PRINCIPLES OF GEOLOGY. 17 



known rocks which compose the interior of the earth,) are profusely 

 scattered on its surface. 



It is impossible to account for the vast heaps of this gravel by sup- 

 posing that it might be laid in its present situation by any streams such as 

 now water the earth. For it occurs abundantly in places where streams do 

 not run, where, indeed, they never did run ; neither is it confined to such 

 narrow paths as serve for the passage of rivers, nor is it laid in such 

 forms, but it is casually and unequally spread over all the face of the 

 country. The blocks of stone which have been thus rolled from their 

 native sites, are, in some cases, of so vast a magnitude, and have been so 

 strangely carried, even a hundred miles or more, over hill and dale, that 

 in vain do we think to assign any other cause for the phenomena, than 

 a great body of water moving upon the earth. With regard to the force 

 of this water, various facts, which have fallen under my repeated exami- 

 nation, may give some idea. On Shap fells in Westmoreland, a reddish 

 granite is well known, and its blocks are at once recognised by large 

 interspersed crystals of felspar. Now, by the force of the great currents 

 of water, blocks of this granite have been scattered over a large tract of 

 country to the south, where masses, some tons in weight, rest on high 

 ground near Sedbergh ; and, when the Lancaster canal was made, such 

 were found of great size in deep cutting, near the town of Lancaster. 

 Eastward, this granite has been carried by other currents of the same 

 water, over the deep vale of Eden, and the lofty range of hills which 

 extend along the western border of Yorkshire and Durham, across Stain- 

 moor forest, down the vallies of Durham, and the northern dales of 

 Yorkshire, across the vale of York, and the hills of the eastern point 

 of the county, to Scarborough and Flamborough head, where it rests on 

 the summit of the cliff one hundred miles from its ancient situation. 

 This is one of many instances. The dispersion of sienitic rocks from 

 Carrock fell, Cumberland, of granite from Ravenglass, and of whinstone 

 from Teesdale, is not less remarkable. Such facts cannot be seen with- 

 out astonishment, nor contemplated without full conviction. As to the 

 height of this flood in our own country, the sides of Ingleborough, on 

 which rest fragments of rocks transported from Keswick ; the brow of 



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