686 B. K. EMERSON CIRQUES AND TERRACES OP MOUNT TOBY. ' 



These scarps can not have been formed by water or ice moving parallel 

 to the direction of the valle}-, since they are lacking on the opposite west- 

 ern side of the valley as well as on both sides of the next valley to the 

 east. They are also marked by reentrant angles and projecting bastions, 

 as if the great blocks had been quarried ont, and there is no talus of such 

 blocks at the foot of the bluffs. Moreover, the bottom of each scarp 

 is not carried along at a constant level, as if controlled by a shore line, 

 but rises and sinks, or branches, often plainly controlled by the eastward 

 dip of the rock combined with the direction of the mountain side. 



We must, I think, come back to the opinion that the sheltered position 

 of the mountain behind the Deerfield range may have caused the late 

 advent and peculiar action of the main ice on the mountain, and have 

 been largely responsible for its peculiar position and shape, and especially 

 that it so directed the attack of the ice as to cause the formation of the 

 terraces. Whether it held back the ice so that small glaciers cut out the 

 cirques, as I have thought, or whether they were made by slow headward 

 wear of surface waters, combined with faulting, may be left undeter- 

 mined. 



