The Light, striking on the Faces of Persons placed between dark Walls, makes them appear very graceful, and with a great Relievo; especially if the Light comes on them, from on high: The Reason of this Relievo is, because the most forward and advanc'd Parts of these Faces, are illuminated with the universal Light of the Air before them, so that the Parts thus enlighten'd have Shadows that are almost insensible; the parts farther removed, being, at the same time, shadowed by the Obscurity of the Walls, and receiving still more of this Shadow, as they are farther removed from the advanc'd Parts, and deeper involv'd in the Shade. Observe farther, that the Light, coming from on high, does not illuminate all Parts of the Face, but that some are skreened by the Relievo of others; as the Eye-brows keep the Light from the hollow of the Eye, the Nose from part of the Mouth, and the Chin from the Throat.