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numerous in this our island, although it is still as true as it was in the time of Trinculo, that if a strange beast' be exhibited here, • there is not a holyday fool but would give a piece of silver.' Whether it be a giant or a dwarf, a natural or artificial deformity, a Chinese mermaid, or any creature born with more or less than its due proportion of members, it will not want admirers of a certain class. But there is also no country where so many persons can be found of inquiring mind and liberal education, and yet almost entirely ignorant even of the first elementary steps of natural history. If these are without skill in comparative anatomy, and are yet interested in the results of these osteological researches, we may remind them that a leaning on the side of credulity was deemed truly philosophical by Pliny-nam mihi contuenti se persuasit Rerum Natura nihil incredibile existimare de eâ.'* · If any thing could justify,' says Cuvier,' those hydras and other monsters whose figures are so often repeated in the monuments of the middle ages, it would incontestably be the Plesiosaurus.'+ Yet we may confidently say of this creature, and of the Megalosaurus and Iguanodon, what Ariosto had the audacity to declare of his hyppo-griffin :
• Non finzion d'incanto come il resto
Ma vero e natural si vedea questo.' The Pterodactyls, however, or flying lizards, described by Cuvier, I recal still more forcibly to our recollection the winged dragons of fabulous legends. They might, perhaps, have been as inoffensive as the small flying reptile now found in Asia and Africa ;S but the size of some of them, their long jaws armed with sharp teeth, and the hooked nails of their claws, would render them truly terrific were they to revisit Christendom, now no longer under the shield of the Seven Champions. That we should find some fictitious animals of romance nearly realized, upon being suddenly admitted as it were to the creations of new worlds, will surprize none who are conversant with the laws of organic nature, and who have well considered the principles on which the charms of poetic fiction depend. In fabricating imaginary animals the license of fiction does not extend to extravagant violations of known analogies, but merely to the combination of parts and functions never yet seen to co-exist. It is not long since naturalists discovered in a living animal, the Ornithorhynchus of New Holland, the organization and habits not
Pliny, lib. xi. chap. 3.
Cuv. Oss. Fos. vol. ii. part ii. p. 358. 380.
only only of different genera, but of three distinct classes of former systems, all united and blended together in one single individual,
To enter at large into the consideration of other classes of organic remains, or to examine in detail those described in the present volume, would be inconsistent with our present limits and scope. In the illustration of these objects, lithography has been success. fully employed. This art, so strongly recommended by its surior cheapness, may exert a favourable influence on the future progress of science, and particularly on natural history, which has always been retarded by the unavoidable expense of engraving. The plates descriptive of the osteological structure of the large Reptiles we have been mentioning deserve especial commendation, as do the figures of plants discovered by Mr. Mantell in the same strata with the Iguanodon, near Cuckfield in Susses. These remains consist partly of ferns, that numerous fossil genus, and partly of vegetables analogous to the genera Zamia and Cycas, now particularly characteristic of tropical regions. The plates of Orthoceræ* from the islands of Lake Huron are also admirably executed in lithography. These chambered univalve shells, so interesting to the conchologist from the peculiar structure of the siphuncle, are described in a paper by Dr. Bigsby on the geology of part of North America bordering on Lake Huron. No recent species of Orthocera hitherto discovered exceeds half an inch in length; the fossil species both in Europe and America frequently attain the length of many feet. The only multilocular univalve Testacea of large dimensions now existing are some species of Nautilus, and these are confined to tropical climates. The abundance therefore of Ammonites, Orthoceræ, and Nautili of great magnitude, in the strata of Europe and North America, is worthy of observation, as tending, in concurrence with other branches of organic remains, to confirm that striking deduction of geology, that the former temperature of the northern hemisphere was much higher than it is at present.
