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, 
