complement, ultramarine-blue, and then proceed as before.

It is quite evident that this contrast-diagram will furnish correct results only on condition that the colors in it are properly arranged; if the angular positions of the colors are laid down falsely, the results in the matter of increase or diminution of brilliancy will also be false.