Chapter 2

If we were really in a desert, we might see a company of merchants carrying goods to sell in the countries they visit. Such a company is called a _caravan_. The goods are packed in bundles, which are carried on camels' backs. The camel can live for a long time without drinking, and can carry a heavy load of merchandise a long distance. It is sometimes called the ship of the desert.

Why do travelers use camels to cross the desert? Why do they not use horses? If you can not find answers to these questions in your books at home, ask your teacher about them.

You have seen a small whirlwind in the street. The leaves flew round and round, the dust whirled along in clouds. Trees are sometimes torn from the ground, and houses overturned, by a strong wind.

Now think of a wind-storm in the desert. A loud, rustling noise is heard. Great clouds of fine sand are lifted into the air--clouds which darken the sun! Travelers must at once jump from their camels, cover themselves with their cloaks, and lie flat on the ground.

The poor beasts will close their eyes and nostrils, and kneel with their backs to the wind until the storm has passed over.

Thankful will the travelers be if none of them are buried in the sand.

LESSON XII.

HILLS, MOUNTAINS, VALLEYS.

The land is not always level like a plain. In some places it is high and uneven. We all know what a _hill_ is. It is land a little higher than the surrounding country.

Is there a hill near where you live? Let us walk to the _top_, and stand on its _summit_. We will start from the _foot_ or _base_ of the hill. Now we have climbed its steep, rough _sides_ or _slopes_. Was the ascent difficult? Is the view from the top fine?

What can you see from the top of the hill--meadow, river, lake, town? What grow on the hill? What live on the hill?

Which part of a hill is called the base, or foot? The slope, or sides? The top, or summit?

Give two names for the lowest part of a hill. Two for the highest part. Two for the part between the highest and lowest parts.

Parts of the land very much higher than the surrounding country are called _mountains_. Mountains are much higher than hills. Have you ever seen a steeple one hundred feet high? A mountain is as high as twenty such steeples, one on the top of the other. How high the mountains must be!

Some mountains reach away above the clouds. Their white tops seem to touch the sky. A man on the summit of one saw the clouds beneath his feet, while the sun shone where he stood. When it lightened he saw the flash far below him.

Is it warm or cold at the tops of mountains? With what are many high mountains covered, even in summer?

The land between mountains or hills is called a _valley_. Is there a valley near here? What do you call the ground on either side?

Would you like best to live on the mountains or in the valley? Why?

Are mountains of any use?

Yes, hills and mountains are of very great use. They make the earth more beautiful. Tops of high mountains are so cold that they turn the clouds into drops of water which fall as rain or snow. Then mountains give rise to rivers which make the valleys beautiful with grass and flowers. Mountains do much good to some countries by keeping off cold winds. They also give us coal and iron and other minerals which we find so useful.

Here is a picture. What do you call the very high land on the right and on the left? The long, narrow piece of land between the two mountains?

When you look at this picture you must think of a real valley between mountains.

Bring pictures of hills and mountains to school; if you can find them.

If you had a molding-board and a few quarts of sand; you might represent hills and mountains with valleys between. Think of a real hill while you mold.

Draw on your slate a hill you have seen with a little of the surrounding country.

_Write:_

A long, narrow piece of land between hills and mountains is called a valley.

A hill is land a little higher than the country about it.

A mountain is land that rises to a very great height above the country about it.

LESSON XIII.

RAIN, WIND, AND SNOW.

Do you see the dropping rain, Pitter-patter on the pane? How it runs along the street! And it wets our little feet; But it makes the green grass grow, And the tiny streamlets flow.

Listen to the wintry blast Moaning, shrieking, howling past, Striking with tremendous force Rocks and forests in its course; But it blows the windmills strong, And it sends big ships along.

Watch the pretty snowflakes fall, Some are large and some are small; Look, they cover all the ground, Miles of dazzling white around; But this covering, I am told, Keeps the earth from frost and cold.

Ah! and I must work alway, Life's not meant to spend in play; Every moment's fleeting fast, And our day will soon be past; If our work is truly done, It will last though ages run.

Of what use is rain? Of what use is snow? Of what use is wind?

LESSON XIV.

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.

Now, hills, like the roof of a house, send off streams on both sides. When it rains, or the snow melts, some of the water goes down on one side, some on the other. And that is why the hills which divide or part the waters of streams are called a _water-parting_ or _water-shed_.

Let us now go further down the stream.

Here we see it rushing rapidly down a steep slope. Its waters foam and dash between the great rocks that lie in the stream. Such places in the river are called _rapids_. Can you tell why they are so called?

The stream flows on. It has now reached a high ledge of rock. Over this it leaps, making a great foam and noise.

When the water of a river falls over high rocks, it is called a waterfall or _cataract_.

You may have seen the Falls of Niagara, the greatest waterfall in the world.

The course of our river is now through a lower country. The valley in which it flows spreads out, and the stream grows wider and wider. The water moves slower and slower.

Why is the river swift in some places, and in others slow?

At length it flows through an almost level country. It is here widest and deepest. Its course is more winding.

Do you know why it is crooked and winding?

Because on the steep hillside the water runs very rapidly, and is not easily turned aside. Where the ground is nearly level, it runs slowly, and is easily turned from its course.

LESSON XX.

THE BROOK.

From a fountain In a mountain, Drops of water ran Trickling through the grasses; So our brook began.

Slow it started; Soon it darted, Cool and clear and free, Rippling over pebbles, Hurrying to the sea.

Children straying Came a-playing On its pretty banks; Glad, our little brooklet Sparkled up its thanks.

Blossoms floating, Mimic boating, Fishes darting past, Swift, and strong, and happy, Widening very fast.

