As we have discussed line and mass composition as balanced over the central vertical line, so is the question of light and shade best comprehended, as forces balancing, over a broad _middle tint._ The medium tint is the most important, both for tone and color. This commands the distribution of measures in both directions; toward light and toward dark. Drawings in outline upon tinted paper take on a surprising finish with a few darks added for shadow and the high lights touched in with chalk or Chinese white. The method in opaque water color, employed by F. Hopkinson Smith and others, of working over a tinted paper such as the general tone of the subject suggests, has its warrant in the early art of the Venetian painters. If a blue day, a blue gray paper is used; if a mellow day, a yellow paper.
In pictorial art the science of light and dark is not reducible to working formulae as in decoration, where the measures of _Notan_ are governed on the principle of interchange. Through decoration we may touch more closely the hidden principles of light and shade in pictures than without the aid of this science, and the artist of decorative knowledge will always prove able in “effect” in his pictorial work.
With that clear conception of the power of the light and the dark measure which is acquired in the practice of “spotting” and filling of spaces, especially upon a middle tint, the problem of bringing into prominence any item of the picture is simplified upon the decorative basis.
Pictorially the light measure is more attractive than the dark, but the dark in isolation is nearly as powerful.
With this simple notion in mind the artist proceeds upon his checker-board opposing force to force.
With him the work can never be as absorbing as to the decorator whose items are all of about the same value and of recurring kinds. The subject dictates to the painter who must play more adroitly to secure an effect of light and shade by the use of devices such as nature offers.
As a matter of _brilliancy of light,_ with which painting is concerned, the effect is greater when a small measure of light is opposed to a large measure of dark than when much light is opposed to little dark. Comparison between Whistler’s “Woman in White,” a white gown relieved against a white ground, the black of the picture being the woman’s hair, and any one of the manger scenes of the fifteenth century painters with their concentration of light will prove how much greater the sense of light is in the latter.