THE "GREAT ICE AGE." 117 



Geikie, and may safely be accepted as incontrovertible. 

 Whence, then, the great difference ? 



One of the suggestions to which I have already alluded 

 as afforded by reading Mr. Geikie's book was a hypothetical 

 solution of this difficulty, but the verification of the hypo- 

 thesis demanded * re-visit to Norway. An opportunity for 

 this was afforded in the summer of 1874, during which I 

 traveled round the coast from Stavanger to the Arctic 

 frontier of Kussia, and through an interesting inland dis- 

 trict. The observations there made and strengthened by 

 subsequent reflections, have so far confirmed my original 

 speculative hypothesis that I now venture to state it briefly 

 as follows : 



That the period appropriately designated by Mr. Geikie 

 as the " Great Ice Age" includes at least two distinct pe- 

 riods or epochs the first of very great intensity or magni- 

 tude, during which the Arctic regions of our globe were as 

 completely glaciated as the Antarctic now are, and the 

 British islands and a large portion of Northern Europe 

 were glaciated as completely, and nearly in the same man- 

 ner, as Greenland is at the present time; that long after 

 this, and immediately preceding the present geological 

 epoch, there was a minor glacial period, when only the now 

 existing valleys, favorably shaped and situated for glacial 

 accumulations, were partially or wholly filled with ice. 

 There may have been many intermediate fluctuations of 

 climate and glaciation, and probably were such, but as 

 these do not affect my present argument they need not be 

 here considered. 



So far I agree with the general conclusions of Mr. Geikie 

 as I understand them, and with the generally received hy- 

 potheses, but in what follows I have ventured to diverge 

 materially. 



It appears to me that the existing Antarctic glaciers and 

 some of the glaciers of Greenland are essentially different 

 in their conformation from the present glaciers of the Alps, 

 and from those now occupying some of the f jelds and val- 

 leys of Norway; and that the glaciers of the earlier or 

 greater glacial epoch were similar to those now forming the 

 Antarctic barrier, while the glaciers of the later or minor 



