KINDS OF EROSION 175 



KINDS OF EROSION. 

 Erosion may be considered in four aspects — gully erosion, 

 sheet erosion, landslides, and river-bottom erosion. Hillside 

 erosion is sometimes included as a distinct type, but such ero- 



FiG. ss- — A WAGON ROAD ALONG A STREAM UNDERMINED DURING A 

 TORRENTIAL FLOOD. 

 On account of the poor plant cover there is an erratic run-off of fallen rain after nearly every rain 

 storm. The stream beds at the foot of the mountain, where the force of the water is greatest, 

 are gullied out, and the banks cave in. Most of the loosened silt and rocks is deposited in 

 the valley by subsequent storms. 



sion is usually either a form of sheet erosion or of gullying, or a 

 combination of both. 



