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AGRICULTURE 



Nature of erosion. By erosion is meant the wearing 

 or carrying away of soil by the action of running water and 

 the wind. Erosion by running water takes place in some 

 degree on all slopes; the hills are gradually but constantly 

 being carried into the valleys. But it is on the steep hillsides 

 where the velocity of the water is greatest that most damage 

 is done. The reason for this is easily seen when it is re- 

 membered that the transporting power of water increases 



A hillside, showing the effects of water erosion. 



as the sixth power of its velocity. This means that doubling 

 its velocity increases the carrying power sixty-four times; 

 trebling its velocity increases the carrying power seven hun- 

 dred and twenty-nine times, and so on. 



The texture of the soil has much to do with erosion. 

 All soils that permit ready absorption of water, as from 

 rains or melting snow, leave less to run over the surface, 

 and so are less subject to erosion than dense clay soils. 



Effects of water erosion. Erosion by running water 



