SOIL-FORMATION, WATER 



25 



Fig. 10. "Pot holes" formed in shale rock. The boulders ana pebbles 

 in the "pot" are set in motion by flowing water and thereby the rock is broken 

 down with the formation of soil material. 



velocity of a stream is doubled, its carrying power will 

 be increased sixty-four times. But the volume, and 

 therefore the weight, of a body varies as the cube of its 

 diameter. Therefore the diameter of the material 

 carried does not vary directly as the velocity of the 

 current, but at a less rate. 



This power of flowing water to carry rock material 



