PHYSIOGRAPHIC GEOGRAPHY 



The Sierra Nevada Range terminates at the North 

 Fork of Feather River not far from the line of the 

 Western Pacific railroad. Its correlative, the Cas- 

 cade Range, has some common features in past 

 physiographic history, but in a hasty view it may 

 be sufficient to call attention to the greatest con- 

 trast, namely, that in the northern range upbuilding 

 by volcanic flows has played a vastly more import- 

 ant part than in the Sierra Nevada. At the extreme 

 southern end of the Cascade Range stands Lassen 

 Peak (Diller, 1895), an old volcanic cone which sud- 

 denly became active on May 30, 1914, and which 

 has now been in intermittent action of the explosive 

 type for nearly eight months (Holway, 1914). (See 

 PI. VI.) As this page was written, January 23, 1915, 

 the newspapers announced that at nine o'clock in 

 the morning the 74th eruption took place from a new 

 crater on the east side of the mountain.* Northward 

 the well known extinct (?) volcanic cones of Mount 

 Shasta, Crater Lake, Hood, and Rainier serve to 

 emphasize further the contrast between the Cascades 

 and the Sierra Nevada. 



The next of the four parallel physiographic belts 

 of the west coast region is the Pacific Valley Prov- 

 ince a depression, not continuous however, be- 

 tween the Cascade-Sierra Nevada Range and the 

 Coast Ranges. The valley of Puget Sound in the 

 State of Washington is continued southward through 

 the greater part of Oregon as the Willamette Valley, 

 and although the Cascade and Coast ranges for a 

 short distance practically meet in southern Oregon, 

 the same type of depression reappears beyond and 

 is known as the Great Vallev of California. As com- 

 monly described, the Pacific Valley Province ends 

 where the Sierra Nevada turns westward to meet the 

 Coast Ranges. The different portions of the Pacific 

 Valley are the lowland plains of the west coast in 

 which must always center the most important agri- 

 cultural interests. 



In the Pacific Valleys possibly the side trip avail- 

 able to the greatest number of visitors on the line 

 of approach to San Francisco may be made by 

 changing from the railroad at Sacramento, the 

 capitol of California, and continuing to San Fran- 

 cisco by steamboat on the Sacramento River and 

 through Suisun Bay and the northern half of San 

 Francisco Bay. The Sacramento River throughout 

 most of its course in the Great Valley has by floods 

 built up natural levees and these, strengthened by 



* The best railroad points from which to visit the peak 

 are Redding or Red Bluff on the west, or Susanville on the 

 east. An auto ride of fifty to sixty miles Is necessary to 

 reach the base of the mountain. 



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