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immense blocks from mountains too precipitous to allow of the 

 accumulation of snow or ice, and these would travel down the 

 glacial valleys in the form of moraines ; but the quantity must be 

 relatively small, and the question may be raised whether stones 

 can travel any distance along glaciers and escape falling into the 

 crevasses. There is also great waste along the sea-cliffs, as is seen 

 in the so-called "ice-foot," or masses of ice, perhaps, partially, 

 frozen sea water, which adhere to the lo'wer margin of the cliffs 

 and become laden with stones, broken off from above by the 

 action of frost. But these losses of the land are comparatively of 

 little account, and we may conclude that a country such as Green- 

 land, completely clothed in ice, must be suffering far less from 

 atmospheric action than any land, even in the most favoured 

 climes, which is exposed altogether. There is then to be con- 

 sidered the scraping action of the ice sheet, which must be 

 enormous to a degree beyond our comprehension in the earlier 

 portion of a glacial epoch. We may suppose that where this 

 action is long continued, the denudation must very materially 

 decrease, when once all the asperities have been worn off, and the 

 work of the ice is confined to grinding the rounded surface of the 

 subjacent rock. 



We have now arrived at another stage in our enquiry. In 

 what form is the material carried away by the ice, and in what 

 manner is the transit effected? We will first consider the stones 

 that fall down crevasses. What becomes of these? It has been 

 suggested that stones which from this cause become embedded in 

 the ice, gradually rise in the glacier and appear once more at the 

 surface. This seems a very hazardous conjecture, and if it were 

 true, the surface of glaciers should be pitted over with stones just 

 emerging into daylight from the bosom of the ice. We know that 

 such is not the case. Neither can the stones retain a horizontal 

 position, as the ice at the end of glaciers is free from impurities, 

 whether stones or dirt. But the vast heaps of moraine matter 

 which fall down crevasses must go somewhere ; and if the rocks 

 neither rise again, nor remain horizontal, they must sink to the 

 bottom, either to be ground into an impalpable powder, or to form 



