Light is the chaser away of darkness. Shade is the obstruction of light. Primary light is that which falls on objects and causes light and shade. And derived lights are those portions of a body which are illuminated by the primary light. A primary shadow is that side of a body on which the light cannot fall.

To any white body receiving the light from the sun, or the air, the shadows will be of a bluish cast.

A single and distinct luminous body causes stronger relief in the objects than a diffused light; as may be seen by comparing one side of a landscape illuminated by the sun, and one overshadowed by clouds, and illuminated only by the diffused light of the atmosphere.

Vitality and beauty are gifts of Nature for those who live according to its laws.

Beauty perishes in life, but is immortal in art.

Darkness is absence of light. Shadow is diminution of light.