NORTH AMERICA IN THE ICE PERIOD. 231 



Scandinavia. The more eastern lines penetrate the edges of Russia 

 and Prussia. Those passing into the Gulf of Bothnia and the Baltic 

 Sea curve westerly so as to extend over the North Sea, English Chan- 

 nel, southern England, and the north of Scotland. England and Scot- 

 land are made to send off additional currents ; and the limit of the ice- 

 sheet reaches to west longitude 14, or where the shallow water begins 

 to deepen. The chart is designed to show the probable path of the ice 

 in Northwestern Europe during the period of maximum glaciation. 

 This area is about seventeen hundred miles wide and fifteen hundred 

 from north to south, and will hence compare favorably in size with 

 that of Eastern America. The phenomena of dispersion are explicable 

 upon the theory of the origin of the current from the central Scandi- 

 navian l'idge, supplemented by radial streams from the Scotch and 

 Welsh highlands ; and there is no evidence, unless upon the outermost 

 Hebrides, of any flow of polar ice into the European district. The ice- 

 masses have proceeded from higher to lower levels for the most part, 

 rising somewhat to pass over Denmark and southern England ; and 

 there is no essential difference between the Alpine and Scandinavian 

 areas save in size. 



All the glaciated districts can now be referred to definite areas, 

 separate from one another, and exhibiting grooves radiating from central 

 points and lines. They are, first, the small Alpine district ; second, 

 the Scandinavian, with the British additions ; third, the paleocrystic 

 sea of the polar regions ; fourth, Greenland ; fifth, Eastern America, 

 concerning which more will be said in the sequel ; sixth, the Rocky 

 Mountain areas, in which there were several groups of glaciers, con- 

 fluent north of the Columbia River. 



Maps will show how the several glaciated regions stand related to 

 one another. They are isolated, disconnected, though all situated 

 upon one hemisphere. Each was a center by itself. The ice mov- 

 ing from the central highlands made its way radially in all directions, 

 carrying detritus and scouring the ledges. The larger ones do not 

 vary greatly in their territorial dimensions. That of Eastern America 

 exceeds the others, especially if we add to it the Arctic archipelago, 

 where, owing to the high latitude, the oner de glace is nearly universal 

 with no great amount of motion. But we do not discover from this 

 delineation any confirmation of the notion of a general polar ice-cap, 

 which has furnished the ice for both the European and American gla- 

 cial sheets. The Scandinavian, Greenland, and American regions seem 

 to have been entirely independent of each other separated by deep 

 ocean-water. All of them must have undergone their intense frigid 

 conditions in post^Tertiary times, because of some astronomical cause 

 affecting the northern hemisphere equally throughout. We do not 

 find distinct glaciated areas upon the Asiatic side of the pole, because 

 the relations of land and water are unfavorable to the formation of 

 ice-sheets, but the temperature is and has been low enough. 



