236 IRVING B. CROSBY 



fore the northerly-southerly direction may be considered as normal 

 for a valley in the region between the mountains and the sea; and 

 the few cases of west to east courses are exceptional. 



The writer believes that the present route of the Androscoggin 

 through the mountains in the middle province is not the original 

 course of the drainage of the watershed above Gorham, and also 

 that the route of the river below Bethel is entirely postglacial, the 

 present stream occupying parts of several preglacial drainage sys- 

 tems. 



The ice sheet crossed this region in a southeasterly direction, 

 widening the valleys and passes, and developing the characteristic 

 U-profile. 



In the mountains till is widespread, but well-defined moraines 

 and drumlins are few. The valleys are relatively narrow, the 

 divides are generally high, and streams are principally controlled 

 by the bed-rock topography and not by glacial deposits. 



In the lower province, just east of Bethel, the valleys are 

 broader, the divides lower; and the streams are partly controlled 

 by glacial deposits, while nearer the coast moraines and drumlins 

 are common, rock hills are scarce, and stream control is largely by 

 surficial deposits. 



FORMER COURSE OF THE UPPER ANDROSCOGGIN 



The present divide between the drainage to Long Island Sound 

 and to the Gulf of Maine extends northerly from the Presidential 

 Range between the valleys of the Connecticut and Androscoggin 

 rivers. This divide has several low passes, one between Berlin 

 and Grove ton having a summit less than 100 feet above the Andros- 

 coggin River or i , 100 feet above sea-level. The mountains forming 

 the divide are composed of granitic rocks and are less high and 

 rugged than the schist mountains of the main ranges. The 

 irregular northerly-southerly trend of the divide, and its broken 

 character, contrast strongly with the Presidential, Carter-Moriah, 

 and Mahoosuc ranges, which have a regular northeast-southwest 

 trend and have only one low place, the valley of the Androscoggin 

 at Gorham. 



