CHAPTER THREE 



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WATER 



Waters can be divided into two classes, big waters and 

 little waters. Big waters are the rivers, the lakes, and 

 finally, the reservoir of all water, the sea. Little waters are the 

 creeks and brooks, the water that flows under the ground, the 

 streams that fill roadside ditches and rush down the hillsides 

 after rains, the spring freshets that come with the melting snow. 

 Little waters make big waters, and big waters make the sea. 

 Until recently we have paid most attention to big waters and 

 have neglected little waters. Now we are beginning to see 

 that little waters are also important. 



THE HYDROLOGIC CYCLE 



To understand water you must begin at the beginning. This 

 is the hydrologic cycle. The hydrologic cycle is simply a kind 

 of map of the course of a drop of ra?n water from the clouds, 

 through the rivers, to the sea, and back to the clouds again. 



First, water falls from the clouds. This is precipitation. 

 It may come as rain, dew, snow, or fog. When it strikes the 

 land, some water is usually soaked in by the soil. This is infil- 

 tration. When the surface of the soil becomes saturated, the 

 water sinks lower to the sub-soil of gravel or porous rock. 

 This is percolation. The water has filtered through to the 

 sub'soil where it is now stored as ground water. Ground water 

 is the underground reservoir upon which over half of the 

 people in the United States depend for their fresh water sup 

 ply. 1 The surface of this reservoir is called the water table. 



1 National Resources Board Report, op. cit., p. 307. 



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