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r. C. CHAMBERLIN 



really compact and transparent. It varies from translucency in 

 the more dense layers to nearly complete opacity in the more 

 porous layers. This is an expression of lack of solidity and 

 may be noted as specially instructive since the ice is here near 



Fig. 66. Entrance to a tunnel under the side of Bowdoin glacier, looking down- 

 stream. The shoulder of rock which caused the undercutting of the stream is par- 

 tially shown at the left. The peculiar arching of the beds is an interesting feature. 

 Photograph by Professor Wm. Libbey, Jr. 



the end of its career as a part of the glacier. As it was derived 

 from the main ice-cap it may possibly have had as long a glacial 

 history as often falls to such ice. 



The stratification and the basal loading of the ice exhibited 

 along the extended vertical face are much the same as in the 

 glaciers previously described, but differ somewhat in the fact 

 that the layers of ice are more warped and contorted, a result 

 doubtless of the greater inequalities of the glacier's bed. Very 

 notable dips of the glacial layers, both up stream and down 

 stream, were frequently observed and sometimes reached large 



