'i ml linhn m ;/' Northern / 



Cretaoeoufl is deported uneonfonnahly upon these, ri.-in;: to the 

 .'it of hut a few hundred feet above the sea. North f tin- 

 California liiu', the n.cks forming the mountain-. a< 

 mentioned, arc almost entirely erupt i\e : and it ise\ident that 

 this has heeii the theatre ..f more violent \olcanic action tlian 

 any other part of the continent known to us. MOM of the erup- 

 tions took place in Tertia y tunes, as we know fr..m the inter- 

 calation of tin' trap overflows with the Tertiary lake->edmi< 

 many of which are store-houses of vegetable and animal fV 

 hut they have continued down to the present da\. 



Manv years ago. when connected with Western Coveniment 

 Surveys, I followed these mountains from the California line 

 to the Columbia, and at several points crossed lava stream- 

 which had tlowed down the cast Hank of the Cascades, and 

 were as t'roh and ragged as the modern lava streams of Yesir. 

 Not a particle of vegetation had attached itself to them, and it 

 rtain that not a hundred years have passed since some of 

 them were (lowing. 



AVIINI (ii..\<ii:i;s OF TIN. CASI M>I: MorxTAiWS, 



A- lias hecn stated, the Rocky Mountain.-, from New V 

 to British Columbia, abound in evidences of ancient ^laciation. 

 This is also true of the I'inta Mountains, the \Vasatch. tin 9 

 erra Nevada and the Cascade Mountain*. 



In the irroiip of five snowy peaks, called in ' 'he Three 



SiM nise onlv three are vi>ihle from the \\'illam 



ley miniature glaciers were found by our party in 1855 at the 

 heads of Me Ken /.!'> Fork, and of one of the tributaries of thftlta 

 Chutes ; and on Mt. h'ainier a do/i-n r more have been described, 

 K>me many miles in length. Hut all the glaciers and snow-fields 

 now existing on the Cascade Mountains ai'e uf jnifieant 



compared with those of the glacial period. Then every gorge 

 was filled with snow ami ice, the bi d more irregular 



miti were oovered with glaciers, and these descended sc\ 



thousand feet below the , .ne of perpetual snow. Now 



we find, over miles square, the rock-surfaces plan. 



red like a plowed field, ai, > injecting crc->' anio 



rock, rough and ragged as it was, is rounded over and \\orn into 



