Page:A Treatise on Painting.djvu/253

 lights and shades are by means of great distance blended together into a general half-tint; and this is the reason why trees and other objects are found to be in appearance darker at some distance than they are in reality, when nearer to the eye. But then the air, which interposes between the objects and the eye, will render them light again by tinging them with azure, rather in the shades than in the lights; for the lights will preserve the truth of the different colours much longer.   shadows between the folds of a drapery surrounding the parts of the human body will be darker as the deep hollows where the shadows are generated are more directly opposite the eye. This is to be observed only when the eye is placed between the light and the shady part of the figure.   opake body appears less relieved in proportion as it is farther distant from the eye; because the air, interposed between the eye and such body, being lighter than the shadow of it, it tarnishes and weakens that shadow, lessens its power, and consequently lessens also its relief.  Rh