LAND WATERS STREAMS 



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fall, on the average, nearly half a mile in their flow. Their energy 

 is therefore great, and they are the great carriers of sediment from 



Fig. 68. Spokane River, 4 miles above Spokane, during flood. (Photo. 



by Tolman.) 



land to sea. The sediment which they carry is composed largely 

 of decayed rock, but undecayed rock is sometimes worn away, 

 especially where streams are very swift. 





Fig 69. Scene in the freight-yards of Kansas City after the flood of 1903. 

 (U. S. Weather Bureau.) 



Though the flow of some streams is so gentle that they do not 

 appear to work great changes in their valleys, others wear away 

 their banks so rapidly that the changes they produce may be seen 



