Describe the landscape with wind and with water and with the setting and rising of the sun.

Wind.

All the leaves that hung toward the ground, in the bending of their little branches together with the branch turned over, straighten themselves with the course of the winds, and here their perspective performs the contrary office, for if the tree is between you and the birth of the wind, the tips of the leaves that are toward you make their natural showing, and the opposite leaves, which had to turn their tips in the contrary direction, are by their overturning turned with their tips toward you.

The trees of the fields stand out little one from another, because their illuminated parts border upon the illuminated ones behind them, and in these there is little difference between the lights and the shadows.

When the clouds interpose themselves between the sun and the eye, all the edges of their globes are bright and toward the middle they are dark. And this happens because, toward the upper said edges, they are seen by the sun higher than they and by you lower: and this same thing happens in the settings of the branches of plants, and again both clouds and trees become partly bright by being somewhat transparent, and at the edges more thinness shows.

But when the eye finds itself between the cloud and the sun, the cloud does the opposite of what it did before, because the edges of its globulences are dark and toward the middle they are bright. And this happens because you see that part which the sun also sees in the face, and because those edges have something of the transparent and render to the eye those parts that hide behind them, which, not being seen by the sun as the parts turned toward it, must needs be somewhat darker. Again it may be that you see the minutiae of those globulences from the underside, and the sun sees them from above, and because they are not situated so as to render the brightness of the sun as before, they are therefore dark.

The black clouds that are often seen above the bright ones lit by the sun are shadowed by the other clouds that interpose themselves between them and the sun.

Again the globosities of the clouds that have the sun in the face show their edges dark, because they stand against a bright field; and that this is true, look at the summit of the whole cloud, which is bright, because it stands against the blue of the air, which is darker than the cloud.

Describe a land and a sea wind. Describe a rain.

In the morning the mist is thicker toward the height than in its low part, because the sun draws it upward, whence in great buildings, although the top is as far from you as the foundation, that top will be unknown to you. And for this the sky shows itself darker toward the height and toward the horizon, and does not turn blue, but is all smoke and dust.

The air infused with mists is entirely deprived of blue; but it only appears of that color of the clouds that whiten, when the weather is serene; and the more you look toward the west, the darker you will find it, and more luminous and clear toward the east. And the greenery of the fields in a middling mist turns somewhat blue, but blackens in the thicker.

The buildings toward the west show only their luminous part, once the sun uncovers itself; the mists hide the rest.

When the sun rises and drives away the mists, the hills begin to clear on that side whence they depart, and become blue, and smoke toward the fleeing mists, and the buildings show lights and shadows, and in the less thick mists show only the lights, and in the thicker nothing; and this is when the motion of the mist departs crosswise, and then the edges of that mist will be little evident against the blue of the air, and toward the earth it will seem almost dust that rises.

The thicker the air, the rarer will appear the buildings of the cities and the trees of the fields, because only the most eminent and large will show themselves.

The mountains will be sparse, because only those show that have greater intervals, because in such spaces the thickness multiplies in such a way that it makes such brightness that the darkness of the hills divides and dispatches itself well toward its height; in small and near hills not so much interposes, and therefore they are less discerned, and less in their low parts.

The shadows tinge everything with their color, and the more a thing departs from those shadows, the more it renders itself of its true and natural color.

Half purification.