7 



I. 

 THE LAURENTTAN REGION. 



The great tract of country occupied by the Lau- 

 rentian rocks has for its southern boundary the 

 limits already assigned, and stretches northward to 

 the boundary of the province, which is the height of 

 land dividing the waters of the St. Lawrence basin 

 from those of Hudson Bay. Its area is about 200,000 

 square miles, or six tenths of the whole land of the 

 province. This region is composed exclusively of 

 crystalline rocks, for the most part silicious, or gra- 

 nite-like in character, consisting of quartzite, sye- 

 nite, gneiss and other related rocks. These are % 

 broken up into ridges and mountain peaks, gene- 

 rally rounded in outline and covered with vegeta- 

 tion. The summits in the neighbourhood of Quebec 

 are some of them from 2,000 to 2,500 feet in height, 

 and in other parts attain 4,000 feet or more ; but the 

 general level of this region may be taken at about 

 1 ,500 feet above the sea, although it is much less in 

 the narrow belt which crosses the province east of 

 Kingston. Through the hard rocks of this region 

 run numerous bands of crystalline limestone or 

 marble, which from their softness give rise to val- 

 leys, often with a fertile soil. The hill-sides are 

 generally covered with little else than vegetable 

 mould, which sustains a growth of small trees, 

 giving them an aspect of luxuriant vegetation. But 

 when fire has passed over these hills, the soil is in 

 great part destroyed, and the rock is soon laid bare. 

 In the valleys and lower parts of this region how- 

 ever, there are considerable areas of good land, 

 having a deep soil, and bearing heavy timber. These 

 are the great lumbering districts of the country. 



