The air moves like a river and carries the clouds with it; just as running water carries all the things that float upon it.

A bird as it rises always sets its wings above the wind and without beating them, and it always moves in a circular movement.

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

The water wears away the mountains and fills up the valleys, and if it had the power it would reduce the earth to a perfect sphere.

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.

Although human ingenuity may devise various inventions which, by the help of various instruments, answer to one and the same purpose, yet will it never discover any inventions more beautiful, more simple or more practical than those of nature, because in her inventions there is nothing lacking and nothing superfluous; and she makes use of no counterpoise when she constructs the limbs of animals in such a way as to correspond to the motion of their bodies, but she puts into them the soul of the body.