A Treatise on Painting/Chapter 195
Chap. CXCV.—How, in drawing a Face, to give it Grace, by the Management of Light and Shade.
A face placed in the dark part of a room, acquires great additional grace by means of light and shadow. The shadowed part of the face blends with the darkness of the ground, and the light part receives an increase of brightness from the open air, the shadows on this side becoming almost insensible; and from this augmentation of light and shadow, the face has much relief, and acquires great beauty.