Page:A Treatise on Painting.djvu/254

  extremities of any object on the side which receives the light, will appear darker if upon a lighter ground, and lighter if seen upon a darker ground. But if such body be flat, and seen upon a ground equal in point of light with itself, and of the same colour, such boundaries, or outlines, will be entirely lost to the sight.   contrasted with a light ground will appear much more detached than those which are placed against a dark one. The reason is, that if you wish to give relief to your figures, you will make those parts which are the farthest from the light, participate the least of it; therefore they will remain the darkest, and every distinction of outline would be lost in the general mass of shadows. But to give it grace, roundness, and effect, those dark shades are always attended by reflexes, or else they would either cut too hard upon the ground, or stick to it, by the similarity of shade, and relieve the less as the ground is darker; for at some distance nothing would be seen Rh