Page:Maury's New Elements of Geography, 1907.djvu/17

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Besides being interesting, the sea is useful. It is a great highway. Ships are all the time carrying things across it, from one country to another. If we go into a grocer's store, we see spices for sale. They grew thousands of miles away, and were brought over the sea in ships.





A watershed. Its slopes carry water from the ridge or divide.

2. Divisions of the Sea.—The sea is one sheet of water. A ship can sail all over it. But different parts of it are called by different names. The largest parts or divisions of the sea are called oceans.

There are smaller divisions that are partly shut in by the land. These are called gulfs, bays, and seas. A portion of a bay so nearly enclosed by land that ships can be sheltered in it is called a harbor.

A generally narrow passage of water connecting two larger bodies of water is called a strait.

In some cases bays and straits are caused by the ocean's wearing away the coast. In other cases they are caused by the sinking of a strip of the land, so that the waters of the ocean flow over it.

Some straits are called channels. Wide straits are sometimes called sounds.

3. Water upon the Land.—Besides the water of the sea, there is a great deal of water upon the land. Most of it is fresh.



And yet it all comes out of the salt, salt sea. Let us try to understand this. When it rains or snows the sky is covered, we know, with clouds. Clouds are vapor. They are like the steam which comes out of a kettle or an engine.



The sun is all the time heating the sea and making vapor rise. That vapor forms the clouds. The winds drive the clouds from the sea over the land, and down they come as rain or snow. Put when the vapor rises from the salt water it leaves the salt behind. And so,