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those of small size. Instead also of belonging to the districts in the west and south, they are all (as far as can be ascertained) from the east and north. The majority are primitive, but of characters so common that it seems impossible to assign their home. The red sandstone of the lower regions on the east is usual on the upper level of this river, together with the milky quartz rock of the outlet of Lake Ontario, and the arenaceous limestone from the same quarter; the latter characterised by micaceous scales, and its peculiar fossils—the plagiostomæ, &c.

It is a remarkable fact, and supplies another proof (if it were wanted) of the great chasm being the work of the present river, that there is scarcely a travelled rock in it. I met with one only-a large fragment of gneis, full of small garnets, quite that of the Portage “ Chaudiere des Francois" on the Lake Nipising. It may have been brought from the upper lakes in the blocks of ice which every spring are precipitated over the Falls,

The chertzy limestone at Black Rock, already described, extending into Lake Erie, two patches of the brown limestone beneath it, a little south of the village of Waterloo, on the British shore, and a small interval of argillaceous shale, below the Gorge of Queenston, are the only fixed rocks on the River Niagara, out of the chasm.

In that deep and often mural defile its stratification is beautifully developed, although seldom accessible. An examination of the face of the “ Parallel Ridge” (through which it is cut) along its course to the head of Lake Ontario, shews that similar rocks underlay the districts in the west for many miles ; and we shall find them to continue easterly to the primitive ranges at the east end of Ontario. : The walls of the chasm are composed (beginning from above) of the brown limestone over which the Falls pass. This is incumbent on calcareous shale, which, again, rests upon a series of arenaceous rocks, highly ferruginous in the superior portions, and in the inferior very argillaceous, and contain springs of brine. Of this last kind is the red shale, supporting the village of Queenston, and not exceeding two feet above the level of Lake Ontario,

The brown limestone, just mentioned, supports the chertzy variety at Black Rock. Under the same relations that it observes here it crowns the parallel ridge throughout the southwestern half of Lake Ontario to its head, and of course underlays the country on its south. It is from twenty-five to twentyseven yards thick, near the Falls, including some ledges contiguous to, and behind the precipice.

It is commonly fetid, of a dark brown colour, but sometimes light grey. Its texture is fine and coarse grained, and in certain layers is full of minute ragged cavities. The layers are often exceedingly thick*. Beneath the Table Rock, the lowest is thirty feet thick, or thereabouts ; but subdivides suddenly close at hand. At the Upper Staircase, on the British side, the top stratum is sixteen feet in thickness; but in like manner it breaks up in both directions into a number of layers from one to three feet thick. They are very massive and light coloured near the summit of the “ Parallel Ridge," one mile and a half west of Queenston. The stratum, noted as being nearly thirty feet thick, is traversed horizontally by at least six singular fissures or rifts, whose upper and under surfaces interlock firmly by rugged masses and points, overlying each other exactly as in the sutures of the cranium. The parts in contact are extremely smooth, bright, and black or brown. The prominences, sometimes one and two inches long, are usually fluted or grooved longitudinally. In hand specimens, with a little violence, this kind of dove-tailed joint can be taken asunder, and replaced. I did not observe it in the other layers around the Falls, but it occurs repeatedly down the chasm, and is very distinct in the grey limestone on the way to St. David's.

Some curious appearances present themselves at the junction of this limestone with the black shale below,—the latter there becoming rapidly thicker and browner. The bottom of the limestone, for a foot or so, is occupied by flat masses of black limestone, (apparently of the layers below,) oblong, almost all lying horizontally, with their edges rubbed off, but never more than six inches in length. They are numerous, but usually separate. For several feet upwards, minute fragments (mere dots) of this limestone pervade the stratum.''-'.

* It contains two small caverns: one is on the British side, a mile and a half below the Falls.

I have seen this appearance only under the Table Rock, This brown limestone has been named “geodiferous" by Mr. Eaton, from its abounding remarkably in drusy cavities and geodes, lined with various crystallizations. At the Falls, they are rare in the lower layers ; very numerous in the upper third; and, near the top, often constitute the greater part of the rock. These crystallizations are of pink pearl spar-nearly cubic rhombs ; trihedral and hexedral pyramids of calcspar, (hyaline,) foliated selenite, purple fluor, crystals of quartz, and slender prisms of the sulphate of strontian. These minerals are either solitary, or grouped together in the same geode. Considerable masses of yellow blende are common, imbedded (with a quartzose covering) in the limestone, singly and with galena : occasionally, the most ordinary form of the crystal of the former is met with in the geodes. Large and small lumps of granular gypsum are frequent in the lower layers, but not so above—their place seeming to be taken by a vast number of siliceous nodules, from two to seven inches in diameter. These are often nearly round, with a dark rough surface; and are formed of concentric layers of calcareous flint, which are either compacted into a greyish-veined substance, or are, in parts, distinct; their surfaces being lined with crystals of quartz, selenite, and calcspar; the latter occasionally of a bright salmon colour, or a delicate yellow. I believe them all to be the work of madrepores, as their cells are often very evident here; and still more so at Rochester, on the Genesee river. These nodules, the geodes and their minerals, are almost altogether wanting in the vicinity of Queenston, and in the whole course of the “ parallel ridge,” to Grimsby at least; but they are plentiful on the south side of Ontario.

