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claim the investigation of problems concerning the creation or concentration of the matter of the globe, or the establishment of the laws of the universe. To know the successive changes which the globe has undergone, and thus to trace a retrospective outline of its successive conditions, is actually attempted by geology; but the very processes employed in this enterprise are founded on the recognition of the existing laws of nature, and altogether exclude the popular notion of a chaos, and the phi
, losophical hypotheses of a solid globe, condensing from an atmospheric expansion.”
Undoubtedly the progress of legitimate geology teaches us that the same laws of nature have operated on this globe under very
different circumstances, as to temperature, relation of land and sea, animal and vegetable life, and many other things, and it is become a proper problem for geology to discover these circumstances. In this point of view, the refiections of Leibnitz and the mathematical labours of La Place and the astronomers, become of great value, since they help to fix conspicuous landmarks for the guidance of the surveyors in this large field of science; but let no one delude himself with the notion of discovering by geological processes the emergence of the harmoniously-adjusted terraqueous globe from a former state of chaos. It is certainly not a philosophical, and surely cannot be thought a religious notion, that man shall ever discover, among the works of God, the traces of a period when his divine attributes were first awakened to rescue his creation from anarchy. Geology takes for granted the existence and collection of the matter of the globe, with its supernatant ocean and its enveloping atmosphere. Except in the degree of influence which circumstances permit them to exert, it takes for granted the uniformity of action of all material causes. The investigation of miracles never can be admitted into natural science." (Professor Phillips, Art. Geology, Encyclop. Metropol.)
Accordingly we regard Dr. Buckland's account of the original state of the globe, and of the solidification of its surface by radiation, oxidation, &c., brief and general as it is, as positively mischievous in an elementary work, intended for instruction to persons not conversant with philosophical reasoning, because it tends to give them erroneous notions as to the proper objects and limits of the science.
Dr. Buckland has obviously aimed at making his work popularly attractive, but he has done so at the expense of making it beneficial. No one totally ignorant of geology could acquire any connected outline of information on the subject, from his volumes alone. We think he judged rightly, in omitting purely mineralogical details, and in referring his readers to other works for that information; but, by altogether passing over the investigation of the modes in which existing agencies are ceaselessly engaged in removing and renewing the inequalities of the earth’s surface, in transporting to the ocean, by means of running water, the materials for new strata, analogous in their characters to those which now constitute the stratified crust of the globe, and by avoiding discussion on the probable action of subterranean forces in modifying these and former deposits,—he has voluntarily renounced a fertile source of interest and instruction, no wise inferior to that which he has explored. It is true, that accounts of the discoveries of pre-existing organized beings, differing
in form from those now inhabiting the globe, and of the series of inductions by which anatomists are enabled to read the history of an extinct species in a small portion of its relics, may appear more captivating than dry details of mere chemical and mechanical actions ceaselessly modifying the surface of our planet. But the two classes of phenomena are too intimately connected with its history, to allow of the one being correctly treated independently of the other; and an author of Dr. Buckland's rank and authority should rather have directed his readers in the right path to knowledge, than have humoured an idle taste for what was especially amusing. The existence of this taste being strongest in least cultivated minds, it becomes the imperative duty of a teacher to control it by strict mental discipline; unfortunately the necessity for making the acquisition of knowledge pleasing, induces a constant violation of this rule; and popular works on scientific subjects are too often calculated to convey erroneous notions on the precise limits between what is really ascertained as fact, and what is the result of speculative induction. Works on geology are peculiarly liable to this defect, from the nature and variety of the subjects they treat of; and yet no science has really less need for such extrinsic aid; the number and singularity of the facts which it develops are quite sufficient to invite a study of them by any one capable of appreciating the beauty of an extensive and connected chain of evidence, diligently accumulated and cautiously examined.
If it be alleged that the primary purport of the publication was to teach natural theology, and not the history of the earth, and therefore, that portion of the latter was most dwelt on which furnished the greatest number of arguments bearing on the principal object *, -we reply, that the value of any argument adduced from a physical science must depend on the reader's conviction of the authenticity of the facts on which it is based, and of the soundness and consecutiveness of the deductions made from them; to enable a reader, consequently, to judge for himself, he ought to have a complete general outline at least of the science laid before him; this plan having been successfully adopted by Messrs. Whewell, Kidd, Drs. Roget and Prout, Dr. Buckland might have followed such examples without derogation, and with more probability of making his work efficient. This mode of proceeding is the more necessary in the present case, because most persons are capable of following the train of reasoning by which the principal conclusions in geology are arrived at, supposing the facts to be authentic, and these the general reader must take on the authority of his author, whatever the subject may be he is studying.
