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braces the history of our globe as well as its actual composition; it endeavours to trace the succession of events which have preceded its present state; to ascertain not only the changes which have taken place, but the causes, or, in other words, the physical connexion of those changes, and to determine the order, the time, and the circumstances under which they were effected.

The province of the geologist resembles therefore in some respects that of the historian. He must diligently examine ancient documents, he must estimate the degree of credibility that is due to them, he must compare their report with the evidence of actual appearances, and must not even neglect, in the absence of direct proof, the feeble and uncertain aid of oral tradition. His conclusions concerning remote antiquity will even then amount to probability only, or, at the utmost, to what is called moral certainty; and they will always lie open to correction and progressive improvement, in proportion as new information may be obtained, without calling upon us to reject, as altogether false and unworthy of belief the testimony which had been before employed; and without reflecting discredit or contempt upon former reasonings.

It is in a great measure owing to this mixed character, that so much discord has prevailed in the schools of geology. Possessed as we are of a brief historical account of the creation and the destruction of the habitable globe, an account which the most civilized nations receive as of divine authority, and which all learned men admit to be the most ancient record in existence, it has been the exclusive object of one class of inquirers to comment, as it were, upon that text, and to explain the manner in which all the phenomena we discover may have been produced by the operations there recorded. Others, on the contrary, rejecting this evidence altogether, have confined themselves to the examination of natural phenomena, and applying to these facts the laws of nature as far as they are understood, have boldly maintained opinions respecting the history of the globe, wholly incompatible with the truth of that volume in whatever way interpreted.

To say nothing here of those exploded cosmogonies, the dreams of pious and ingenious men, who, without investigation of the component parts of the earth, spun theories out of their own brain, it will be sufficient to mention, as a specimen, one of the latest and by far the most respectable of the first class, Catcott. In his treatise on the Deluge there is evidence of a strong spirit of inquiry, much knowledge in detail, and considerable sagacity in combining and reasoning upon the minute circumstances, which prove the universal action of the deluge upon the surface of the earth. He too was not ignorant of the vast store of organic sub

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stances deeply imbedded even in the hardest strata; of the successive depositions of these strata, and the various forms of animal life which they exhibit. Yet chained to his hypothesis, that all these phenomena are the effects of that single catastrophe, he is driven to adopt the absurd conclusion, that the whole crust of the globe was then dissolved into a soft pulp, which gradually hardened again and inclosed those remains in the several strata as they happened to be dispersed through the waters of the deluge; not offering a syllable to explain how the same process, which, according to him, reduced the solid rocks and even metallic instruments to a fluid, yet spared not only bones and teeth, but all the myriads of animal exuviæ preserved as we find them even in their finest and most delicate forms.

The natural consequence of these abortive attempts of the friends of religion was to encourage desertion into the ranks of the enemy. Disgusted by such preposterous reasoning, and convinced of its falsehood, men rushed, as is too common, into the opposite error. It soon became the fashion to doubt the truth of the Mosaic history of the deluge, and Linnæus even ventured to declare that he saw no evidence of such an event in the present state of the earth. Philosophers of the French school had long treated it as a fable: and in our own country a system was broached about thirty years ago, under the name of Dr. Hutton, which professed to explain the actual condition as well as the past history of our planet, without reference to any beginning of things, or any supernatural interposition in the changes which have taken place. With the aid of two modest postulates, one, an eternity of organized matter a parte ante, the other, a magazine of fire within the shell of the earth, all the revolutions of our globe were accounted for by causes now in action. The corrosion of the atmosphere, according to the Huttonian system, is incessantly wearing away the summits and sides of hills and mountains; the matter thus detached is carried down by streams to the vallies, and by the larger rivers to the sea, where it is spread out into strata formed gradually on the bed of the ocean. After this process has been continued for thousands or perhaps millions of years, and a good portion of the existing inequalities on the earth's surface has been destroyed, an expansive force is supposed to act from beneath, and to heave up these submarine strata already hardened by the central fire, forming on a sudden new continents with their hills and vallies, which are again to be subjected to disintegration by the atmosphere, again to be submerged in the ocean by the conveyance of rivers, and to form the materials of future continents in endless succession.

*Catcott on the Deluge, p. 272.

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That a theory so extravagant, so gratuitous, so utterly unsupported by fact or by testimony should have been allowed even an indulgent hearing in a philosophical age, was hardly to be expected. That it should have had what is called a run, that it' should have been illustrated and defended by a man of science,, a professed admirer of the Baconian method of inquiry, and one of the ablest writers of his day, is to be reckoned among, those anomalies of human nature which, according to the humour we are in, provoke either our regret, our indignation or our contempt. Professor Playfair recommended it for its originality, grandeur and simplicity;' and he enlarged upon the powerful agency of the sea as co-operating with the rivers, in the work of reducing the inequalities of the earth.

We must be allowed here to remark that the very terms of the panegyric indicate a remarkable confusion of thought, when applied to a system of philosophy, and a total forgetfulness of that character which, as we observed in the opening of this article, belongs to the department of geology not less than to that of history. In discussing the merits of an invention in the arts of life, or of any new method or plan, its originality, its simplicity or its grandeur may indeed be proper objects of consideration, and a fair ground of praise. But when the inquiry is concerning a matter of fact, when we have to demonstrate, not to invent; to inquire what has been, not to speculate on what may be, the introduction of these ideas is manifestly improper, and has a tendency to mislead and confound us. It is precisely that error against which the great founder of modern philosophy cautions his reader. The true and only object of philosophy is the interpretation of nature. We must take nature as we find her, and dismiss from our thoughts the vain desire of modelling her according to any pre-conceived fancy of our own.

