The ocean is the home of the water. The water would always remain in the ocean if it could, but the sun and air are continually at work stealing little particles away and sending them on long journeys.

The water particles are so small as they rise from the ocean that we cannot see them. By and by they crowd together and make the clouds that float across the sky. As soon as the clouds meet colder air, the little water particles rush together and thus become larger and larger until they grow so heavy that they can no longer float in the air, but must fall. Some of them fall into the ocean again, but others drop upon the land.

The raindrops that reach the land have many sorts of stories to tell before they again get back to the ocean. Some of them are at once snatched up again and are started upon another journey. The thirsty air, whether over the ocean or over the land, is ever in search of water particles.

If the air is very cold, the clouds turn to snow instead of rain. The feathery flakes fall slowly through the air and form a soft white mantle over the earth. Those that fall on lofty mountains form great banks which may not entirely melt and turn to water until late in the summer.

The raindrops that fall where the slopes are steep, where Nature has grown little vegetation, or where men have destroyed the earth cover, have little to detain them and are soon on their way back to their home. In their hasty journey they do much damage to the unprotected soil.

If the drops fall upon gentle slopes, or where there are marshes and lakes, or upon the forest with its decaying vegetation, or upon deep beds of gravel and sand, they are a long time getting back to the ocean.

We can in no way change the amount of rain that falls upon any part of the earth. We cannot call up a storm when we wish it, nor can we send it away when there has been rain enough. But there are many ways in which we can hasten or delay the return of the water to the ocean. Nature shows us some of these. The spongelike carpet underneath the forest holds the water until it has had time to soak into the earth from which it later emerges as springs. Nature forms basins on the heads of the rivers where a part of the water, instead of immediately flowing away, collects in the form of lakes. From these lakes the water runs away slowly instead of in torrential floods.

Only a few places in our country have more rain than is really needed. One of these is the region about the mouth of the Mississippi River upon the Gulf of Mexico. Another is upon the Northwest coast. Throughout the central part of the country the summer rains are sometimes too light to afford a full harvest. The rainfall upon the plains and valleys of the Southwest is so small that the only plants that can live there are those strange and curious forms that have become used to desert conditions. The only way in which these lands can be made useful to the farmer is by means of irrigation. To obtain water for irrigation we have either to go to the distant mountains and build reservoirs to collect the rains which fall there and then dig canals to carry the water to the desert valleys, or to make use of some river flowing through them, if they are fortunate enough to have such a river. Can you think of any rivers that are used in this way?

Although water sometimes seems the greatest blessing that we have, yet it may prove a curse if it is not looked after. If you give the water a chance to make gullies in your fields, you lose not only the water but the best of the soil also. If you cultivate your fields with care, most of the water will soak into the ground. If you are a wise farmer you know also that cultivation of the soil helps to hold the water, for it cannot escape through loose soil as it can through compact soil. Thus if you know how to handle both the water and the soil, you can, with only a little rain, accomplish a great deal.

We can, then, hold or conserve the water, first, by leaving the steeper slopes covered with vegetation; second, by keeping the soil loose; and, third, by building reservoirs to hold the floods. We can make use of the conserved water by carrying it in pipes or ditches to those regions where it is needed. We can get rid of too much water by draining the swamps, and building dikes to protect lowlands from river floods.

Let us now learn something of the different uses of water. Every one of our homes has its water supply. In the city the water comes through pipes from some distant reservoir. In the country the homes are so far apart that it is difficult to supply them in this way. The water in the streams is often not suitable for drinking, and if there are no springs near by it has to be obtained by some other means. Nearly everywhere in the earth under our feet water can be found by digging or boring a well. Sometimes we have to go only a few feet, at other times many hundreds of feet. This water in the earth, or ground water, is of very great importance. It enables us to build our homes where we wish. Spring water is that which finds its way to the surface through some tiny crack or fissure in the rocks. How delicious is the pure, cold water that comes out of the shady hollow in the hills! You can form in your minds a picture of the rain falling on some distant mountain, of its soaking into the ground and finally reaching the little crevices in the rocks. Along these crevices it may have crept for days and perhaps years until at last it found an outlet in some spring.

The great river flows by so quietly that we often forget in how many ways it is serving us. It serves not only those upon its banks but those who live hundreds of miles away and who, perhaps, have never seen it. It was the first and easiest means of travel used by our forefathers before there were any roads or railroads through the wilderness. It now aids in carrying on trade between different regions. If large and deep enough, it permits boats from all parts of the world to reach the very heart of our country.

Canals might be called artificial rivers. They serve an important purpose in nearly level countries where Nature has placed no navigable river. Although canal boats usually move slowly, yet they can carry goods cheaper than railroads can. The Erie Canal, in connection with the Great Lakes and the Hudson River, makes it possible for us to go all the way by water from the heart of the continent to New York City. The Erie Canal has helped make New York City the greatest city in our country. The canal across the Isthmus of Panama saves ships a journey of many thousand miles around South America.

Rivers serve us in yet another way by affording water for irrigation. A great river like the Colorado flows through regions of many different climates. Some rivers become so small in the summer that it is necessary to build great reservoirs at their headwaters in order to insure a supply when the crops need it. But in the case of the Colorado this is not necessary. The headwaters of this river are among lofty mountains, where the melting snows and summer showers make the waters of the river higher in the early summer than at any other season of the year. Thus its great delta, the Colorado Desert, has become the home of many thousands of people.

Another use which we make of rivers is by putting the water to turning mill wheels. If you will turn to your geographies, you will find that nearly all the great manufacturing cities of our country have grown up around rapids or waterfalls, where some river tumbles over a ledge of rocks.

Once we had to build our mills close to the rivers to use the water power, but this is no longer necessary. Now we build electric-power plants by the rivers and carry electric energy more than a hundred miles to any place where we wish to use it. Electricity made from the distant mountain waterfall will do any kind of work for us wherever we carry it. Thus we see that the river works for us in more than one way. After it has created power for our factories, it can be turned on to the thirsty fields, where it will serve us equally well.