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BOULDER CLAY. 



By Charlks Smith, M.R.I. A. F.G.S. 



(Read at Whitehaven. ) 



Until the past few years, the so-called Boulder Clay deposits 

 were comparatively little studied. More recently this early neglect 

 has been amply atoned. They might even be said to have been 

 too much studied, as many have worked upon them in order to 

 extract arguments in reference to subjects which are altogether 

 extraneous. The deposits are doubtless directly or indirectly of 

 glacial origin, these involve a " Glacial Epoch," and it has been 

 endeavoured on astronomical bases to calculate the time which 

 has elapsed since this ice period existed. Further, it has been 

 assumed that proofs of the existence of man may be found anterior 

 to the close of this epoch, and thus those, who have adopted 

 theories for or against the antiquity of man, have made the boulder 

 clay formation a battle ground for ethnological discussions. 



The first question for us to examine is, What is Boulder 

 Clay % Over a considerable portion of Northern Europe, as well 

 as in North America, we find that though the great slate, sandstone, 

 granite, or other formations appear on high ground, yet at lower 

 levels they do not form the absolute surface (irrespective of the 

 superficial beds of soil and disintegrated material) ; but between 

 the soil and the foundation rocks there occurs, in very varying 

 thicknesses of from a few feet to hundreds of feet, a peculiar clay, 

 in which a greater or less number of boulders are contained. The 

 clay is of different colours, but usually very tenacious and fine- 

 grained \ the stones may be of one kind only, or, as in our Furness 