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In the miserably meagre collection of facts also upon which this fabric was raised, and in the sudden flight to the first principles of things, after a superficial examination of a few phenomena, we see a marvellous neglect of that code of inductive reasoning which Bacon delivered, and which is continually quoted as an oracle by that very school from which this theory sprung. There is something so remarkable in all this, and at the same time so illustrative of the main subject to which we are soon to proceed, that we shall not scruple to burden our pages with an extract by way of specimen.

'On observing the Patowmack,' says Mr. Plairfair, where it pene trates the ridge of the Allegany mountains, or the Irtish, as it issues from the defiles of the Aitai, there is no man, however little addicted to geological speculations, who does not immediately acknowledge, that

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the mountain was once continued quite across the space in which the river now flows: and if he ventures to reason concerning the cause of so wonderful a change, he ascribes it to some great convulsion of nature, which has torn the mountain asunder, and opened a passage for the waters. It is only the philosopher, who has deeply meditated on the effects which action long continued is able to produce, and on the simplicity of the means which nature employs in all her operations, who sees in this nothing but the gradual working of a stream, that once Aowed as high as the top of the ridge which it now so deeply intersects, and has cut its course through the rock in the same way, and almost with the same instrument, by which the lapidary divides a block of marble or granite.'-Illustrations of the Huttonian Theory, § 102.

Statements such as these seem hardly to be entitled to a serious answer. To assume an infinite series of centuries merely that weather may have time to remove mountains and plant them in the sea, and that water may cut through the ridge of a mountainous chain, (a thing to the performance of which in all eternity it could never tend to approximate,) is too monstrous an outrage upon common sense to be treated without ridicule. Nothing but scepticism could venture to make so large a demand upon human credulity-and all for the purpose of drawing away the mind from the contemplation of any beginning of things, and of teaching that there is no occasion (to use Dr. Hutton's own words) 'for having recourse to any destructive accident in nature, or the agency of any preternatural cause, in explaining ' that which actually appears.'

Notwithstanding this, an ample, a candid, and a respectful examination of the theory was laid before the public by De Luc, a philosopher of whom it is impossible to speak without bearing testimony to the amiable qualities of his heart, as well as to the great services he has rendered to the cause of science. That he had strong prepossessions in favour of revealed religion is not denied; but they have warped his reasonings on physical facts much less than the opposite prepossessions appear to have affected his opponents. This however is not enough to say on such a subject. We contend therefore boldly, that in an inquiry into the history of the world, to reject the evidence of written records, as wholly irrelevant and undeserving of attention, is in itself illogical and unphilosophical. It is true, that to assume these records to be infallible, and above all criticism, is to prejudge the question, and to supersede all inquiry: but when the case is one of a remote age, and full of difficulty, when we are compelled to compass sea and land for presumptive and circumstantial evidence, to turn a deaf ear to that volume which professes to give a direct and detailed narrative of the whole transaction, is a greater violation of the laws of sound reasoning, and is a symptom of stronger prejudice

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against religion, than all the annals of superstition and bigotry can furnish against true philosophy.

De Luc entered upon his task with an active and persevering spirit. He patiently analysed his opponent's argument, exposed his sophistries, his inconsistencies, and his gratuitous assumptions, and by a large induction of facts, collected chiefly from personal examination, he overthrew the fundamental position upon which the Huttonian theory rested; proving that those processes of nature by which its abettors accounted for the conversion of old continents into new ones, in the course of millions of years, could not by any possibility effect what was pretended, for that in fact they had a direct tendency the other way. All the operations produced on them, says De Luc, (and no man was better entitled to speak from accurate and extensive observation,) by the combined action of atmospherical causes, gravity, and running waters, have tended only to obliterate their original characters, by reducing the abrupt faces into gradual slopes, by softening down the asperities of the hills, by raising instead of excavating the beds of vallies, and by filling up the cavities of lakes; while neither the materials conveyed by rivers to the sea, nor those detached from the steep coasts by waves are transported to any distance: the waves and the tides throw them back upon the coasts, and even bring up the sand from the bottom, wherever they can reach it. § 290.

We dwell the longer upon the works of this excellent and candid writer, because although he has fallen into some material errors, yet we regard his writings as constituting a kind of epoch in geological science. He first, if we mistake not, hit upon that sound distinction which has introduced a ray of light into this confused and intricate subject; by the aid of which the inquiry has been since pursued with rapidly increasing success. He divided the various phenomena which the surface of the earth exhibits, into those which are produced by causes still in action, and those whose causes have ceased to act. Adopting this distinction, and proceeding to examine with indefatigable industry, the phenomena of coasts, vallies, lakes, ravines, estuaries and deltas, he arrived at similar conclusions in every case, by processes totally independent of each other; and these conclusions were in strict accordance with the scriptural account of an universal deluge, which overwhelmed the earth about four or five thousand years ago.

De Luc indeed frequently talks of the birth of the present continents, as if their forms must needs have been the result of a single catastrophe; and his favourite hypothesis, which he is ever labouring to support, is, that the deluge was effected by the sinking of the old continents, when the sea rushing into the lower

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