EDEN VALLEY AND YORKSHIRE -DALE DISTRICT. 99 



It has also been shown that much of the surface -configuration 

 that is characteristic of the Dale district has been due to glacial 

 erosion— and that, as a perfect gradation in form may be traced from 

 the straight lines of scar, which it seems impossible to refer to any- 

 other than glacial origin, to the crescentic scars that have all the 

 characteristics of cirques, these also have originated through glacial 

 erosion. 



In treating of the origin of drift, the principal conclusions are, 

 that the facts observed are irreconcilable with either the moraine- 

 profonde or the marine theory — and that the angular moraine-like 

 drift occasionally found in parts of the dales, the upper and lower 

 tills and the intercalated beds, the deposits of sand and gravel that 

 form the eskers, and, finally, the numerous boulders that are left at 

 nearly all elevations are each and all the results of the melting of a 

 great sheet of land ice that was charged throughout with rock- 

 fragments of all sizes and of all the kinds occurring within the area 

 wherein the ice originated. 



Lastly, the present unmodified form of the drumlins and eskers, 

 the entire absence of any thing like a terrace of marine origin, and 

 the difficulty of pointing to any case of boulder-dispersal in direc- 

 tions that glacial currents may not have taken — all seem to prove 

 that, whatever submergence followed the climax of the glacial 

 period, most of the existing glacial phenomena are the work only of 

 the ice sheet. So little, indeed, has the aspect of the country 

 changed in Postglacial times that in many places the larger rivers 

 are even now above the bases of the adjoining drift-mounds, whose 

 present form can hardly be referred to any other than glacial action; 

 and Postglacial denudation generally has effected so little that by far 

 the greater part of the present surface- configuration has, in one way 

 or another, resulted from the former presence of the great ice sheet. 



EXPLANATION OF PLATE II. 



Map to illustrate the Grlacial Phenomena of the Eden Valley and Yorkshire- 

 dale district. 



