the rough country in the rear of Lakes Huron and Superior, and the water parting between the St. Lawrence valley and Hudson's Bay. The height of land is really a tableland, diversified with innumerable lakes, large and small, but west of the Saguenay River, not distinguished by mountains possessing any considerable altitude. In the rear of the St. Lawrence, below Quebec, detached peaks of the Laurentides attain an elevation of 2,000, and even 3,000 feet. Forty miles from the coast, opposite Anticosti, they have an elevation of 3,200 feet, and on the great table land of the Labrador Peninsula there are isolated peaks at least 5,000 feet above the sea level. On the south of the St. Lawrence, the level valley of the river is from thirty to forty miles broad as far as the base of the prolongation of the Green Mountains of Vermont, in which range detached peaks attain an elevation of about 4,000 feet. The Notre Dame mountains in the District of Gaspé are very imposing; they vary in width from two to six miles, and in height from 2,000 to · 3,778 feet. Viewed as a whole, the entire valley of the St. Lawrence from Lake Superior to Quebec, may be regarded as occupying part of the north-eastern rim of the immense basin of sedimentary rocks which form the United States, a portion of Mexico and British America west of Lake Winnipeg. The broad and low Laurentides stretching from Labrador to the Arctic sea separate this basin from the northern one, in part occupied by Hudson's Bay.

THE SOILS OF CANADA.

The geological structure of different parts of this vast extent of country determines, to a considerable degree, the character of the soils which form the surface. The soils in the western part of the province are derived from the 'drift,' which is made up of the ruins of the crystalline rocks of the Laurentides and of the sedimentary rocks lying to the north of any particular locality or in its immediate neighborhood.

In the extreme western peninsula the rich clays consist of remodeled 'drift,' and are of lacustrine origin. In the valley of the St. Lawrence below Montreal, the clays are marine, and not unfrequently contain a considerable proportion of calcareous matter. Below Quebec, on the south shores, the soils are derived from the disintegration of the red slates found in that region, while in the eastern townships the drift and debris of the altered rocks, which distinguish that part of the country, form the surface covering. In the region of the Laurentides, the fertile belts or strips consist either of 'drift' or of the ruins of crystalline limestone, and soda and lime feldspars, but the area covered by arable soil in the rocky region of the Laurentides is comparatively very small, and necessarily limits the progress of settlement north of the St. Lawrence and great lakes. The area in Canada occupied by sedimentary rocks, where in general rich and fertile soils abound, is about 80,000 square miles; the region embraced by the crystalline rocks is about 240,000 square miles in extent, five-sixths of which may be said to be wholly incapable of cultivation.

ROCK FORMATIONS.

The whole of the peninsula of Western Canada, the valley of the St. Lawrence south of the Laurentides, the valleys and depressions in the peninsula of Gaspé, are more or less deeply covered with clays interstratified with sand and gravel, which belong to quarternary deposits, and in some parts are overlaid by alluvium. The region of the Laurentides alone exposes over the greater part of its vast extent, bare crystalline sedimentary rocks, the oldest, as far as is known, in the world, and named after the great river where they are developed on such a stupendous scale, the 'LAURENTIAN SERIES.'

Between the Post Tertiary and the base of the Carbonif erous, the entire series of sedimentary rocks is wanting in

Canada, with the exception of small patches of Tertiary Formations which have escaped denudation.

THE QUARTERNARY DEPOSITS.

The stratified clays, sands and gravels contain the remains of many species of marine animals, identical with those now found in the Gulf of St. Lawrence, often at an altitude of 500 feet above the level of the sea. Sixty-three species of marine invertebrates from the Post-Pliocene or Pleistocene clays of the St. Lawrence valley have been disinterred. The quarternary deposits form the soil of a large portion of the country. They contain clays suitable for the fabrication of red, white and yellow bricks; molding sands, tripoli, shell marl, bog iron ore, ochre, and in the eastern part of Canada they are overlaid by peat, which occupies depressions.

THE PALEOZOIC ROCKS.

