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Bersimis, and contained 31 per cent. of magnetic grains. The unpurified ore, which was mingled with a considerable amount of quartz sand, and some garnet, amounting together to about 17 per cent., gave by analysis about 40 per cent. of iron, and 15 per cent. of titanium, besides a proportion of manganese greater than the iron sands from the lower St. Lawrence."

We have not space to make extracts from the other reports, which are chiefly filled with local details of great value as contributions to the Geology of Canada, but affording few points of popular interest.

If any fault can be found with this Report, it is in the small amount of Paleontology which it contains; but this, it may be supposed, is to appear in the separate reports or decades of the Palæontologist of the Survey. The present Report, it will be observed, belongs to what may be called the transition period of the Survey the work done having been in great part under the directorship of Sir William Logan, but the issue of the Report being under that of Mr. Selwyn; who will, no doubt, in the large field now presented by the Dominion, prosecute the great work of the Survey with renewed energy and success, and render it even more creditable, if possible, to Canadian science.

J. W. D.

ON THE SURFACE GEOLOGY OF NEW BRUNSWICK. BY G. F. MATTHEW, ESQ.

(Read before the Natural History Society of New Brunswick, April, 1871.)

PART I.-THE GLACIAL EPOCH.

At the end of Prof. L. W. Bailey's Report on the Geology of the Southern part of New Brunswick (Fredericton, 1865,), will be found a few pages giving a very brief outline of its superficial geology. I now propose to consider the subject at greater length, and to record such observations as have been made in this region since the date of that report.

The Unmodified Drift being the most widely distributed of the superficial deposits in this Province, and that from which the materials of the later ones have been derived, a description of it

and of the related phenomena of striation, will naturally form the subject of this paper.

Of the Triassic period some few monuments still remain in Southern New Brunswick. Scattered patches of red sandstone, resting unconformably upon the Coal Measures in the eastern part of Saint John County bear witness to the former existence of an extensive basin of these rocks, which once occupied the Bay of Fundy depression and extended eastward into the area. occupied by the waters of the Gulf of St. Lawrence. These soft red rocks are monuments also of the enormous amount of denudation which the region underwent in subsequent ages; for it is only where they have been protected by ridges of hard metamorphic strata, or by the capping of basalt with which they are covered at a number of places, that any vestiges of these soft sandstones remain, around the Bay above named. Between the epoch of the Trias and the glacial period long ages elapsed which, except in the wearing away of the older formations, are not known to have left in Acadia any indications of their passage. During this interval the deposition of the Oölite, Chalk, and Tertiary formations was proceeding in Europe, and extensive accumulations were spread over wide areas in North America. They are to be found on both slopes of the Alleghanies and the Rocky Mountains.

The fossil fruits of Brandon, Vt., and the remains buried in the crumbling cliffs of Martha's Vineyard off the Southern coast of Massachusetts prove that a subtropical climate prevailed in this part of America during a part of the Tertiary Age. That such climatic conditions existed here at a period geologically so recent, would, to one who considers only the present range of temperature, seem highly improbable; but that this was the case is abundantly shown by the geological discoveries in the western part of the continent and in Iceland, where the remains of plants and animals of these intervening ages have been found. Not only does the fauna indicate the prevalence of a mild temperature in high latitudes during this period, but the character of the vegetation, in a great part of British America, was such as is now to be met with only in subtropical and warm temperate regions. Palms, cinnamon trees, and magnolias are known to have grown on the Upper Missouri and in British Columbia, and the genus Sequoia, to which belong the giant trees of California, with many species of hardwood (deciduous) trees as far north as Iceland.

The remarkable Miocine flora of this island has been studied by Prof. Heer, who concludes that at this period, evergreen forests must have extended to the pole. In Europe there are indications of a gradual refrigeration of the globe throughout the time of the Pliocene, but in Acadia, where this formation is wanting, we find the earlier tertiaries succeeded by the Boulder-Clay, a formation indicating climatic conditions of extreme vigour. As far south as New Jersey this deposit is of purely glacial origin, according to Prof. Dana and other New England geologists, but in the Middle and Southern States the evidence of ice-action is not so marked. Much attention has been given to the study of glacial phenomena over large areas in America, but geologists are not yet agreed as to the causes of some of them. Prof. J. S. Newberry, in an able article read before the New York Lyceum of Natural History,* contends for the former existence of a great continental glacier over all the region included in the hydrographic basin of the St. Lawrence and Red rivers. To this cause he ascribes the excavation of the basins of the Great Lakes (except Lake Superior) skirting the Laurentian hills from the State of New York to the valley of the McKenzie River in British America. He conceives that toward the close of the glacial epoch a great freshwater sea filled the central part of the area, extending eastward as far as the Adirondac mountains in the State of New York; and that it was bounded on the south by the water-shed between the streams which flow to the lakes, and those which seek the Mississippi, and northward by an extensive glacier resting upon. the Laurentide hills. He supposes that the Erie clays spread over this area, were deposited in an immense lake during a long period of slow subsidence. At a subsequent time, as the land rose again and the waters of the lake gradually drained away, the Orange sand and other surface deposits were produced by the erosion of the clay beds, as different parts of the lacustrine area were brought under the influence of the waves.

