294 MINERALS AND GEOLOGY 



broadly, the older rock-formations lie in the northern and eastern 

 portions of the Dominion ; the- newer, in the west.* 



PROVINCE OF ONTARIO. 



INTRODUCTORY NOTICE. 



The southern limit of this Province extends westward along the 

 St. Lawrence River, from a few miles above the junction of the St. 

 Lawrence and the Ottawa, through Lake Ontario, and the greater part 

 of Lake Erie to the River Detroit. Its south-western and western 

 limit runs through Lake St. Clair, Lake Huron and Lake Superior 

 as far as the mouth of Pigeon River, and from thence to the 

 north-west angle of the Lake of the Woods. Its north-west and 

 northern boundary runs from that point to Winnipeg River, and then 

 north-easterly by Lac Seul and St. Joseph's Lake, along the Albany 

 River to James' Bay, the southern point of Hudson's Bay ; and its 

 eastern boundary passes from the latter directly south to Lake Tem- 

 iscamingue, and from thence down the Ottawa to near the junction 

 of that river with the St. Lawrence. The area of the Province (ex- 

 clusive of the portions of the great lakes within its boundary) is com- 

 puted to equal 181,SQO square miles. 



On passing south-westerly, parallel with the River St. Lawrence 

 from the County of Glengarry, the eastern extremity of Ontario, we 

 traverse a gently undulating district, rising from about 100 to 250 

 feet above the sea-level and extending from the Province boundary to 

 the vicinity of Brockville. This district is underlaid by limestones 

 and sandstones of Silurian and Cambrian age, and is of good fertility. 

 The Nation River flows through it in a north-easterly direction and 

 falls into the Ottawa. A little west of Brockville, a gneissoid, crys- 

 talline district, comparatively wild and rocky, is traversed for about 

 40 miles to the neighborhood of Kingston. This extends northwards 

 into the great Archaean region, which it connects, south of the St- 

 Lawrence, with the mountainous district of the Adirondacks. West 

 of Kingston, a gently-undulating, agricultural district, underlaid 

 mostly by Lower Silurian limestones, is again traversed. This ex- 

 tends, with an avergage elevation of about 250 feet near the shore of 



* The rock-formations of Ontario and Quebec alone come under review in the present 

 work. A synopsis of the geology of the other Provinces will be found in the author's " Outline 

 of the Geology of Canada. 