If we suppose that the quarternary deposits were swept away, and the whole of the underlying rocks laid bare, the formations of Canada older than the post tertiary would be found to consist of the following series:

1. A small area of the Carboniferous.

2. The Devonian Series.

3. The Silurian Series.

4. The Huronian or Cambrian Series. 5. The Laurentian Series.

These rocks form part of the Great Southern Basin of North America; the geographical limits of Canada, while embracing a large portion of its northern rim, penetrate like a wedge towards its center, by means of the peninsular portion of the western part of the province. An anticlinal axis separates this basin into two subordinate divisions, the line of demarkation running from the valley of the Hudson towards Quebec. The western subordinate basin contains the great coal fields of the United States, the eastern portion

embraces those of New Brunswick and Massachusetts. "The rocks of these two basins present remarkable differ ences in their chemical and physical conditions. The formations of the western basin are nearly horizontal, and offer a perfect conformity, while in those of the east there is discordance between the upper and lower Silurian, and between the Devonian and Carboniferous formations. The strata of the eastern basin are moreover very much folded and contorted, and have in some parts undergone profound chemical and mineralogical changes."*

The highest formation in Western Canada is the Portage and Chemung group, or the upper portion of the Devonian Series, which includes the Hamilton group, the Corniferous limestone, the Oriskany sandstone, &c., of the New York geologists. In the extreme west of the province, where patches of the Portage group occur, extraordinary springs of petroleum have been tapped by boring to the depth of from 200 to 300 feet, on the summit of an anticlinal axis. The source of the petroleum is probably the underlying Corniferous limestone. The yield from four springs, which send pure petroleum about thirty feet above the surface of the ground, is estimated at fifteen thousand barrels a day. Lying beneath the Devonian Series are the Onondaga Salt Group, the Niagara limestone and the Medina sandstone of the Upper Silurian Series. Next follow the Middle Silurian rocks, represented by the Hudson River Group and Utica Slate, the Oneida Conglomerates not having been found in Western Canada. The Lower Silurian Series is represented in regular sequence by the Trenton, Black River, Birds-eye and Chazy limestones, succeeded by the Calciferous sand-rock and the Potsdam sandstone which rests upon the ancient crystalline rocks of Huronian or Laurentian

* Sketch of the Geology of Canada, by Sir W. E. Logan, F. R. S., and T. Sterry Hunt, F. G. S.

age. Tracks of a large crustacean are numerous in the Potsdam sandstone, coprolites occur in abundance at the summit of the Calciferous sand-rock, the succeeding limestones are very rich in fossils, and the Utica slate is distinguished by abundance of bitumen, which has been used as a source of oil derived from its destructive distillation, but not, commercially, with success. The Onondaga salt group furnishes gypsum and brine springs. The marbles of the lower limestones are susceptible of a fine polish, and hydraulic cement of the best quality occurs in many parts of the province.

The highest rock in the eastern basin is a millstone grit, which forms the base of the New Brunswick coal field. It occurs in the Peninsula of Gaspé, and is underlaid by Devonian sandstone of great thickness, (7,000 feet,) which reposes on limestone and shales of the Upper Silurian Series, resting upon rock of Middle Silurian age. Some members of the Lower Silurian Series are highly metamorphosed and developed to an extraordinary extent in the vicinity of Quebec and elsewhere, showing a thickness of 7,000 feet, and distinguished by metaliferous veins; hence, although of the age of the Potsdam sandstone and the Calciferous sandrock, they have been named the Quebec Group, also the Taconic system, and the Upper Copper-bearing rocks of Lake Superior. They are of vast economic importance, inasmuch as they form the great metaliferous formation of North America, containing gold, lead, copper, zinc, silver, cobalt, nickel, chromium and titanium. They are traceable from Gaspé to Alabama, under various designations, and thence to the west side of the Mississippi, through Kansas to Lake Superior, without suffering any diminution in volume. The copper ores in Eastern Tennessee and those of Acton in Lower Canada, belong to this important group, as well as the lead, copper, zinc, &c., of Missouri, and the copper of Lake Superior.

On the shores of Lakes Huron and Superior, the Quebec