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The scratches are generally parallel to the general direction in which the diluvium has moved.

Similar appearances have been lately described by Mr. Murchison, Sec. Geol. Society, as occurring on the Braambury and Hare hills, the highest in geological position of the interesting Brora district in Sutherlandshire. These are celebrated for their quarries of siliceous white sandstone, abounding in fossils, and exhibit upon their sides and summits, distinct traces of a strong diluvial current, which has swept away their covering matter, and deposited in the plain of Clyne Milltown, a mass composed of the debris of the denuded hills, mixed with boulders of the coarse red conglomerate. A large portion of the turf having been recently removed, the surface of the rock is now seen to be scored with parallel lines, precisely similar to those observed in other places. And in this case, although the surface of the ground is very unequal, and the dip and bearings of the denuded strata vary considerably, the direction of the markings is uniformly from N.N.W. to E.S.E.

That these diluvial actions reached the summits of the lofty mountains, is evident from the boulder blocks of Mont Blanc thrown over on the high acclivities of the Jura chain. "The Alps and Carpathians, and all the other mountain regions I ever visited in Europe," says professor Buckland, "bear in the form of their component hills the same evidence of having been modified by the force of water, as do the hills of the lower regions of the earth; and in their valleys also where there was space to afford it a lodgment, I have always found

diluvial gravel of the same nature and origin with that of the plains below, and which can be clearly distinguished from the postdiluvian detritus of mountain torrents or rivers. The bones of the

mastodon are found in diluvial gravel, in the Camp de Geans, near Santa Fe de Bagota in South America, 7800 feet above the level of the sea; and in the Cordilleras at an elevation of 7200 feet, near the volcano of Imbaburra, in the kingdom of Quito. M. Humboldt found a tooth of an extinct species of fossil elephant at Hue-huetoca on the plain of Mexico. Our high mountains in Europe are so peaked that animal remains though drifted round their summits, could hardly be expected to lie upon them, but would be washed down their steep slopes.

In central Asia, bones of horses and deer which were found at a height of 16,000 feet above the sea, in the Himmala mountains, are now deposited at the Royal College of Surgeons in London. They were got by the Chinese Tartars of Duba, in the north face of the snowy ridge of Kylas in lat. 32° N., out of the masses of ice that fall with the avalanches, from the regions of perpetual snow. preceding facts attest, that "all the high hills that were under the whole heavens were covered," by the waters of the deluge.

The

There is a class of phenomena, clearly indicative of diluvial action, usually called valleys of denudation, to which we have already briefly adverted. Two excellent memoirs have been written upon them by Professor Buckland, in the Geological Transactions, vol. V. and Second Series, vol. I.

Hutchinson and Catcott showed long ago, that

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the surface of the earth in many places, where it is at present furrowed by valleys, must have been formerly continuous: and this in innumerable instances where streams do not exist at all; in many chalk downs for example, or where the existing streams, as has been demonstrated already, are quite inadequate to the effect. Thus in a system of superposition such as is here represented, the

portions of the beds, a, b, and c, at present detached from each other, must once have been continuous : d has also been partially cut through, and e has been left untouched, merely because the excavation did not cut deep enough. The coasts of Dorset and Devon exhibit beautiful illustrations of this kind; the beds which are there intersected by valleys, nearly at right angles to the coast, being so different from each other, and so unlike in external aspect (chalk, green sand, oolite, lias, and red marl,) that there is no difficulty in tracing the continuation of the series on the opposite sides of the valleys, and no doubt of their former connexion. On passing along the coast to the east of Lyme and Sidmouth we cross nearly at right angles a continual succession of hills and valleys, the southern extremities of which are abruptly terminated by the sea: the valleys gradually sloping

into it, and the hills being abruptly truncated, and often overhanging the beach or under cliff, with a perpendicular precipice. The streams and rivers that run through them are short and inconsiderable, and incompetent even when flooded to move any thing more weighty than mud and sand. There is usually an exact correspondence in the structure of the hills which enclose each valley; so that whatever stratum is found on one side, recurs on the other side in the prolongation of its plane. When ever there is a want of correspondence in the strata on the opposite sides of a valley, it may be referred to a change in the substrata upon which the excavating deluge had to exert its force.

If we examine the valleys that fall into the bay of Charmouth, from Burton on the east to Exmouth on the west, viz. that of the Bredy, the Brit, the Char, the Axe, the Sid, and the Otter, we shall find them all to be valleys of diluvian excavation; their flanks being similarly constructed of parallel and respectively identical beds; and the commencement of them all originating within the area, and on the south side of the escarpment of the green sand. The fact of excavation is evident from simple inspection of the manner in which the valleys intersect the coast, on the east of Sidmouth and the east of Lyme; and it requires but little effort, either of the eye or the imagination, to restore and fill up the lost portions of the strata that form the flanks of the valleys of Salcomb, Dunscomb, and Branscomb; or of Charmouth, Seatoun, and Bridport.

From the correspondence pointed out by Mr.

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William Phillips, between the strata of Dover and the hills west of Calais; and by Mr. de la Beche, between the strata of the coast of Dorset and Devon, and those of Normandy, it may be inferred that the English Channel is a submarine valley, which owes its origin in a great measure to diluvial excavation, the opposite sides having as much correspondence as those of ordinary valleys on the land. Its depth is less, indeed, than that of the majority of the inland valleys which terminate in the bay of Charmouth.

In conclusion, Professor Buckland justly observes, that "though traces of diluvian action are most unequivocally visible over the surface of the whole earth, we must not attribute the origin of all valleys exclusively to that action. In such cases as we have been describing, the simple force of water, acting in mass on the surface of gently inclined and regular strata of chalk and oolite, is sufficient for the effects produced; but in other cases, more especially in mountain districts (where the greatest disturbances appear generally to have taken place), the original form in which the strata were deposited, the subsequent convulsions to which they have been exposed, and the fractures, elevations, and subsidences which have affected them, have contributed to produce valleys of various kinds on the surface of the earth, before it was submitted to that last catastrophe of an universal deluge which has finally modified them all.* See Valleys of Elevation, p. 343.

To the preceding geological proofs of the universal deluge, we must add our zoological witnesses,

* Reliquiæ Diluvianæ, 2d Edition, p. 258.