HOW WATER IS CHANGED TO VAPOR.

What happens when a kettle of water is put on a hot stove?

The water gets hot and boils away.

Where does it go? Is it destroyed?

The water is changed, but it is not destroyed. Coal burns, but we do not get rid of it altogether. It is changed into gas and smoke and ashes.

What is the water changed into?

It is changed to vapor. If we let the kettle remain on the fire long enough, the water it contains will all pass away as vapor.

Where does the vapor go? The water, though turned into vapor, must be somewhere.

It is floating about in the air of the room, though we cannot see it. The air holds the vapor, just as a sponge holds water.

Heat expands or swells air. Warm air, therefore, can contain more vapor than cold air. On a warm day there may be many times as much moisture in the air as on a cold day.

Moisten your slate with a damp sponge. Observe the disappearance of the moisture.

Dip your hand in water, and wave it in the air. The water on your hand disappears. Where has it gone?

When wet clothes are hung on the line, they soon become dry. What becomes of the water in the clothes?

If we set a plate of water out in the sunshine, what happens? Is the water lost?

The streets and roads were wet and muddy, now they are dry. What has become of the water? Has it all sunk into the ground?

Sometimes we see leaves and grass sparkle with water-drops, early in the morning, When the sun shines out and warms the air; what happens?

Why does vapor rise into the air?

Why does smoke go up? Because it is lighter than air. As vapor is lighter than air; what do you think ought to happen to it?

LESSON XV.

HOW VAPOR IS CHANGED TO WATER,

Heat, as you have learned, changes water into vapor. You must also know that cold turns vapor back into water again.

Now let us think of the kettle with the boiling water. You will notice a little space; quite close to the spout, where nothing can be seen. Is there no vapor there?

Yes, there is vapor there, but it cannot be seen; it is invisible. A little way from the spout we see something white, like smoke. This is only the vapor that has been chilled by the cool air and changed back again into water. The water is in the form of very fine particles, and may be called water-dust.

Hold a cold plate over boiling water. Observe how the water-dust gathers into drops that roll down the plate.

You have seen the inside of windows in cold weather covered with moisture. Where does it come from? Why did it form there? Why does it sometimes run down on the cold pane?

The vapor in our breath turns into water on frosty mornings. Explain this.

Carry a pitcher of ice-water into a room, and notice what takes place. A thin mist at once gathers on the outside of the pitcher. What takes place among the little drops of mist? What becomes of these larger drops?

Where does the water which collects on the outside of the pitcher come from? Does it come through the pitcher from the inside? Would the same thing have taken place if some other cold object had been used instead of a cold pitcher?

Write out what you have learned about vapor.

LESSON XVI.

DEW, CLOUDS, AND RAIN.

The sun is all the time heating the water on the land and in the sea, and changing it into vapor, which rises in the air. We cannot see the vapor; but it is in the air around us.

If the vapor in the air is suddenly cooled, a strange thing happens. Some of it quickly changes back into water. You have often seen, in the early morning, little drops of water hanging like pearls upon the blades of grass.

Now, where do these drops come from? They come from the air. The vapor in the air floats against the cold grass and leaves, and is cooled and changed into tiny drops of water. We call this dew.

Of what use is dew?

If the night is quite cold, the dew will freeze. It is then called frost. You have seen the frosty window pane with the beautiful pictures upon it.

Make a picture of the window as you remember it, covered with the pretty things made by the frost.

When vapor rises high in the cool air it is turned into very small drops of water or minute crystals of ice, and we can see it floating about in the air. It is then called a cloud. Almost any clear day you may see clouds form and then seem to melt away.

You have seen on a blue sky, light, fleecy feather-clouds. They are very high up, and it is very cold where they are. You have also noticed the clouds at sunset with their beautiful colors. As the sun sank lower and lower, how did they change, in shape and color?

When clouds are low down, near the earth, we call them fogs or mist.

If clouds are cooled, the little particles of water gather into large drops and fall as rain. If the drops should freeze in falling, we would call them hail.

What shape are the raindrops? Of what use is the rain?

Sometimes, when it is very cold, the moisture in the air freezes before it forms into drops, and falls in the beautiful flakes we call snow. Have you ever seen snowflakes through a microscope?

Snow keeps the roots of plants warm. Many plants would die in winter if it were not for the snow. What other uses has snow?

Observe the clouds; fog, rain, snow, dew, frost, and tell what you have noticed.

Write what you have seen or noticed about vapor, clouds, rain, etc.

LESSON XVII.

THE FAIRY ARTIST.

Oh, there is a little artist Who paints in the cold night hours Pictures for little children Of wondrous trees and flowers!

Pictures of snow-white mountains Touching the snow-white sky; Pictures of distant oceans Where pretty ships sail by.

Pictures of rushing rivers By fairy bridges spanned; Bits of beautiful landscape Copied from elfin land.

The moon is the lamp he paints by; His canvas the window pane; His brush is a frozen snowflake; Jack Frost the artist's name.

LESSON XVIII.

HOW RIVERS ARE MADE.

Have you ever seen a brook or creek? A river? Is there a brook or river near here? Who can tell where it begins? where the water conies from that fills it? where it goes? Let us try to understand this.

As vapor rises into high, cool air, or is carried with the air in winds up the sides of mountains, it turns into water again, and comes falling down as rain.

Now think where the rain that falls on mountains must go. Some of the water runs off on the surface, down the mountain slope. Some sinks into the ground, and runs along in little streams below the surface. It will appear again, bubbling out of the mountain side as a spring. The spring is the beginning of a river.

Did you ever see a spring? Where was it? Was it shaded by trees? Where did the water come from? Did you drink from it? Was the water pure and cold? Where did the water go after leaving the spring?

From the spring flows a tiny, thread-like stream, so small that we can easily step across it. This little stream is called a rill.

Other rills meet this, and form a larger stream, which is called a brook or creek.

As the brook flows on, it is joined by other streams, until, little by little, it becomes a wide and deep river on which large boats may float. At last, it finds its way into the ocean.

Where a river begins is its source. The place where it flows into another body of water is called its mouth. The land over which it flows is its bed.

A river has two banks. As we go toward its mouth, the right bank is on our right hand, and the left bank is on our left.

Do you live near a river? Where does the water come from? In what direction does it flow? Why does it flow in such direction? Does it wind about much? Does it flow into the ocean, or into another river?

Is the water fresh or salt? What grow on its banks? Near which bank do you live?

Make a picture of a spring, and a brook flowing from it. Draw the tall grass and plants that grow near it.

Write the names of all the rivers you have seen.

Write the following:

Water flowing out of the ground is called a spring.

From springs flow small streams called rills, brooks, or creeks.

A large stream of water flowing through the land is called a river.

A small stream of water flowing into a larger one is called a tributary.

The source of a river is where it begins. The place where it empties into another body of water is its mouth.

Every river has two banks--a right-hand bank and a left-hand bank.

LESSON XIX.

MORE ABOUT RIVERS.

Let us have another chat about the river. We may fancy that we are following it in its course to the sea. We shall then learn for ourselves many things we do not know about rivers.

We will begin our journey at its source. Here it is a little rill, formed by water that trickles from a spring, or by the melting of snow.

As it flows on, it is joined by many other little streams, until it grows to be much larger.

There is a large word used for a stream that feeds another stream. Do you know what it is? The word, is tributary. Tributaries are often called branches.

Before we leave this part of the river, I wish you to learn another hard word.

You have seen the water run off the roof of a shed. The ridge; or highest part of the roof, divides the rain that falls on it, so that part of the rain flows down the one side, and part of it flows down the other side.