Nor are the evidences of design and adaptation in the details of the organic creation, more convincing proofs of the existence of an eternal, intelligent, and omnipotent First Cause, than is the constancy of the laws by which inorganic matter is governed. The deductions of geology, as we have seen, are based on the assumption of this constancy, and astronomy has established the fact regarding the all-pervading laws of gravitation. If, then, the science we are considering can be shown to afford analogous presumptive proofs regarding others, the argument would be interesting and important enough to deserve more extended notice than Dr. Buckland has bestowed on it. One of the most striking, because novel, facts mentioned in his work is the discovery of the eyes of extinct crustacea, which by their resemblance to those organs in living races, indicate the identity of the light of the primæval world with that element which now pervades space. Geology offers numberless other conclusions of an analagous kind with respect to inorganic creation: fossil plants, by their similarity in structure and developement to existing species, may be fairly concluded to have been nourished by water and air of the same chemical, as well as mechanical, properties as that which fills our seas, rivers, and lakes, and descends from the clouds in rain and dew. The arrangement of the component ingredients of conglomerates and breccias reciprocally establish the permanence of their specific gravity, and of the hydrostatic pressure of the water which floated them to their present sites; and as the gravitation has been shown to be constant, the other laws, chemical and mechanical, may be inferred to be so likewise. These presumptive proofs being established, the nature of the evidence on which geological deductions rest becomes of more weight.
* When a variety of examples only selves. Dr. Buckland has repeated the concur to the establishment of the accuracy conclusion, that design is to be inferred of one line of argument, it is sufficient to from the evidence of adaptation to an end, develop that argument once, in all its so frequently, and so nearly in the same generality, and to leave the individual in- terms, as to be irksome, if not positively stances of its application to speak for them- / ludicrous.
Having fulfilled the least agreeable part of our duty, we may now indulge in the pleasure of pointing out a few of the many beautiful illustrations and philosophical deductions, which the reader will find in Dr. Buckland's work, expressed with that force and grace which make both his writings and lectures so popular. We would especially call attention to the following passage, as inculcating a principle in which man is but too much deficient-humility, and which ought to have double force as coming from a philosopher and a divine.
" I would in this, as in all other cases, be unwilling to press the theory of relation to the human race so far, as to contend that all the great geological phenomena we have been considering were conducted solely and exclusively with a view to the benefit of man. We may rather count the advantages he derives from them as incidental and residuary consequences; which, although they may not have formed the exclusive object of creation, were all foreseen and comprehended in the plans of the great Architect of the globe, which in His appointed time was destined to become the scene of human habitation.
“With respect to the animal kingdom, we acknowledge with gratitude that
among the higher classes there is a certain number of living species which are indispensable to the supply of human food and raiment, and to the aid of civilized man in his various labours and occupations; and that these are endowed with dispositions and faculties which adapt them in a peculiar degree for domestication: but their number bears an extremely small proportion to the total amount of existing species; and with regard to the lower classes of animals, there are but very few, among their almost countless multitudes, that minister either to the wants or luxuries of the human race. Even could it be proved, that all existing species are serviceable to man, no such inference could be drawn with respect to those numerous extinct animals which geology shows to have ceased to live long before our race appeared upon the earth. It is surely more consistent
with sound philosophy, and with all the information that is vouchsafed to us respecting the attributes of the Deity, to consider each animal as having been created, first for its own sake, to receive its portion of that enjoyment which the Universal Parent is pleased to impart to each creature that has life; and secondly, to bear its share in the maintenance of the general system of co-ordinate relations, whereby all families of living beings are reciprocally subservient to the use and benefit of one another. Under this head only can we include their relations to man, forming, as he does, but a small, although it be the most noble and exalted part, of that vast system of universal life with which it hath pleased the Creator to animate the surface of the globe.” (Vol. i. p. 101.)
One very striking and satisfactory result of the investigations of extinct races of animals, is the discovery of those links in the great chain of organized beings which were wanting to its continuity. We possessed long detached segments of this chain, but we searched in vain among living genera for these connecting portions; geology is now come to the aid of natural history, and from the numerous contributions it has already furnished, we may hope it will in time enable us to complete what is still deficient, and establish the truth of the dictum, Natura non facit saltus.
