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cient geographical information. He describes the steppe extending between the Black Sea and the Caspian as

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lying at an extremely low and generally uniform level: it is marked (he proceeds) by an extreme want of fresh water, and is covered with sand and recent shells, such as are now found in the neighbouring scas. lakes and pools which it contains are mostly salt, and the scanty vegetation of the steppe consists of such plants only as are found with us on the sea coast, or which are of a like nature. The rock under the superficial sand is a hard clay, sometimes left bare.'*

Mr. Strangways has traced on the map accompanying his memoir the supposed former communication of the Black Sea with the Caspian, and of the latter with the salt lake, Aral,

according to which there must formerly have been either two inland seas separated by land in the neighbourhood of the Bosphorus, or the Mediterranean must have extended to the interior of Asia as far as the low steppe continues; and in that case its eastern shore would have been the high land which, in the steppe of the Kirghis, connects the Altay with the Himalaya mountains. Many considerable islands and peninsulas would have been thus formed; such as the Crimea, Kharizm, the Beshtan, &c., for the bed of a, strait is said to be traced across the isthmus of Perecop, including the steppe of the Dnieper on the north, and a part of that of the Crimea on the south; the lake Aral would have been joined by narrow seas with the Caspian on the north-west, and perhaps also on the south-west, &c.'

We must be satisfied with referring our readers to the author's own remarks on the illustration of several ancient geographical accounts and traditions afforded by these geological facts.

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No one can reflect on the above statements without being tempted to inquire whether the causes now in action are, as Dr. Buckland has supposed, the last expiring efforts of those mighty disturbing forces which once operated;' or whether, as Hutton thought, they would still be sufficient in a long succession of ages to reproduce analogous results. The opinion repeated by M. Cuvier in his last publication, that it is in vain to search in the forces now acting on the surface of the earth for causes sufficient to produce revolutions and catastrophes of which the traces are exhibited in its envelope,' is entitled without doubt to the more respect, as it seems to have been adopted by many in these later times, when additional facts have been so industriously accumulated. The total amount of change that has fallen under the observation of mankind in the course of 3,000 years is, however, so small, that the final decision of this question may certainly be regarded as incalculably remote, and indeed we can be content, for our part, to waive the speedier * Page 37. + Vindicia Geologicæ, p. 5. Cuv. Discours sur les Rev. &c. p. 41. KK 3

solution;

solution; for we are not so warmly interested in favour of any theory, as to wish, with King Henry,

— that one might read the book of fate

And see the revolution of the times

Make mountains level, and the continent,
Weary of solid firmness, melt itself

Into the sea.'

But in the present state of our knowledge, it appears premature to assume that existing agents could not, in the lapse of ages, produce such effects as fall principally under the examination of the geologist. It is an assumption, moreover, directly calculated to repress the ardour of inquiry, by destroying all hope of interpreting what is obscure in the past by an accurate investigation of the present phenomena of nature.

Those naturalists who have prosecuted with the greatest success the study of fossil remains concur in opinion that the earth during the deposition of the secondary strata was not in a state of chaotic confusion. There are proofs of occasional convulsions, but there are also proofs of intervening periods of order and tranquillity. The notion of a continually decreasing energy in nature's power to modify and disturb the earth's surface first originated in the observation that strata of the highest antiquity have suffered the greatest and most general derangement. But such must be the necessary effect of the uniform action of the same cause throughout a long succession of ages; and the frequent unconformability of strata clearly shows that disturbances have taken place at many and at different periods. There would perhaps have been some weight in the argument if the derangement of recent deposits were not merely of more partial occurrence, but invariably on a scale of inferior violence. But the fact is far otherwise. We find the chalk in Ireland extensively intermixed with trap, and in Hampshire thrown together with more recent formations into a vertical position. Beds of the purbeck series in Dorsetshire, and of the plastic clay in the Isle of Wight, are contorted in the same manner as primary clay slate. In no part of Europe are effects of disturbance displayed on so stupendous a scale as in the Alps. Yet the date of this convulsion is, geologically speaking, extremely modern, for marine strata as recent as the green sand, chalk, and even some tertiary formations are discovered in this chain at an elevation of more than ten thousand feet above the level of the sea. Professor Buckland has remarked that these Alpine tertiary deposits are contemporaneous fragments of the more extensive strata of the adjacent low countries.'* Since then the disturbing

*On the Formation of Valleys by Elevation.' Geol. Trans. vol. ii. 2d ser. p. 127.

force

force continued unimpaired even subsequently to the formation of some tertiary deposits, those geologists who contend it is now in the wane must reason from a very limited number of facts indeed.

Both Mr. Poulett Scrope* and Dr. Daubenyt in their recent publications agree in considering that the effects produced at present by earthquakes and volcanos are at least analogous in kind, if inferior in degree, to those that have resulted from similar agents at remote æras. More than 170 volcanos are at present in activity on the land, even if separate orifices at a short distance from one another be reckoned as one volcano; and there is reason to believe that there are at least as many, and probably a much greater number, beneath the sea-the power of which latter in throwing up islands and altering the bed of the sea is well known.

