36 



Adventures in Scenery 



uplift has meant increased velocity in the streams and there- 

 fore greater eroding power. Every subsidence or depression 

 has meant stagnation of erosion and a tendency to deposition 

 of the materials eroded on higher lands. Thus vast mountain 

 ranges have been worn down and carried away, and deposits of 

 rock waste to almost unbelievable thicknesses laid down in 

 basins or depressions which may or may not have been filled 

 with water, may or may not have been bays or arms of the sea. 



Courtesy Los Angeles flood Control Commission 

 FIG. 1 1 . Mouth of Ly tie Canyon, about six miles north of Fontana. 



That a basin such as the Los Angeles basin shall have received 

 deposits of broken rock thousands of feet in depth is not more 

 difficult for the mind to grasp than that rock formations thou- 

 sands of feet in thickness, whole mountain ranges, have been 

 worn down and carried away. Through such changes has 

 California passed. Running water has been acting all the time. 

 Rivers have been "behaving" as rivers do during all the ages 

 from Jurassic time to the present. 



How does a river begin? What is a river any way? Is 

 there any difference between a river and a creek except in the 

 matter of size? May a creek grow to be a river? If rivers 