Bubbling, singing, Rushing, ringing, Flecked with shade and sun. Soon our pretty brooklet To the sea has run.

LESSON XXI.

WORK OF FLOWING RIVERS.

Would you like to know more about brooks and rivers--about the work they do?

Notice what happens when it rains. Little tiny streams are formed, which chase each other down the slopes. See how they cut away the loose soil and carry it off. Notice how muddy this loose soil makes the water. What becomes of this loose soil, or mud?

Fill a jar with water. Put in a handful of mud from the nearest stream. Shake the jar, and the water is muddy. Let it stand awhile. What do you notice? The water is clear, and the soil has settled to the bottom.

Follow the streams to the valley where they unite to form a river. When does the load of mud it carries settle? Here, where the water scarcely moves, we find some of the soil spread out over the ground near the river banks.

You have seen a river overflow its banks. When the water went down, it left a layer of rich mud, which made the soil very fertile.

Have you never seen the low ground on the banks of rivers covered with rich grass and clover?

Well, these fertile meadows were formed out of the loam that has been washed down the streams from the far-off hills and mountains.

Look at the jar again. Which settled first, the coarse material or fine loam? What kind of a deposit will be made in the upper course of a river? What kind toward the mouth?

High up in the valley, when the river is low, we see _pebbles_ in its bed; lower down, the pebbles are worn into _gravel;_ and as we get still farther down, we find the gravel ground into _sand_.

Examine the stones found along the shore of a brook or river. Some are quite smooth and round. They were not always so, but had sharp edges. Do you know what made them round?

When there are heavy rains, the rushing water sweeps large stones down the mountain side and into the valley. As they are carried down the stream, the stones, by rubbing against each other, are smoothed and rounded and ground into pebbles. The pebbles themselves are ground at last into gravel and fine sand.

This is what the streams are doing everywhere--plowing deep furrows in the sides of the mountains, grinding the pebbles and sand into fine soil, and carrying it into the valleys below.

LESSON XXII.

WATERDROP'S STORY.

Patter, patter, fall the raindrops on the brown leaves in the woods. Mr. Squirrel's bright eyes sparkle as he peeps out of his queer little home, a hole in the tree; his store of nuts has been carefully hidden away.

Splash comes a drop on a leaf just opposite him. Such a friendly little drop it is, for soon it tells this little woodland dweller of all its travels.

Let us listen, for we may hear too:

"My home," began the Waterdrop, "is in the wide blue sea, where I live with many, many other drops.

"One day as we rode up and down on the big waves, the sun shone down on us, and we grew warmer. Each little drop felt, 'Oh, if I could only get away from the other drops, how much cooler I should be!' Then each tiny drop separated from the others, and grew so small you could not see it.

"We, of course, grew lighter, lighter than the air. Up, up we rose into the bright blue sky. When we got pretty high, where the air was cool, we came closer together again and formed a great fleecy white _cloud_, that cast its shadow over everything. Then a friendly wind carried us along, and soon we left the sea behind. Far below; we could see green fields and waving woods."

"You must have been very happy" said the little squirrel.

"Yes; it was a merry life we led, as we floated hither and thither, playing with the sun-beams," replied the Waterdrop.

"But we came at last to a purple mountain, and a chill wind began to blow. How we shivered with the cold! Then we huddled close together to get warm. We were now heavy again--so heavy that we could not stay up in the air.

"Then,

'I'm going down to cheer a flower,' Cried a little drop of rain; 'I hear it sigh. It droops its head As if in weary pain.'

'And I will go!' 'And I!' 'And I!' Cried all the raindrops near. So down we went in merry haste The whole wide field to cheer.

"The drooping flowers lifted their bright faces to thank the little drops for the cool drink. Even the great tall trees nodded their heads in welcome."

"The grass on the hillside and in the valley must have been grateful, too, for your coming," said the squirrel. "It always looks so fresh and green after a shower. But, tell me, what became of _you_?"

"I fell where the ground was brown and bare, stopped for a moment, then went down, down into the ground, where all was dark. I met other drops trying to get out, and we went on together, turning first this way, then that way, till we burst into the sunshine again."

"We rested for a moment in a tiny pool of clear water; then I ran with the rest down the mountain side, slipping over smooth pebbles, and tumbling over sharp rocks, until I found myself in a deep, swift stream, where plants and trees grew on either bank."

"Soon we were in a broad, quiet river, flowing past the grassy hills and green pastures. Then we came to a big mill-wheel, upon which we jumped, and by our weight made it turn over and over, and thus move the machinery in the mill. Here we were tossed in the air, whirled around, and at last flung back into the river, where we sailed slowly and quietly as before.

"By and by, we saw large boats floating on the water. We passed towns and cities with busy streets and many people; and as our river widened, and we heard the big sea waves dashing against the shore, we knew our brothers and sisters were singing a welcome home.

"And now farewell, little squirrel. My story is done, and I must hasten to my home in the sea. Perhaps we shall meet again some day. I may float down to you, a white-winged snowflake, or patter down as I came this time, a tiny raindrop."

_Write the following:_

The water rises from the sea in vapor.

The vapor is turned into clouds, which fall in rain or snow.

The rain forms rivers, which flow back again into the sea.

Thus the water is always going round and round in its long and curious journey--up to the clouds in vapor, down in rain, back in streams to the place it started from.

LESSON XXIII.

THE RIVER.

"Oh, tell me, pretty river, Whence do thy waters flow? And whither art thou roaming, So smoothly and so slow?"

"My birthplace was the mountain, My nurse the April showers; My cradle was a fountain, O'er-curtained by wild flowers.