As the fossil species appear to be all, with very few exceptions, extinct, we reason only from analogy when we draw this conclusion, and we ought therefore to require a great accumulation of evidence, together with perfect harmony in the proofs. This question, concerning the former temperature of the globe, is extremely interesting, and it has so often been alluded to during our consideration of fossil animals and plants, that we shall lay before
However great may be the expedience of a speedy reform in the nomenclature of natural history, we must not attempt it in this place. It may be as well, in compassion to the uninitiateri, to inform them that, when Lamarck writes Orthocera, he means Orthoceras, and that, in tire language now spoken by conchologists, Orthoceræ stands for Orthocerata.
strata several hundred species are now described; and it appears that the same kiuds are, with few exceptions, common to Eng. land, France, and Germany. It has been conjectured that the trees of these ancient forests were swept by torrents into friths and estuaries, and there buried, sometimes unmixed with foreign matter, but often with sand or with argillaceous and calcareous sediment. The accompanying shells are generally of a fluviatile character, but sometimes (as is perfectly consistent with the hypothesis) of marine genera. : In whatever manner these strata originated, the arrangement of their materials was evidently governed by the laws of gravitation, and they must therefore have been at first nearly horizontal. By various convulsions they were subsequently thrown into an inclined and often vertical position, and at other times fractured or violently contorted; at a still later period the truncated' edges of these strata were covered, in a variety of instances, by marine deposits of great thickness, inclosing shells, zoophytes, and many gigantic reptiles before described, and plants differing almost as widely from the Flora of the coal as from existing vegetable productions. To describe the various formations occurring in England, for the most part of marine origin, all evidently more recent than the carboniferous series, would require a separate treatise. We shall merely add that their organic contents indicate successive changes in animal and vegetable life, and the study of the whole phenomena attending them has uniformly impressed the minds of naturalists with an idea that periods of great duration elapsed during their accumulation.
After so many changes in position, the result apparently of alternate elevation and subsidence, we now find a large portion of the coal measures in Great Britain at various heights above the level of the ocean—sometimes exceeding 1000 feet; but a great portion still remain beneath that level, as is demonstrated by the dip of the strata on our coast. · In consequence of the abundance and accessibility of this mineral in our islaud, and its opportune association with beds of iron ore, and the invariable contiguity of limestone, employed to flux the iron ore, we are enabled to surpass all other nations in the cheapuess of machinery. Without this advantage not only would the great superiority of our manufacturing system be impaired, but we should be incapable of availing ourselves of a great part of our metallic riches. Independently therefore of the comfort derived from an economical source of fuel for domestic purposes, we may safely affirm that, without the aid of coal, neither the population nor the commerce.or maritime power of the British empire could be maintained on their present extensive scale. If we pause for a moment and consider how intimately the
degree of moral advancement, and the comparative political power of our own and many other countries is thus shown to be connected with the former existence of a race of plants now extinct, which bore but a faint analogy to living species, and flourished at periods of immense antiquity, probably under a climate and in a state of the earth widely distinct from the present, the mind is elevated to an exalted conception of the magnificent extent of the whole system of nature, and of the wonderful relations subsisting between its remotest parts. The present disposition of the strata in the carboniferous series, and indeed in every other formation, is the best, if not the only conceivable, arrangement, by which each might be made to rise in succession to the surface, and present in its turn a variety of useful minerals or of soils adapted for different agricultural purposes. Had the strata been permitted to remain horizontal, they would have invested the nucleus of the earth, as Dr. Buckland has justly observed, in concentric coats, and the inferior must have been buried for ever beneath the highest.'* Now it scarcely admits of a doubt that the agents employed in effecting this most perfect and systematic arrangement have been earthquakes, operating with different degrees of violence and at various intervals of time during a lapse of ages. The order that now reigns has resulted therefore from causes, which have generally been considered as capable only of defacing and devastating the earth's surface, but which we thus find strong grounds for suspecting were, in the primeval state of the globe, and perhaps still are, instrumental in its perpetual renovation. The effects of these subterranean forces prove that they are governed by general laws, and that these laws have been conceived by consummate wisdom and forethought. Their consequences were formerly enumerated amongst the signs of anarchy and misrule, whence the Epicurean hypothesis originated that the earth was first formed, and has been since maintained, by Chance; and in later times they have been appealed to as the visible manifestations of God's wrath and of a penal dispensation.
After the unexpected discoveries, for which we may already thank the Science of Geology, it can no longer be matter of surprize, that we remain in ignorance of the ends answered by many of the operations of nature and of her living works, in whose form and structure such infinite variety, contrivance and beauty are displayed. The zoophytes and testacea, whose exuviæ are entombed by millions in stratified rocks, contribute to our wants and enjoyments perhaps in a far greater degree than the analogous races that now hill the great deep with life. The fossil species have
Inaugural Lecture, p. 11. Oxford. 1819.
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
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 uniforin 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 Llevation.' Geol. Trans, vol. ii. 2d ser. p. 127.