456 CHARLES EMERSON PEET 



WESTERN PASSAGE FROM HUDSON TO CHAMPLAIN VALLEY. 



North of Glens Falls (where the Hudson emerges from the Adi- 

 rondacks) the broad lowland occupied by the Hudson ends suddenly 

 in the rather abrupt rise of the land caused by the closing in of 

 the highlands from the east and from the west. Through this high- 

 land there are two narrow passages — one by way of Lake George, 

 and the other by way of Whitehall and southern Lake Champlain. 

 These two passages are separated by highlands reaching elevations 

 of more than 2,000 feet, and with a common elevation of 1,200-1,800 

 feet. This highland ends, however, in Mount Defiance near Fort 

 Ticonderoga, and north of this place the two passages unite and 

 broaden out into the wide valley between the Adirondacks on the 

 west and the Green Mountains on the east, in the bottom of which 

 is Lake Champlain. (See Fig. 18.) 



The Western or Lake George Passage is a long, steep-sided, 

 narrow valley opening out on a clay plain near Ticonderoga at the 

 north and connecting with the Lake Champlain valley. In the 

 bottom of this valley is Lake George, 32 miles long, and 2 miles wide in 

 its southern, and one-half as wide in its northern part. Its greatest 

 depth is no feet. At the south end of this valley there are two gaps, 

 the western one of which has a rock-bottom at more than 500 feet 

 A. T. The eastern and broader gap is blocked by a massive com- 

 plex gravel ridge, which is a northeastward continuation of the Glen 

 Lake kame area. (Fig. 18, No. 87.) Well data to the south of this 

 ridge indicate a filled valley with a bottom which is lower than the 

 deepest known part of Lake George. Through this massive gravel 

 ridge, which obstructs the south end of the Lake George valley and 

 is responsible for Lake George, there is a small gap followed by a 

 tributary of Glen Brook (the outlet of Glen Lake). This tributary 

 appears from the map to flow through a flat-bottomed valley, and 

 one of its branches starts from a low divide at 349 feet A. T. in this 

 valley, which separates it from streams flowing into Lake George. 

 As will be seen later, this flat-bottomed valley may have been the 

 outlet for a higher glacial Lake George, which existed (if it existed 

 at all) after the ice had retreated beyond the Glen Lake kames and 

 before it had retreated north of Ticonderoga. (See Fig. 18, No. 106.) 



