270 J. W. GOLDTHWAIT GLACIATION IN THE WHITE MOUNTAINS 



locally after the conditions on the surrounding lowlands had become 

 nearly normal. In his paper he alludes to Agassiz's belief that the 

 erratics on the moraine came from the south, and quotes Hitchcock on 

 the transportation of large boulders of coarse gray granite 4 miles down 

 the x\mmonoosuc Valley, in a westward course, to the Twin Mountain 

 House — an observation which will presently be discussed. He adds 

 nothing new, however, in the form of lithological evidence, to show that 

 there was a northward dispersion of drift toward the Bethlehem moraine. 

 After reporting that the moraine runs continuously from near the Twin 

 Mountain House past Bethlehem to Littleton — not less than 12 miles — 

 Upham proposes to correlate this Bethlehem moraine with patches of 

 similar topography and structure described by Agassiz near Center Har- 

 bor (south of the White Mountains) and by Stone in the Androscoggin 

 Valley (east of them), all lying, according to his hypothesis, on a 

 moraine which completely encircles the White Mountains. In view of 

 the fact that such a moraine would have a length of 100 to 150 miles, 

 and that of this a mere scrap, 12 miles long, has been seen to possess 

 continuity, and two other smaller scraps are reported, in a region where 

 kames, eskers, and boulder-strewn drift deposits are familiar features, the 

 correlation can not be recognized as other than a working hypothesis, to 

 prove which it would be necessary to carry on field studies around the 

 greater part of the circle. Without more definite proof of a transporta- 

 tion of erratics radially outward and downward from the White Moun- 

 tains, one is justified in assigning at least equal value to the hypothesis 

 that the Bethlehem moraine, as well as those east and south of the White 

 Mountains, was built at the southern border of the Canadian ice-sbeet 

 while it retired from the district, leaving the White Mountains compara- 

 tively free from ice. 



The field-work around Mount Washington in 1912 had led me to look 

 with disfavor on Doctor Upham's hypothesis. Had a local ice-cap been 

 left on the White Mountains, as he supposed, it would in time have given 

 place to radiating valley glaciers, and the records of these glaciers ought 

 to be discoverable in the form of moraines in the valleys draining the 

 central range. The lack of morainic deposits at the lower ends of the 

 White Mountain ravines seemed to indicate that the cirque-cutting 

 glaciers operated before the last regional glaciation, and were not re- 

 . established by local snowfall in the closing stage of the glacial period. I 

 was therefore not surprised to find evidence which seems to indicate that 

 the Bethlehem moraine was built at the southern margin of the Canadian 

 ice-sheet rather than at the northern margin of a White Mountain ice-cap. 



Our study of the Bethlehem district included an examination of its 



