GLACIAL AND POST-GLACIAL HISTORY 637 



cutting of the Narrows outlet. It would therefore follow that a 

 large part of the 120-160- foot fall of water-level required in order 

 to permit the emergence of the barrier south of Fort Edward was due 

 to uplift, and the above remarks concerning the rate of the uplift and 

 of the ice retreat would apply. 



The correlation above assumed has the advantage of being in 

 accord with the facts which suggest the existence of a Higher Glacial 

 Lake George during the retreat of the ice from north of Glens Falls 

 to near Street Road, and the disadvantage of permitting the forma- 

 tion of wave-wrought terraces at Street Road and Crown Point in 

 Higher Glacial Lake Champlain in the approximate neighborhood 

 of the ice under conditions which are cited below as causes preventing 

 the formation of such terraces in the Hudson- Champlain water 

 body. 



Second assumption. — If the upper levels at Street Road and 

 Crown Point be correlated with levels above the barrier south of 

 Fort Edward, then the Street Road gravel plateau, the Crown Point 

 high-level deposits, and a part of the upper series of wave-wrought 

 terraces at these places were formed in the Hudson-Champlain water 

 body. The absence in northern Champlain of the upper levels in 

 the upper series of these wave-wrought terraces may be ascribed to 

 the presence of ice here while they were being formed in southern 

 Champlain. Under this assumption the demands made by the post- 

 Higher Glacial Lake Champlain uplift at Street Road and Crown 

 Point, will possibly permit the correlation (i) of the highest Street 

 Road terrace with the 389-foot Glens Falls level, and (2) certainly 

 with the 340-foot level. If the first correlation be correct, it is fatal to 

 the hypothetical Higher Glacial Lake George ; or if the Higher Glacial 

 Lake George be real and not hypothetical, then its existence is fatal 

 to the first correlation, and probably also to the correlation of the 340- 

 foot Glens Falls delta with the Street Road and Crown Point levels, 

 although it is barely possible that the latter correlation is permissible, 

 even though the Higher Glacial Lake George did exist. If some ter- 

 races of the upper series at Street Road and Crown Point be thus 

 assigned to the action of the Hudson-Champlain waters, then it fol- 

 lows that when Higher Glacial Lake Champlain was inaugurated 

 the ice was as far south as the delta of the Bouquet River, where the 



