It happens very seldom that the reflexes are of the same colour with the body from which they proceed, or with that upon which they meet. To exemplify this, let the convex body D F G E be of a yellow colour, and the body B C, which reflects its colour on it, blue; the part of the convex surface which is struck by that reflected light, will take a green tinge, being B C, acted on by the natural light of the air, or the sun.