the rain and snow are fresh. Some of the rain and snow is at once drained off by rivers; some sinks into the ground.
Where streams overflow mud is deposited which builds up a plain, as is seen in this view of the Connecticut river. Scientists call this a flood plain; others call it bottom land.
Fresh water that bubbles out of the ground is called a spring; and yet it is only rain that sank slowly into the ground and comes bubbling out again.
The water from springs may be seen flowing down the hillside and looking like a bright stream of silver. Many little streams unite to make a larger one called a brook, or a still larger one called a creek.
In a dry country, streams cut through their plateaus rapidly, leaving hills whose sides are straight up and down. This is the Green river in Colorado. Compare with Yadkin river.
Now suppose several brooks or creeks come together and make a stream larger yet, what will that be? We call it a river. The beginning of a river is called its source; the end of it is called its mouth. Now let us follow a river that begins among the mountains. Let us go from its source down to its mouth.
The first part of such a river is very rapid. The water dashes down the mountain side. Sometimes it leaps from rock to rock and makes waterfalls.
When it reaches the plateau, it is still very swift. Here, along the bank, we see mills for grinding corn or making cloth. They have wheels which the water turns as it passes on its way to the sea.
The mills need people to work in them, and so there is a village or a town built near by. Many cities have been built on the banks of rivers just because the swiftly running water then could be used to turn mill-wheels. On page 46 is a picture of a New England river and cotton mills built at its falls.
The Yadkin river, North Carolina. Streams cut through the plateau, leaving the Piedmont, or foot hills, as we see them here. In the second cut notice how the land has been cut by streams.
From the plateau, the river comes down to the coastal plain. Here the land has very little slope, and the river flows slowly and becomes so deep that steamboats run on it. At its mouth we find cities called seaports, where ships bring in goods from other countries to be exchanged for goods that come down the river on boats, or over the land on railroads.
Another work that rivers do for us is to drain the surplus water from the land and carry it back to the sea.
A river, the Savannah, flowing through the coastal plain. The seaport is Savannah, Ga. Notice the ships. This plain is made of mud cut away from the plateau, and brought dawn by the river.
Every brook and every creek is made up of water that falls near it, and rivers are made of the water poured into them by brooks and creeks. A river and all the streams that carry their water into it make a river system, and the land from which they drain the water is called
