﻿60 ST. LAWRENCE WATER-SHED. 



surround them is occasionally greater, giving the 

 district a hilly aspect. The highest of these 

 eminences does not overtop Thunder Mountain and 

 some other basalt-capped promontories on Lake 

 Superior, and had not the silurian strata, which, 

 judging by the patches which remain, once covered 

 the gneiss and granitic rocks nearly to their summits, 

 been removed, the country would have been almost 

 level, and would have formed part of the rolling 

 eastern slope of the continent, above whose plane 

 the highest of the hills on Lake Superior scarcely 

 rises. The summit of this water-shed of the St. 

 Lawrence basin, commencing towards the Labrador 

 coast, runs south 52° west, or about south-west half- 

 west, at the distance of rather more than two 

 hundred miles from the water- course, until it comes 

 opposite to that elbow of the line of the great lakes 

 which Lake Erie forms ; it then takes a north 51° 

 west course, or about north-west half- west, towards 

 the north-east end of Lake Winipeg, and onwards 

 from thence in the same direction to Coronation 

 Gulf of the Arctic Sea. The angle at which the two 

 arms of this extensive water- shed (but no where 

 mountain ridge) meet between Lakes Huron and 

 Ontario is within half a point of a right one, and 

 the character of the surface is everywhere the same, 

 bearing, in the ramifications and conjunctions of its 

 narrow valleys filled with water, no distant resera- 