The Orange sand of the Mississippi basin, however, appears to have had a different origin, for Prof. E. Hilgard, who had made extensive explorations in Louisiana and Texas, states that it was swept down the valley of this river by powerful southerly currents.

Both Sir W. E. Logan and Dr. Newberry assert the cotemporaneous origin of the Erie clay of the west and the Champlain (or

Published in The American Naturalist, June, 1870.

Leda) clay of eastern Canada; and Dr. Dawson has identified these with the Marine clays of Maine. The latter are found in all the valleys near the sea level both in that State and New Brunswick, but have not been traced to any considerable height above the sea. All these clays in New England and the eastern Provinces of Canada are of marine origin, but the Erie clays were probably deposited in fresh-water. In New England as well as Acadia there are masses of superficial materials which underlie these marine clays, and should therefore be older than the Erie clay. Dr. Newberry does not appear to recognize them in the region underlaid by this deposit. These older masses of loose materials present in New Brunswick all the features of unmodified drift, and reach to the tops of the highest hills in the southern counties of that Province. While all the other surface deposits in their arrangement betray to a greater or less degree the sorting power of water, this alone, so far as has been ascertained, is unstratified throughout. It consists of clay and sand promiscuously mingled. These finer materials enclose numberless striated stones and angular fragments having no definite arrangement in the mass, but irregularly distributed throughout it. For a height of two hundred feet above the sea, the Boulder clay has been greatly modified by the action of waves and currents during a period of slow subsidence, and in the valleys it is covered with beds of fine clay.

THE CONTINENTAL GLACIER.-Two theories have been advanced to explain the phenomena of drift, namely that which attributes them to the action of icebergs and ocean currents, and that wherein glacier action plays an important part. If the latter be ignored, it would seem no easy matter to account for some of the characteristics of the Drift in this region, such as the smoothing and furrowing of low-lying ledges under the lee of continuous hill ranges; the striation of the undersides of ledges; the transverse grooving of narrow valleys, etc. Since the topography of the region is not favourable to the formation of local glaciers, there being no high mountains in or near it, if the Acadian drift resulted from glacier erosion, the glacier would have been a widespread sheet of ice, covering the whole surface of the country, similar to those of the Antarctic continent, or of Greenland. Rivers of ice flow down to the sea-side from the wide fields of compacted snow which covers a large part of the country last named; large masses of these frozen streams are detached at the coast, and

floating southward on the Arctic current along the Atlantic coast, add the distributing power of bergs to that of glaciers.

The degree of cold necessary to bring such an icy covering down to the latitude of St. John (N.B.) does not seem more improbable than the contrary amount of heat which in the preceding age enabled palms to flourish in New England and perhaps in Acadia also.

In an article on the Arctic and western plants of this region, which I had the honour to read before you two years ago, it was shewn that the mean annual summer temperature of this city was nearly two degrees lower than that of Thunder Bay on the north shore of Lake Superior. Undoubted indications of the former existence of glaciers on the north shore of that lake were seen by Prof. L. Agassiz; and Sir. W. E. Logan also alludes to similar instances observed by him. He considers glaciers to have been one of the chief agents in excavating the great lake basins.* If, during the glacial period the isothermal lines of the continent moved southward at an equal ratio in the east and west, we might readily admit that glaciers existed here as well as on the great lakes of the St. Lawrence basin.

Rigid as ice under ordinary circumstances appears, it is now well known that it possesses a certain amount of plasticity. Rendu, Agassiz, Forbes and others, who have carefully studied the Alpine glaciers, have clearly demonstrated the existence of this property in glacial ice. It enables the ice to accommodate itself to the inequalities of the surface on which it rests, and to slide down the ravines and narrow valleys of the mountain side, bearing along with it trains of boulders and loose masses of stones and earth. The rate at which glaciers move is very variable, being governed by the slope of their beds and the obstacles met. by the moving ice, but it may be roughly set down at from nine inches to a yard daily for the majority of the Swiss glaciers. Glacier motion is analogous to that of rivers. Where the sheet of ice is broad and the slope moderate, the motion is slow, but where the ice passes through narrow gorges the rate of motion is accelerated. Another point of resemblance to rivers is the motion acquired in passing around curves, the strength of the current being thrown-both in the case of glaciers and rivers on the outside of the curve. The momentum of ice in motion causes it

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Report of Progress, Canadian Survey, 1863, page 889.

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