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NEW YORK STATE MUSEUM 



presented itself, it might be expected that the ice would deploy 

 into it. Second. These local striae are due to a branch of the 

 main Chaniplain lobe which passed southward through the 

 mountain valleys on the west and rejoined the main lobe at Port 

 Henry. Third, the striae are due to a local glacier or to small 

 glaciers coining at least to within 60 feet of the present lake 

 level from snow fields in the high area on the west, whose culmi- 

 nating point. Mt Marcy, is L'4 miles distant in a wist by north 

 direction. 



The position and nature of the till deposits of morainai charac- 

 ter shown on the map are explicable by the second and third 

 hypotheses. The fact that the eastwest striae extend quite 

 down to present lake level favors the first hypothesis on 

 account of the difficult assumption that a local glacier would 

 push its front to so low a level after the main ice had 

 retreated from this latitude. On the other hand the striae 

 near the present lake shore come to the shore so abruptly 

 as to give no support to the first hypothesis. I was not 

 able to make out from the details of the few striae 

 observed whether the ice movement indicated by them was 

 toward or away from the present lake. In the case of the ledge 

 near the red schoolhouse southwest of Port Henry there are 

 crescentic flakes in the gneissoid rock with the horns pointing 

 to the northeast. I have seen similarly fractured pieces re- 

 moved in which the horns of the crescent pointed in the direction 

 in which the ice was moving. If that be true here it is a point in 

 favor of local glaciation. 



In the Mill brook locality, the glaciated ledge of the abnormal 

 set was overlain by a gravelly boulder clay containing fragments 

 of Potsdam sandstone, gneisses and limestones. 



Bulwagga mountain comes to the lake front with a bold es- 

 carpment and, blocklike, rises between the depressed region of 

 Port Henry and the similar area of Crown Point. In this latter 

 side valley glacial striae, n. 42° e., were observed just south of 

 the village on the north slope of Sugar hill. On the road from 

 Crown Point Centre to Coot hill, glacial striae may be seen 

 running n. 48° e. 



Yet farther south of the west side of the lake in the vicinity 

 of Ticonderoga, the striae range from n. 13° e. to n. 33° e., dis- 



