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University of California. 



[Vol. 1. 



elevation as the summit of the road on Cape Mendocino Ridge, 

 and the summit is again flat and plateau-like, though no gravels 

 were observed. Beyond Bear River Ridge the sides of the lower 

 portion of Eel River Valley are distinctly scored with stream ter- 

 races up to about 700 feet. 



This thousand-foot baselevel bench mark, which is so persist- 

 ent and so well defined, and other less prominent ones not here 

 referred to, are clearly merely notches in the front of a plateau of 

 much higher altitude. There are very distinct flat profiles at a gen- 

 eral altitude of about 1,600 feet, and above this there rise somewhat 

 higher low rounded profiles, and above this still and in contrast to 

 all below are the sharper peaks of residual mountains. This lan- 

 guage will, the writer fears, seem vague and indefinite, but in the 

 absence of topographic surveys other than that of the exceedingly 

 narrow strip given in the Coast Survey charts, it is difficult to be 

 more precise. Enough has, however, been said to show that here 

 in Humboldt County, where the broad peneplain effects of Mendo- 

 cino and Sonoma Counties are lacking, there is still abundant 

 evidence of very extensive uplift. A critical inspection of the topo- 

 graphic profiles, whose features are so difficult to express in words, 

 and which must be seen to be fully appreciated, convinced the 

 writer that they afford evidence of an uplift of from 1,600 to 1,700 

 feet, and there are strong suggestions that the full measure of the 

 uplift may be as much as 2,100 feet. 



Stream Topography. — The drainage features of the western 

 slopes of the northern Coast Ranges of California loudly invite the 

 attention of the devotees of the new science of geomorphology. 

 They promise a rich harvest of facts illustrative of the principles of 

 geomorphogeny to the student who will undertake their investiga- 

 tion. To see a problem in nature and to obtain some taste of the 

 pleasures of its pursuit is one thing. To investigate the problem in 

 all its richness of detail is another. The writer sadly confesses that 

 he has only seen the problem, not investigated it. Any conception, 

 therefore, of the stream topography which may be obtained from 

 these notes is but a glimpse of the general product of processes of 

 land sculpture, of whose detailed history, interactions, and adjust- 

 ments we have none of the precise knowledge which inductive 

 geomorphology now demands. 



