GEOLOGY AND SCENERY OF NORTHEAST COAST 119 



Among the first evidences to convince the observer of 

 the extent, power, and recency of the glacial invasion is the 

 character of the rock-ledges on all the coastal belt from 

 Belle Isle to Cape Mugford. In pre-Glacial times there 

 must have existed a deep soil and a heavy layer of weathered 

 and decomposed rock over this entire area. The word 

 "must" is none too strong if the Labrador mountains had 

 wasted down after the manner of other old ranges, and 

 there is every ground for believing that such was the case. 

 In other words, we can find an analogy to the pre-Glacial 

 range of the Labrador in, for example, the unglaciated 

 southern Appalachian Mountains in which the granites 

 and schists are so altered by secular weathering that the 

 rock is friable and rotten for depths of hundreds of feet 

 below the present surface. 



In Georgia or northern Alabama it can be proved that 

 some of the rock-bands are weathering more rapidly than 

 others; over the former the blanket of disintegrated rock 

 is deeper than elsewhere. So it doubtless was in Labrador. 

 When the ice-cap became thick and powerful, it slowly 

 scoured and planed away the ancient soil with the under- 

 lying layer of rotted rock. Under the enormous weight 

 of the cap a half mile or more in thickness, the ice moulded 

 itself into all the depressions. As the easily removed 

 blanket of decayed rock was carried northeastward out to 

 the Atlantic basin, not only was the general level of the 

 country lowered, but it was lowered faster where the pre- 

 Glacial decay of the rocks had been most pronounced. 

 The energy and duration of the glacial scouring were such, 

 that apparently all of this loose material was removed, 

 leaving smoothed, hummocky hills and ledges of fresh, 



