EVIDENCE AS TO LOCATION 181 



channel would necessarily be at a higher level near the Warrensburg end ; 

 (3) the decidedly unfavorable direction of the depression for ice erosion 

 and the existence of so much rotten rock even well down in the depres- 

 sion, both prove that this passage is now essentially as it was just before 

 the Ice Age, and this in turn means that it must have been the lowest 

 passageway across this highland belt; (4) the harmony of this channel 

 with the rock structures — as, for example, the strike of foliation of the 

 gneisses and the strike of a fault — which quite certainly has developed a 

 line of weakness through the ridge here; (5) the very direct course of 

 such a channel affording a natural outlet for the Hudson from the Adi- 

 rondack highlands, and (6) the perfect continuation of this channel 

 through a low and distinctly drift-filled depression just west of French 

 Mountain and south of the end of Lake George. 



Some of the considerations unfavorable to a Warrensburg-Hillview 

 channel are: (1) The higher elevation (nearly 900 feet) of the divide in 

 this depression; (2) the nearness of the present divide to Lake George; 

 (3) the more favorable direction of this depression for ice erosion, and 

 the fact that where exposed the rock is comparatively fresh go to show 

 that this depression was not so low just prior to the Ice Age; (4) the 

 lack of harmony with rock structures here ; ( 5 ) the more indirect course 

 of a channel through this depression, and (6) the probable continuation 

 of such a channel across what is now a shallow part (as shown by the 

 islands) of Lake George, and thence to the east side of French Mountain. 



Emphasis should be laid on the fact that the pre-Glacial course of the 

 Hudson, here accepted by the writer, was in perfect harmony with certain 

 major topographic and structural features. A normal fault of very con- 

 siderable displacement exists along the west side of Lake George towards 

 the south end, as proved by the fact that Paleozoic rock near the lake level 

 comes sharply against the pre-Cambrian of the highlands just to the west. 

 Due to the more rapid wearing down of the softer Paleozoics on the east 

 side of the fault during pre-Glacial time, a prominent depression was de- 

 veloped, which continued for some miles southward and to the west of 

 French Mountain. Thus the pre-Glacial Hudson followed rock structures 

 (foliation and fault) from Warrensburg to Lake George, and after cross- 

 ing the great fault continued southward in adjustment to rock structure 

 by following the fault depression (now deeply drift-filled) just west of 

 French Mountain and then emerged on the Paleozoic lowlands towards 

 Glens Falls. Thus, while the possibility of a pre-Glacial Hudson Elver 

 channel just east of French Mountain is admitted by the writer, the best 

 evidence is thought to be against it. 



The pre-Glacial Hudson was joined by the Schroon Eiver just east of 



