TITLES AND ABSTRACTS OF PAPERS 81 



which would appear to phj^siographers to be natural mounds were built by 

 human hands. 



Presented in full extemporaneously. 



Discussion 



Mr. J. E. Todd : I would call attention in this connection to the fact that at 

 the 1877 session of the American Association for the Advancement of Science, 

 held in this city, a gentleman exhibited a model to show the similarity of the 

 largest Cahokia mound to the pyramid structures of Mexico and Yucatan. 

 At that meeting an excursion to the mounds was arranged. While on the trip 

 I personally heard Doctor Worthen, State Geologist of Illinois, who had studied 

 them, state his positive conviction that these mounds were not artificial but of 

 natural origin. 



Remarks were also made by Messrs. D. W. Ohern^ I. C. White, and 

 W. J. Sinclair. 



SALIENT FEATURES OF THE GEOLOQY OF THE CASCADES OF OREGON, WITH 

 SOME CORRELATIONS BETWEEN THE EAST COAST OF ASIA AND THE WEST 

 COAST OF AMERICA 



BY WARREN DU FUt SMITH 



i Abstract) 



The salient features of the stratigraphic succession in the Oregon Cascades, 

 so far as known, are reviewed in this paper. 



A survey of the literature and of the data gathered in recent field-work re- 

 veals the fact that not much is known with certainty about the formations 

 and events prior to the Tertiary. 



A second fact of importance, already known, is emphasized, namely, that 

 the later geological history of California and Oregon is very much the same. 

 This might appy to the State of Washington as well, but the writer has pur- 

 posely omitted a discussion of this, since he has never done any work there. 



The third fact of importance is the remarkable coincidences of geological 

 events on opposite sides of the Pacific, which can not be fortuitous. The two 

 most striking instances of these are the period of Tertiary gold deposition, 

 practically contemporaneous around the entire Pacific arc, and the tremendous 

 eruptions of basaltic and andesitic lavas which continue to this day, though 

 not on so extensive a scale as in the past, and which have caused the regions 

 bordering the Pacific to be designated as the "Circle of Fire." 



The general conclusion is that the geology of the various countries bordering 

 the Pacific must be deciphered and interpreted by duly considering the data 

 from all these regions, and that, geologically at least, the Far East has much 

 to contribute toward the solution of our Western problems and vice versa. 



Read by title in the absence of the autlioi'. 