The chain of extinct volcanos described by the above mentioned authors in Auvergne, the latest of which became extinct before the period of any historical records; the streams of lava, which can be traced from their craters to the choked up vallies, and to the ancient courses of rivers thereby diverted into new channels ;these and many more phenomena raise the strongest presumption in favour of the great antiquity of some parts of the European continent. When we consider the deltas of large rivers, the strata at the bottom of freshwater lakes in Germany, Italy, and England, but, above all, the recent deposits at the bottom of the great American lakes Superior and Huron, inclosing shells of the very species now inhabiting those lakes and exposed to view in consequence of the subsidence of the water occasioned by the partial destruction of their barriers, we can affirm with certainty that modern freshwater deposits, of no inconsiderable thickness, far exceed in area the ancient freshwater formations, at present described. As to the scale on which submarine strata are now formed, we remain, of course, in comparative ignorance, but it is certainly more considerable than has been supposed by many. Whether the coral reefs of the East Indian archipelago are built up from an unfathomablé ́depth, as Flinders imagined, or are based on submarine volcanos, as Kotzebue and more modern writers suppose, we are at least certain, from the manner in which these zoophytes increase, and from the necessary accumulation of their broken fragments, that those aggregations of calcareous matter cannot be of slight depth, while we know that their superficial extent is immense. Captain King, in his late survey of Australia, sailed along a continued

Considerations on Volcanos, by G. Poulett Scrope, Esq. London. 1825.

† See p. 2. Description of active and extinct Volcanos, by Charles Daubeny, M. D. London. 1826.

+ Letters to Professor Jameson, on the Volcanos of Auvergne, by Charles Daubeny, M.D. F. R. S.

§ Dr. Bigsby in the Journal of Science, &c. No. 37. pp. 262, 263.

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us, but we shall treat of them only when they happen to throw light on the chief subject-matter of this Article. When controverted questions of interest present themselves, or generally received opinions chance to clash with our own, we shall discuss their merits without staying to inquire how far our digressions may sometimes be inconsistent with the Horatian maxim,—' sit quodvis simplex duntaxat et unum.’

A very limited number of Mammiferous quadrupeds are natives of the British islands, or have inhabited them since we have any traditionary information. If we include the Bear, Wolf, and Beaver, now exterminated, and the Fallow Deer, which is supposed not to be indigenous, they may be comprised within twenty-three genera. But we have now discovered that this part of the earth was once peopled by many other animals of the same class. The horns of the Scandinavian,* and almost entire skeletons of the Irish elk, (the latter a species now unknown throughout the globe,) have been found buried in peat and marl, evidently of origin posterior to the last extensive revolution which modified the surface of the land. Besides these, in superficial loam and gravel, consisting of transported materials, and in caves and fissures of rocks, the remains of species belonging to at least fifteen distinct genera occur; some of them identical with those still surviving in England, others being extinct species. Of these last, the remains of the Elephant, Rhinoceros, and Hippopotamus are very extensively distributed. Those of the Cave-bear and Cave-hyæna have been found in but a very few spots; but the bones of the hyæna already obtained must have belonged to several hundred individuals. Remains of a Tiger and two species of Deer have been also found, but too inconsiderable in number to enable us at present to decide on their specific characters. In similar geological situations in other parts of Europe, where the existing viviparous quadrupeds do not greatly out-number those of England, there are found in company with the fossils above enumerated a species of mastodon, (a lost genus that bore some affinity to the elephant,) a small hippopotamus, three species of rhinoceros, a gigantic tapir, a camel,† and several others. But we have not yet penetrated beyond the first boundaries of this new region of discovery. Even since the very recent publication of the third edition of M. Cuvier's Fossil Osteology, in which all the above were described, no less than thirty species of animals have been found in volcanic tufa in the department of

Edinburgh Journal of Science, vol. v. p. 129.

+ Discovered near Montpelier by M. Marcel de Serres. Mém. de la Soc. Linn. de Paris. 1825.

Puy

Puy-de-Dôme in France,* principally in Mount Perrier near the Issoire, and a large proportion of these prove to be extinct and hitherto unknown quadrupeds. Among them are an Elephant, a small Mastodon, a Rhinoceros, Hippopotamus, small Tapir, many of the genus Cervus, two Bears, three Panthers, an Hyæna, a Fox, and an Otter. We shall not at present extend our views to North America, a field rich in the same class of fossil remains, belonging chiefly (like those in the alluvial deposits of Europe) to existing genera, and also to such as are in a great degree confined at present to equinoctial regions.

We have spoken of extinct animals, because it is now admitted by all naturalists that the animals of our own acquaintance are not mere varieties of fossil species gradually changed by climate and other local circumstances,† and that the probability is extremely remote of discovering even a small proportion of the supposed extinct quadrupeds in a living state in regions hitherto unexplored. Surprizing as the above facts may appear, there are others relating to the same department of the animal kingdom, which attest far greater changes in the form of the land and the ancient character of its inhabitants. At a yet earlier epoch that part of the globe where the continent of Europe now extends, was peopled with a race of terrestrial quadrupeds of an entirely different description; a race, of which most of the genera and all the species known to us in fossil remains have been since annihilated. Their skeletons are found entombed in strata evidently deposited in the estuaries of rivers, and at the bottom of freshwater lakes, in a manner closely analogous to strata at present in the course of formation in our own lakes and rivers. In these last the remains of quadrupeds, as of oxen, beavers, and some more, are also found buried in considerable abundance, together with freshwater shells, and aquatic plants, sometimes corresponding generically with those which characterize ancient freshwater formations. The lost race of mammiferous quadrupeds above alluded to has been found in the neighbourhood of Paris, Aix, and Orleans, in Berri and Auvergne, in several parts of the South of France, and in Alsace. These remains are particularly distinguished by the abundance of genera belonging to a division of the order Pachydermata, which has now only three living representatives in the globe-the Tapir of South America, the Tapir of Sumatra, and the Daman of the Cape-whereas nearly forty fossil species of it are already ascertained. Among them are more than ten species of Palæotherium, a genus resembling the Tapir and also in some particulars the Rhinoceros :

* Ferrussac, tom. v. sec. ii. p. 436. and also No. 3, March, 1826, p. 366. + Cuvier, Discours sur les Rev., &c. p. 117. 1825.

+ Ib. p. 64.

the

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