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must also be said, as corroborative of such an inference, that the laws of the radiation of heat, and those of chemical combination, do permit the needful inference that such a sphere might or must finally become a fluid ; or at least a fluid globe surrounded by an atmosphere.

"This, then, is the second presumed condition. And the evidence for such a fluid globe is found, first in its statical figure, and secondly in the various geological facts already reviewed, and founded primarily on the phenomena of volcanoes, which prove that the interior of the earth, beyond a certain depth, is at present in a fluid condition from the heat which was once sufficient for the preceding more extensive effects.*

"And here terminates that which is of most difficult investigation in the theory of the earth, and which by many will still be held with Hypotheses. The evidence, such as it is, is given ; what a rational philosophy will pronounce on it, will always deserve attention. . . .

"I know of no mode in which the surface of a fluid globe could be consolidated, but by the radiation of heat; while of the necessity of such a process I need not again speak. The immediate result of this must have been the formation of rocks on that surface: and if the interior fluid does now produce the several unstratified rocks, the first that were formed must have resembled these, if not all. We may not unsafely infer that they were granite, perceiving that sub

* An assumption not only without proof and against the laws of matter, but rejected by a large body of the most eminent geologists themselves.

stances of this character have been produced wherever the cooling appears to have been most gradual. The first apparently solid globe was therefore a globe of granite, or of those rocks which bear the nearest crystalline analogies to it."— Geology, vol. ii., pp. 416, 417.

Essentially the same views are advanced by Sir H. T. De la Beche.

But this hypothesis is altogether unphilosophical. The fusion of matter, or its existence in a gaseous form, "from the presence of intense heat" which is the necessary condition of its assuming that shape, is not a natural but an artificial state. It is the result of chemical action, and implies therefore a previous existence of the matter in a different form. The supposition that the earth was created in that state is a self-contradiction, therefore, and at war with the laws of matter. It might as well be supposed that the world was created with thunderstorms and earthquakes in progress, which imply a previous existence of the globe and atmosphere in a different state; or with animals on the point of giving birth to offspring, which implies their previous existence. Moreover, as the heat that is evolved in the action of chemical agents on each other is always previously latent in those agents, the supposition of the fusion of the matter of the globe by the presence of intense heat, implies that that heat had previously existed in the mat

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ter of the globe in a latent state; and that again implies that anterior to the development of that heat, that matter existed in a different form. It assumes also that an immeasurably greater quantity of latent heat existed in the matter of the globe in its original condition than now subsists in it; and it is implied also in the supposition, that beyond that which is now latent in the earth, a quantity as much greater as would raise the whole of the substances of the globe to the most intense fusion and convert them into gas, has passed off from it by radiation into the realms of space. But that is not only wholly gratuitous and infinitely improbable, but is in contravention of the principles of geology also, which forbid the assumption of any geological condition of the earth as a basis of induction, that cannot be proved to have actually existed; or any geological effect that cannot have resulted from the chemical and mechanical forces that are now giving birth to changes in the materials of the globe. But what can transcend the extravagance of the fancy that these forces, acting with even thousands of times their present intensity, can have held all the materials of the globe in a state of fusion; or that all the chemical agents which it contains, in any combination that is possible, are adequate to such a stupendous effect? By the supposition, caloric, the grand agent of the imagined fusion, has in a great degree radiated from the earth into space, so that it no longer exists here in the force that is requisite to that effect. A splendid combination of solecisms for the basis of a philosophical theory! A magnificent platform for a scientific confutation of the record God has given of the work of creation! How is it that these writers have overlooked a consideration so obvious, and that indicates so decisively the untenableness of their theory?

QUESTIONS.

What is the object of the discussion commenced in this chapter? Do geologists deduce their inference of the age of the world from the strata themselves, or from some theory respecting them? What is the first ground on which they found it? What is the second? What is the third? If the facts of geology are not the basis of that inference, is it not clear that those facts do not prove it? In order to sustain it, must they not prove, not merely assume or suppose the ground from which they deduce it? Will then, proving that the postulates from which it is drawn, are mere suppositions, be to confute its claim to be regarded as a truth scientifically demonstrated? Will showing that their hypotheses are irreconcilable with the facts and principles of the science, and the laws of nature, be still more effectually to overthrow it? What is the first postulate on which they found their deduction of the great age of the world? State some of the forms in which they express their belief that the forces by which the strata were constructed, were the same in kind and energy, as those which are now acting on the surface of the earth. Are they generally agreed on this point? What is their other postulate? What principal writers maintain that proposition? State the form in which Dr. Buckland expresses it. In what language is it asserted by Mr. Macculloch? How is it taught by Sir C. Lyell? How by Mr. Mantell? Are geologists generally agreed in this doctrine? Of what did the surface of the primitive earth consist, according to these writers? By what do they hold those supposed granite continents were disintegrated? By what were the particles to which it is held they were reduced, borne off to the ocean? What must geologists do, to demonstrate their theory? Must they prove that it rests on indubitable facts? Or is it enough that it rests on mere hypotheses? What then is the first objection to their theory respecting the sources from which the materials of the strata were drawn? Do not geologists attempt to prove their theory? State the language in which they present it as a supposition, or hypothesis. But if the derivation of the materials of the strata from such continents, is merely hypothetical, must not the inference that a vast series of ages was occupied in disintegrating those continents, transporting their detritus to the ocean, and forming the strata from them, be merely hypothetical also? Can an inference from a mere imagined fact, have any more reality, or be any more entitled to be considered as a demonstrated truth, than the merely imagined fact itself is? If there is no certainty that the strata were drawn from such a source, how can the supposition that they had such a derivation, prove that infinite ages were occupied in their formation? Ought not these philosophers who claim that they, alone, are competent to treat the subject scientifically, to be able to answer this question plainly and demonstratively?

What is the next objection to their theory of the formation of such granite continents? What is the language in which Dr. Buckland teaches that the world was created in the form of gas? What is the language in which Mr. Macculloch represents it as originally existing in that shape? Is this proved by them, or merely assumed or supposed? What is the first objection to it? State some other absurd supposition that is parallel to it. Does the supposition that the world was created in the form of gas, contradict itself? By implying what? What unauthorized assumption does it involve respecting the quantity of heat in the globe? Is that in contradiction to the principles of geology, as well as assumed without authority?

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