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sufficient to account for the enormous European and American 

 deposits of boulder clay on any reasonable grounds. If icebergs 

 brought the stones from the Arctic Circle, they evinced a most 

 extraordinary reflective power, as they invariably deposited their 

 burden of rocks where counterparts could be obtained /// situ in 

 not distant localities. As the iceberg theory is thus untenable, we 

 are compelled to assume that the Boulder Clay deposits owe their 

 origin inore or less to land ice, which we must now examine. 



Undoubtedly there was a time, geologically speaking not long 

 ago, when a great portion of Europe was swathed in ice. Some 

 astronomical geologists think that such epochs occur in cycles, 

 and fancy that it may be possible to predict the period when our 

 beautiful Lake Country will once more be sealed with a coating of 

 ice, and when England will be as desolate as the interior of Green- 

 land is now. Happily this is placed so far in the future that we 

 need not personally make a trouble of the matter. We may 

 calmly examine the data of the past by the light of the little 

 knowledge we possess of what is now going on in the cold polar 

 latitudes. We are in a tolerably warm cycle now. The ice, 

 which enveloped a great portion of the British Islands, North 

 Germany, Switzerland, Italy, and perhaps France, has shrunk till 

 the glaciers of the highest mountains are alone left for our 

 examination, and to study it thoroughly we must go far away to 

 the northwards, where physical difficulties present insurmountable 

 obstacles to exhaustive investigations. The same circumstances 

 have taken place in the southern hemisphere. Great as are the 

 obstacles to examination in the north, they are as nothing when 

 compared with those which are encountered in the southern polar 

 regions. Beyond the facts that the cold is intense, that a conti- 

 nent is buried beneath ice, and that great ice barriers exist for 

 hundreds of miles, our knowledge is too vague and superficial to 

 warrant any scientific deductions being drawn, which could be 

 utilized in our present enquiry. Although more is known about 

 the Arctic Circle, yet it is but very little ; and for information as 

 to the action of land ice, perhaps Greenland is the country whence 

 we may best derive data suitable for our purpose. But our know- 



