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as the ice melted, at or not far from the spot where the drift is 

 found to-day. In the notes that follow, I shall attempt to account 

 for many of these glacial phenomena by this, as it seems to me, 

 simpler method. 



First, in regard to the relationship between the forms of the 

 drift mounds and those of the underlying rock. We have first to 

 remember that when the ice of the major period of glaciation 

 ceased to move, and began to melt away on the spot, this ice was 

 charged throughout with mud and stones of all sizes. In places 

 the proportion of extraneous materials of this kind to the ice may 

 have been even as high as one to fifteen, or even, locally, and in 

 exceptional cases, as much as one to ten. We have also to 

 remember that one result of the prolonged rasping and grinding of 

 the rock surface was the formation of wide furrows ranging, in a 

 general way, with the direction of outcrop of the harder beds of 

 rock, but more or less modified by the predominating direction of 

 movement of the ice through its whole stay there. Now, when 

 the ice began to melt, the water resulting from its liquefaction 

 would naturally flow away towards the lower ground along any 

 lines of depression that might happen to traverse the rock surface 

 beneath the ice. As a consequence, as the ice melted, and the 

 stones and mud were liberated from any part of the ice, this 

 sediment would naturally tend to remain in greater quantities at 

 those points where it was out of reach of running water, than along 

 those lines where the water of liquefaction was working its way 

 seaward between the ice and the rock, as it was along the furrows. 

 Consequently, as the liberation of the sediment, mud, sand, gravel, 

 and boulders, proceeded, more and more of it accumulated over 

 the old pre-existing ridges, until in the end these became enwrapped 

 in layers one over the other, the form of each layer, in a general 

 way, being determined by the form of the surface beneath. I do 

 not for a moment suppose that as the ice melted it formed bridges 

 across the furrows extending from one mound to another. No one 

 who has learnt anything of the plastic nature of ice could suppose 

 that for a moment. On the contrary, I have very little doubt that 

 the ice was always in contact with the growing mound of drift, and 



