ON THE GLACIATION OF THE ARCTIC AND SUBARCTIC REGIONS VTSITED ]iY 

 THE UNITED STATES STEAMER CORWIN IN THE YEAR 1881. 



By John Mdir. 



The monuments of the glaciation of the regions about Bering Sea and the northern shores 

 of Siberia and Alaska are in general much broken and obscured, a condition of things due in the 

 main to the intensity of the action of the agents of destruction in these regions, together with the 

 perishable character of the rocks of which most of the monuments consist. Lofty headlands, once 

 covered with clear Glacial inscriptions, have been undermined and cast down in loose, draggled 

 taluses, while others, in a dim, ruinous condition, with most of their surface records effaced, are 

 rapidly giving way to the weather. The moraines, also, and the grooved, scratched, and polished 

 surfaces are much blurred and wasted, while glaciated areas of great extent are not open to obser- 

 vation at all, being covered by the shallow waters of Bering Sea and the Arctic Ocean, and buried 

 beneath sediments and coarse detritus which has been weathered from the higher grounds, or 

 deposited by the ice itself when it was being melted and withdrawn towards the close of the main 

 Glacial period. But amid this general waste and obscurity a few legible fragments, favorably 

 situated here and there, have escaped destruction — patches of polished and striated surfaces in a 

 fair state of preservation, with moraines of local glaciers that have not been exposed to the heavier 

 forms of water or avalanche action. And had these fading vestiges perished altogether yet would 

 not the observer be left without a sure guide, for there are other monuments of ice action in all 

 glaciated regions that are almost unalterable and indestructible, enduring for tens of thousands 

 of years after those simpler traces that we have been considering have vanished. These are the 

 material of moraines, though scattered, washed, crumbled, and reformed over and over again; and 

 the sculpture and configuration of the landscape in general, canons, valleys, mountains, ridges, 

 roches moutonnees, with forms and correlations specifically glacial. These, also, it is true, suffer 

 incessant waste, being constantly written upon by other agents; yet, because t he Glacial charac- 

 ters are formed on so colossal a scale of magnitude, they continue to stand out fr«e and clear 

 through every after inscription whether of the torrent, the avalanche, or universal eroding atmos- 

 phere; opening grand and comprehensive views of the ice itself, and the geographical and 

 topographical changes produced by its action in the form of local and distinct glaciers, (lowing 

 river-like, from the mountains to the sea, and as a broad, undulating mantle crawling over all 

 the landscape unhalting, unresting through unnumbered centuries; crushing and grinding and 

 spreading soil beds far and near to be warmed and fertilized by the sun, fashioning the features 

 of mountain and plain, extending the domain of the sea, separating continents, dotting new 

 coasts with islands, and fringing them with deep inreaching fiords, and impressing its peculiar 

 style of sculpture on all the regions over which it passes. 



A general exploration of the mountain ranges of the Pacific coast shows that there are about 

 sixty Ave small residual glaciers on the Sierra Nevada of California, between latitude 36° 30' and 

 39°, distributed singly or in small groups on the north sides of the highest peaks at an elevation 

 of about from 11,000 to 12,000 feet above the level of the sea, representatives of the grand glaciers 

 that ouce covered all the rauge. More than two thirds of these lie between latitude 37° and 38° 

 and form the highest sources of the Sau Joaquin, Tuolumne, Merced, and Owens Rivers. 



Mount Shasta, near the northern boundary of California, has a few shrinking glacier remnants 

 the largest about 3 miles in length. Northward, through Oregon and Washington Territory, 

 groups of active glaciers still exist on all the highest mountains — Mounts Jefferson, Adams, Saint 

 Helens, Hood, Rainier, Baker, and others; oue of the largest of the Rainier group desceuding 



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