The Child's Book of Nature / Three parts in one

by Worthington Hooker

I have told you how water is in motion whenever it can be. It runs whenever it can get a chance to do it; but it is in motion in another way, which I will now tell you about.

From what water goes up into the air.

You hang out a wet cloth to dry. When it is dry, what has become of the water that was in it? It has gone somewhere. Where has it gone? It has flown, like the birds, into the air; but it has gone so quietly that nobody has seen it go. The little fine particles of the water that I have told you about have mixed up with the air, and are blown about with it every where. And so, when you write, as the ink dries on the paper, the water in it flies off into the air, leaving the dark part of the ink behind.

There is a great deal of water that is going up into the air in this way all the time. It goes up from every thing that is wet. After a shower, the ground, the stones, the houses, the trees, and plants are all very wet, but in a little time they are dry again. Most of the water on them has gone up in the air, and is mingled up with it. It has mingled with it in such a way that you can not see it. The air is generally as clear with all this water in it as it is when it is perfectly dry. Even in a bright, clear day, there is a great deal of water mixed up with the air.

But water goes up into the air not merely from things that appear wet. You remember that, in Part First, I told you that water is all the time going out from the pores of the leaves. A great deal of water is furnished to the air in this way.

Experiment with the arm and a glass jar.

Then there is water going up from the skins of animals. Much water goes from your skin into the air constantly, even when you can not see that you are perspiring. You can prove this by putting your arm into a glass jar, and holding it there some time. The inside of the jar will become covered with the water that comes from the pores of the skin on your arm. This is like the experiment with leaves noticed on page 77 of Part First.

Water in the breath.

There is water, too, coming out from the lungs of animals and mixing with the air. It comes from their lungs just as it does from the leaves, which you know are the lungs of plants. You can see this if you breathe upon a cold window. The moisture or water that is breathed out with the air from the lungs gathers upon the glass. In the morning you often see the panes of the windows in your chamber very wet. All this water has come from your lungs as you have slept. In a very cold day the water in your breath freezes upon whatever is about your mouth. You see the water of the breath of a horse frozen on the hairs about his mouth.

So you see water is going up into the air all the time from the ground, the leaves, the animals, and indeed from every thing that is at all moist. It goes up also in great quantities from seas, rivers, lakes, etc. Water, then, is always moving. It runs and it flies. It flies up into the air, and comes down again in the rain to run in the streams. It is ever going its rounds, going up and coming down, and none of it ever stays long in one place. The only way in which it can be made to keep still is to shut it up. Let it be free, and it will soon be gone, either by running or flying.