GEOLOGY AND SCENEET OF NORTHEAST COAST 115 



across New Jersey, Pennsylvania, Ohio, Indiana, and so on 

 to the plains of the Upper Mississippi Valley and Northwest 

 Territories of Canada. The total area of this " Labrador" 

 or "Laurentian" ice-cap was over two millions of square 

 miles. In the central part its thickness grew to be at 

 least six thousand feet. There is evidence to show that even 

 Mt. Washington (6288 feet in altitude), together with all 

 other peaks of New England, was covered by the flooding 

 ice. 



Investigation much less thorough than has been given to 

 the Labrador glacier has suggested that similar, independent 

 ice-caps were formed on the heights of Newfoundland and 

 on the plateau northwest of Hudson Bay (the "Keewatin" 

 Glacier), each having centrifugal flow. 



The causes for the disappearance of the ice-sheets are 

 as stimulating to debate among glacialists as the conditions 

 that led to the growth of the glaciers. Fortunately for 

 a scenographic account of the Labrador, these intricate 

 theoretical questions need not detain us ; suffice it only to 

 note the fact that, after a period of prolonged activity, the 

 ice gradually melted away. Not an acre of the old ice has 

 been found on the mainland of North America. It is 

 possible that the Grinnell Glacier, the relatively diminutive 

 ice-cap of southern Baffin Land (Meta Incognita), repre- 

 sents a still lingering portion of the mightier glacial flood, 

 but so little is known of the Grinnell that a former connec- 

 tion of the existing and the vanished ice-sheet cannot be 

 asserted. On the contrary, it may be that the reported 

 twelve hundred square miles of ice on the Meta Incognita 

 belong to another independent centre of ice-accumulation. 

 The solution to this problem and the interest which always 