The order Pachydermata, as our readers are aware, was particularly deficient in genera to constitute intermediate links between such remotely allied animals as the horse, hog, rhinoceros, hippopotamus, tapir, and elephant; the numerous extinct genera of this order, already discovered, fill ир
“This numerical preponderance of pachydermata, among the earliest fossil mammalia, beyond the proportion they bear among existing quadrupeds, is a remarkable fact, much insisted on by Cuvier; because it supplies, from the relics of a former world, many intermediate forms which do not occur in the present distribution of that important order. As the living genera of Pachydermata are more widely separated from one another than those of any other order of mammalia, it is important to fill these vacant intervals with the fossil genera of a former state of the earth; thus supplying links that appeared deficient in the grand continuous chain which connects all past and present forms of organic life, as parts of one great system of creation.” (Vol. i. p.
88.) Besides filling up the gaps in the order, some of the fossil genera
of Pachydermata form points of connexion between that and the orders Ruminantia and Edentata, and one, the Dinotherium, cannot properly be assigned to any one of these orders exclusively, on account of the singular anomalous formation of its lower jaw, terminating in two tusks projecting downwards, like those from the upper jaw of a walrus.
Most of those species which belong to extinct genera agree in some points with several widely dissimilar living species, which are by this means brought into closer union,--and not only orders, but even classes, are placed in unexpected affinity by means of these inhabitants of a primæval world.
The Saurian Reptiles and Fishes are connected by the gigantic Ichthyosaurians; but a still more marvellous example of the union of characters of remote classes is presented by that mystery, the Pterodactyli, which were intermediate to the Saurians and the Cheiroptera.
The wonderful and imposing fact of the successive creation and extinction of species is brought before the mind with peculiar force, when we absolutely find the relics of an extinct order still lingering, as it were, on the globe, and perhaps destined at no distant period to die out like their ancestral family. We may fancy the Polypteri of the African, and the Lepidostei of the American rivers, viewing with indifference a creation in which they feel themselves out of their places, and recalling those periods of Ichthyal grandeur, when the aristocratic supremacy of Megalichthys was acknowledged throughout the deep, and the lordly Sauroids were legitimate monarchs by the strength of their teeth. We doubt not the Bichir of the Nile often views the crocodile with envy, and repines, like other creatures, at the partiality of Providence, which has shown such favour to a modern branch of their noble stock, while the true representative is struggling with adversity, and only holds the precarious tenure of its existence by the compassionate forbearance of such plebeian upstarts.
It would be a curious and interesting object of inquiry to find whether, in the present state of our knowledge of the relations between organic life and the inanimate world, we possess any data for venturing at a guess what existing species among the higher orders will next become extinct, in obedience to this law of succession, which seems to form a part of the code of Creation; and to trace the probable effect of human agency in modifying the natural progress of this event,—whether there exists a generic power of continuance in certain races which will effectually counteract the unremitting persecution and war of extermination carried on against them, in consequence either of the real wants, the cupidity, or the cruelty of mankind. It is most probable, however, that we have but little influence beyond keeping down the numbers of certain genera or races, and that it is only because the accurate adjustment between the organic functions and the external world is deranged, that a race of animals becomes extinct. If it be true that in the Dodo we have an instance of a genus becoming extinct since the creation of the human race, how much must we regret that we possess such
information of the circumstances.
The incorrectness of the conclusion, which had been hastily adopted from insufficient geological researches, that there had been a progressive advance from the simpler to the more complicated forms of organic structure, has been established by different and conclusive arguments, suggested by more accurate knowledge. The avowal, that we know not what class of animals are to be considered as a standard for estimating relative simplicity or complexity of structure, is extorted from us by Ehrenberg's investigations of Infusoriæ; while the discovery of types of the higher classes, as we term them, in the more ancient strata, prove that at all periods there has existed a proportional variety among cotemporary species, as at present. In the following passage we have laid
open to us a new source of error to be guarded against, in our attempts to interpret the state of organic creation in remote eras.
“ The values to be attached to numerical proportions of fossil plants, in estimating the entire condition of the Flora of these early periods, has been diminished by the result of a recent interesting experiment made by