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ART. IX.-Transactions of the Geological Society of London. Vol. i. 2d Series. London. 1824.
THAT the speculations in geology are peculiarly vague and unsatisfactory-the observations uncertain-and the deductions inconclusive-these appear to be notions not yet quite out of fashion, although the number of facts and discoveries established by this science during an exceedingly brief period of time, are perhaps unprecedented in the whole history of physical inquiry. Il n'est pas de science plus avide de faits que l'économie politique,' observed Talleyrand;* and geologists have long felt the necessity of applying similar language to their own pursuit. But, in truth, to estimate fairly the value of the results already obtained by geological research, is as yet scarcely possible; so much are we lost in the contemplation of that wide range of subjects, concerning which curiosity has been for the first time awakened, and ignorance made apparent. As we advance, new prospects open to the eye at every step, and the imagination is often so busily engaged in anticipating future conquests, that those already achieved are very apt to be forgotten.
Persons not immediately employed in these investigations hear only of conflicting hypotheses and disputed facts; of the questions, for instance, whether certain rocks are of igneous or aqueous origin-whether contemporaneous with the associated strata, or subsequently intruded-whether certain formations or groups of strata are co-extensive with the surface of the globe-whether the earth's temperature has diminished-and various others equally difficult and hitherto undecided. But however numerous the disputable points may appear, they are insignificant when contrasted with facts and conclusions now universally conceded. That, for example, the strata composing the crust of the globe are not thrown together in inexplicable confusion, but arranged in a regular order of superposition; that this order is never inverted; that the greater part, whatever be their present elevation, were once deposited at the bottom of the sea; that they have been subject, at different, and often distant, epochs, to violent convulsions; that their dislocation and contortions are most remarkable in the neighbourhood of great mountain chains; that certain series of strata are continuous over extensive districts, and often characterized throughout by peculiar assemblages of organic remains; that in the very oldest rocks no impressions of plants or animals have been discovered; that such organized bodies as occur in ancient strata differ most widely from those at present
* Mémoire sur les Relations Commerciales, &c. p. 5. 1797.
known to enjoy life; that as we ascend in the series, from the lowest towards more recent deposits, an approximation may be traced in the characters of the fossil species to those of the species now in life; that many classes of these fossil remains are so perfect and entire that their nature can be accurately determined by naturalists; that fossil plants and animals abound in high latitudes belonging to families and genera now confined to tropical climates; -these and a multitude of other discoveries are no longer contested, and are all well worthy of admiration;-some for their practical utility; others for the refutation of popular errors and ancient theoretical fallacies,-all for the new insight they afford into that grand and boundless scheme of nature, in the midst of which the human race are placed.
The first investigators of the mineral structure of the earth directed their chief attention to the primary rocks, for these are fertile in metallic riches, and may be studied in mountainous districts without the aid of artificial excavation. But the spirit of inquiry kindled by Werner and his scholars in Upper Saxony soon extended to the banks of the Seine, and here at home descended from the Pentland Hills and the Grampians, where it had engaged the powerful minds of Hutton and Playfair, to the naturalists of our southern plains, Geology, thus transplanted into a new soil, immediately assumed an altered form and aspect, and in the hands of its new cultivators yielded fruit of a different and much more attractive kind. Until within the last twenty years, the secondary strata were regarded with as much indifference as the sand and pebbles of Alpine torrents, or the muddy sediment of lowland rivers. It was never suspected that they' contained the records of various and extensive revolutions in the condition of the land and ocean, as well as in the classes of organized beings with which our globe has been successively peopled. Still less was it supposed that evidence could be deduced from the same sources illustrative of the original formation and subsequent disturbances of older rocks. The examination of the volume before us has led us to the consideration of these comparatively modern strata, and its contents afford a satisfactory answer to the few cui bono philosophers, who may question in what manner geological researches can contribute to the advancement of the useful arts or the enlargement of the human mind. The real importance of geology in promoting the general interests of society certainly does not consist in a direct and immediate tendency to advance the useful arts, although we shall have opportunities of showing that it can lend its aid to these collaterally. Its chief claim to our estimation is founded on the new impulse imparted by its discoveries to minds engaged in prosecuting
various philosophical pursuits-an impulse proportioned to the novelty and magnitude of those discoveries, and the wide range of sciences with which they are connected.
When a comparison is instituted between what now is and what has been, whether with reference to the works of external nature or the history of mankind, the desire of explaining what is obscure in the past supplies an additional motive to examine a multitude of facts, within the reach of our actual observation, with more minute accuracy, and to generalize them with more comprehensive views. Geology is continually concerned in such comparisons; by prompting us to investigate in more detail both the animate and inanimate kingdoms of nature, it has enlarged these departments of study and revealed a multitude of new phenomena connected with them; but it has done more than this: it has elevated their rank and dignity, by teaching us the laws of the aggregation and distribution of simple minerals, and by requiring more comprehensive systems for the arrangement of the animal and vegetable productions of the earth. This latter branch of science has engaged the energies of many powerful minds from the days of Linnæus to our own times; M. Cuvier, in his preface to the Règne Animal,' justly remarks that the habit necessarily derived from the study of natural history, of classing in the mind a great number of ideas, is one of the advantages of this science, the least talked of, but which may rank perhaps as the principal when it shall have been generally introduced into ordinary education.' In addition to these advantages, derived from the study of natural history, geology has the merit of exerting continually the reasoning faculties in deducing conclusions from numerous data and complicated phenomena; and although it cannot appeal to demonstrative proof, it may often conduct us to moral certainty. It is constantly concerned in weighing a great mass of probable evidence, and is therefore powerfully instrumental in exercising the mind and strengthening the judg
It is now our intention to take a rapid view of some of the principal accessions to our knowledge derived from the geological investigations of the few last years; but we shall chiefly confine ourselves for the present to the consideration of Fossil Organic Remains. We are aware that other branches of geology, intimately connected with chemistry, and exerting a more decided influence on the general process of physical science, may lay claim to higher rank, but we select a department abounding in recent and splendid discoveries, and which has till very lately been treated with unaccountable neglect. We shall have occasion to advert to most of the memoirs in the volume before
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-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.