Organic remains in this limestone are very rare at the Falls. At the Table Rock, I met with a few terebratulæ, many hollow casts of the fragments of encrinital columns, and one turbo. Lieutenant Bolton found another turbo. There are some nests of favasite. As well as the very unfavourable circumstances of position, &c., would allow me to observe, little change in this rock takes place on the Canadian side, to within about a mile and a half of Queenston; from which distance to the gorge of the chasm it occupies a retreating cliff, almost, if not altogether, unapproachable. The inequalities, however, of the brow of the mountain, about Brock's Monument*, and along the summit of the cliff, relieve us from these difficulties. The broken platforms and short ledges of this brown limestone which here prevail, shew it to be at least seventy feet thick. It is full of encrinital fragments-many of them coloured of a fine red, like those of Lockport, on the south shore of Lake Ontario. The large bicarinated terebratulæ of Lake Erie are not uncommon; and the debris of indeterminable trilobites, similar to that of Lakes Huron, Sincoe, and Ontario. mi I saw many turbinoliæ, ramose millepores, retepores, cellular madrepores, one turbo, and well-marked productæ. The suture-like fissures noticed at the Falls are met with ; and, I think, in the same stratum. I did not see here one nodule of gypsum or of silex: but the limestone of the Ridge, one mile and a half west, at the same height, has numerous irregular cavities, lined with crystals of quartz and calcspar; and imbedded in it are the hollow encrinital moulds before spoken of, and a few turbinoliæ. In the lower layers here, too, are the fragments of trilobites, with terebratulæ, corallines, &c.

Examining the Ridge at Wolverton's, thirty miles hence, and a mile or more west of the village of Grimsby, I found no change whatever in this limestone; but I saw none of the nodules above mentioned, probably from the layers in which they chiefly prevail being concealed by herbage. The rock on which this brown limestone is placed, is a black argillo-calcareous shale. It is visible throughout the chasm; along the face of the Ridge to Grimsby, on the west, it can scarcely be seen, for the herbage covering it, nor did I meet with it. I think it positively wanting at Wolverton's. The continuation of those heights easterly, display it in many places; among which Lockport and the Genesee Falls are the best known. vi It is very shaly at the Falls of Niagara, but has browner layers, six to twelve inches thick, interleaved at regular dis

* This fine column is near the highest part of Queenston Heights.

tances. It is homogeneous, and effervesces on exposure to acids. "It is often spotted yellow by sulphur, which, under the arch of the Falls, may be gathered in tufts of very small acicular crystals. On this river, and in its vicinity, it does not contain a trace of animal or vegetable life; but at the two places above spoken of, it abounds with new and important kinds of the former, as well as an abundance of the more common. The thickness of this stratum has not been ascertained on the river Niagara; nor can it be, I think, without much trouble and expense. Its inferior connections have not been examined at this place, further than to determine, that the next rock succeeding below is a series of sandstones, which I shall immediately proceed to describe ; leaving the additional facts respecting the calcareous shale to be brought forward when on the geology of Lake Ontario.

These sandstones are found throughout the country, west and south of Lake Ontario, little changed in mineral characters or geological position. I do not think that their contents, if thoroughly examined, would present any great differences; but at present, certain organic remains seem to be confined to particular localities. They are every where distributed into the following subdivisions. The first species (from above) is a grey, or white quartzy sandstone (“ferriferous sand rock” of Eaton). It is followed successively by a red argillaceous slaty sandstone, (“ferriferous slate" of Eaton ;) a hard, grey caleareo-argillaceous sandstone, (“ grey band” of Eaton ;) and a soft red and green argillaceous shale, to which Mr. Eaton restricts the property of being saliferous, and names it "saliferous rock."

I am inclined to consider all these strata, and their superincumbent limestones, to have been deposited nearly at the same time. They are all conformable to each other, and rarely betray marks of disturbance at the connecting planes. The contained fossils indicate no change of eraấthe two upper sandstones sometimes alternate. All these sandstones are finely displayed at one place or other in the chasm ; and best on the American side, in the middle and lower parts. Near the Falls, the debris of the surrounding cliffs creeps up nearly to the top of the black shale, and only permits a little of the

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