174 G. F. Wright — Continuity of the Glacial Period. 



to B. Between A and B the lower prong is entirely free from 

 foreign gravel for a distance of half a mile or more ; but the 

 valley of the prong through this distance is broad at the top 

 and V-shaped, and is distinctly constricted near B by the 

 gravel deposits. This portion of the valley could not have 

 been hollowed out of a gravel deposit such as exists upon the 

 northern prong, and nothing of the sort exists on the north 

 side. 



Figure 5. 



