64 The Willamette Sound. 



We started, it will be remembered, from 

 the capes with a theoretic elevation of the 

 waters two hundred feet above their present 

 level. The fall of the river, from the Lower 

 Cascades to the ocean, may be stated at forty 

 feet; the fall through the five miles of cas- 

 cades, at thirty-five feet. Above this there 

 are forty or fifty miles of narrow gorge 

 through a mountain range, with slopes too 

 steep for preserving old shore lines and 

 through which the river falls twenty feet more. 

 Here we find the first open space east of the 

 Cascade mountains, in which the waters of 

 that period if two hundred feet higher at 

 the capes than they now are would have had 

 an elevation above the present river level of 

 one hundred and five feet. There was at this 

 place a lake-like extension of the river seven 

 or eight miles wide and fifteen to twenty long, 

 and into this a semicircular system of streams, 

 six in number, brought a continued supply 

 of sediment -sand, clay and gravel and 

 buried, year after year, in the strata along the 

 margin of that lake, the record of the pass- 



