OF THE RIVER SAINT LAWRENCE. 



25L 



of the basin of the St. Lawrence proper, eastward, beyond Three Rivers, and differs from 

 it no otherwise than in being tidal, and therefore, also, of greater breadth. As it is of no 

 particular interest in the discussion of the hydrography of the flowing waters of Canada,, 

 and as its limits are also prolongations of the limiting mountain ranges of the basin of the 

 St. Lawrence River proper, no further notice of it seems necessary, than to mention that 

 the influence of the tide is felt upon the surface of Lake St. Peter, a broad expanse of the 

 river, beyond the stated head of tide at Three Rivers. The St. Maurice River enters the 

 St. Lawrence not far below this lake, its embouchure being nearly on the boundary be- 

 tween tin; two first basins. This point is ninety miles above Quebec, where the lower 

 river, as it is called, commences. The Saguenay comes into it one hundred and ten miles 

 below Quebec; and one hundred and twenty miles still further down, at Point des Monts, 

 the estuary, widening suddenly on the north, may be considered as merging in the Gulf, 

 but the south shore moves forward in an unbroken curve for one hundred and thirty miles 

 more to Cape Gaspe. The whole length of the tidal basin may be therefore called four 

 hundred and fifty miles. The basin of the St. Lawrence proper is limited, both on the 

 northwest and on the southeast, by mountain ranges. That on the north is called the 

 range of the Laurentide Mountains. That on the south is called by various local names, 

 but may be termed the range of the Green Mountains. The Laurentide Mountains beffin 

 in Labrador, at the Straits of Bellisle, and run on in a southwest direction parallel in 

 several instances, spreading out southwards so as to form bold bluffs and mountains close 

 to the water's edge, as at Cape Tourment, which is sixteen hundred feet high ; they 

 range at an average distance back from the Gulf and river from twelve to fifty miles; 

 across the Saguenay and behind Quebec, across the St. Maurice and behind Montreal, up 

 the Ottawa to the Lac des Chats, a distance of at least seven hundred miles. They form 

 the northern background to all the pictures of the river scenery. They arc composed of 

 the oldest rocks known to geological science, and spread themselves at an average eleva- 

 tion of about two thousand feet above the sea, back from the front line just described, 

 over a table land of forests and lakes, far towards the waters flowing into Hudson's Bay; 

 westward, beyond Lakes Huron and Superior; and southward, across the Ottawa to the 

 foot of Lake Ontario, and across the St. Lawrence at its outlet from the lake, into Northern 

 New York, filling up the country west of Lake Champlain with mountains, some of which 

 exceed five thousand feet in height above the sea. The western or head line limit of the 

 St. Lawrence River basin is at the foot of the Laurentian rocks, from Lac des Chats on 

 the Ottawa, to the Thousand Islands on the St. Lawrence. Its northern border is formed 

 by the Laurentide Mountains north of the Ottawa, and its southern by the Laurentian 

 Adirondack Mountains of New York, along the Canada Boundary Line. The triangular 

 space between the Ottawa, and the St. Lawrence, with its apex at Montreal, is a great 



