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of the atmosphere, and to the violent operations of the waters moving upon the surface of the earth, there is a more sudden destruction, that may be supposed to happen sometimes to our continents of land. In order to see this, it must be considered that the continents of our earth are only raised above the level of the sea by the expansion of matter placed below that land, and rarified in that place; we may thus consider our land as placed upon pillars, which may break, and thus restore the ancient situation of things, when this land had been originally collected at the bottom of the ocean. . . . . In that case, whatever were remaining of that land which had for millions of ages past sustained plants and animals, would again be placed at the bottom of the sea; and strata of every different species might be again deposited upon that mass, which, from an atmospheric situation, is now supposed to be lower than the surface of the sea. Such a compound mass might be again resuscitated or restored, with the new superincumbent strata, consolidated in their texture and inclined in their position. In that case the inferior mass must have undergone a double course of mineral changes and displacement; consequently the effect of subterranean heat or fusion must be more apparent in this mass, and the marks of its original formation more and more obliterated.'

Such are the hypotheses:-The next step is enquiry as to the facts:

If, in examining our land, we shall find a mass of matter which had evidently been formed originally in the ordinary manner of stratification, but which is now extremely distorted in its structure and displaced in its position; which is also extremely consolidated in its mass, and variously changed in its composition which, therefore, has the marks of its original or marine composition extremely obliterated, and many subsequent veins of melted mineral matter interjected, we should then have reason to suppose that here were masses of matter, which, though not different in their origin from those that are gradually deposited at the bottom of the ocean, have been more acted on by subterranean heat and the expanding power—that is to say, have been changed in a greater degree by the operations of the mineral region. If this conclusion shall be thought reasonable, then here is an explanation of all the peculiar appearances of the Alpine schistus masses of our land, those parts which have been erroneously considered primitive in the constitution of the earth.' And, in another place,- Appearances might thus be found, to induce natural philosophers to conclude that there were in our land primary parts, which had not the marine origin which is generally to be acknowledged in the structure of the earth; and by finding other masses of marine origin, superincumbent upon those primary mountains, they might make strange suppositions in order to explain those natural appearances.' -Pp. 373-377.

These views, it must be remembered, are very different from conjecture. They are delivered by their author as legitimate consequences of what he supposed that he had proved;—corollaries to the great propositions relating to the subterraneous agency of heat and compression. But though they had been, when proposed, no more than hypotheses; still, when we know that every day has multiplied the proofs that they are true, it

must be acknowledged they were the anticipations of a genius which bestows on its possessor almost prophetic power, and enables him to say to the ungifted objector,-I hear a voice thou canst not hear—I see a hand thou canst not see!'

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The range of mountains which traverses the south of Scotland, from Portpatrick on the west coast to St Abb's Head on the east, forms an excellent example of the strata to which Hutton gave the name of 'primary schistus.'-(the transition rocks of Werner, now referable, in part, to the Silurian and Cambrian systems.') 'There can be no doubt,' he says, 'as to the original 'formation of these strata from the detritus of former bodies. 'How far, then, does it appear, that these primary masses had 'been twice subjected to the mineral operations: in having 'been, first, consolidated and erected into the place of land, and, afterwards, sunk below the bottom of the sea, in order, a se'cond time, to undergo the process of subterraneous heat, and 'again to be elevated into the place where they are now found?'

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The evidence on this subject, Dr Hutton conceived, was to be looked for, as in the case of granite, at the junction of the newer and horizontal strata with the primary' schist; and he had long sought in vain for such a junction; when he unexpectedly discovered the vertical strata, in the bed of the river near the town of Jedburgh, above which are placed the horizontal beds which extend along the whole country.'

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'Here at least,' he remarks, is the most difficult to conceive, if we are to suppose that the upper strata had been deposited before those below them had been broken and erected,' (which was, nevertheless, the Neptunian view of the question). It is much more probable to suppose, that the sea had washed away part of the broken and distorted strata below, before the upper deposit had begun. If this shall be admitted, it will be fair to suppose, that the disordered strata had been raised more or less above the surface of the ocean; that by the effects of either rivers, winds, or tides, the surface of the vertical strata had been washed bare; and that this surface had been afterwards sunk below the influence of these destructive operations, and thus placed in a situation proper for the opposite effect the accumulation of matter prepared and put in motion by the destroying causes.'

This view was confirmed by his discovering an indurated conglomerate, a certain pudding-stone,' such as occurs in many other places in a similar situation, containing worn and rounded fragments of the schistus, interposed between the latter and the horizontal strata. The relative position of all these rocks is represented in a sketch by Dr Hutton's companion, Mr Clerk of Eldin; which we shall copy, both as an excellent illustration of the argument, and a specimen of good sound geological workmanship.

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b. b. Pudding-stone.

a. a. Horizontal strata of sandstone.
c. c. Vertical strata of schistus.

But, it may be asked, how the horizontal strata above, among which are many very strong beds, have been consolidated?—The answer to this question is plain :-Those strata have been indurated or consolidated, in no other manner than the general strata of the earth, these being actually the common strata of the globe; while the vertical or schistus strata are the ordinary strata still farther manufactured (if we may be allowed the expression), in the vicissitude of things, and by the mineral operations of the globe.'-P. 439.

And afterwards, having produced other cases of similar character in Scotland, the west of England, Germany, and Piedmont, Dr Hutton comes to this general conclusion

That in this example of horizontal and posterior strata placed upon the vertical schisti, we obtain a farther view into the natural history of this earth, more than what appears in the simple succession of one stratum above another. We know, in general, that all solid parts of this earth which come to our view, have either been formed originally by subsidence at the bottom of the sea, or been transfused in a melted state from the mineral regions among those solid bodies: but here we further learn, that the indurated and erected strata, after being broken and washed by the moving waters, had again been sunk below the sea, and had served as a bottom or basis on which to form a new structure of strata; and also, that these new or posterior strata had been indurated or cemented by the consolidating operations of the mineral region, and elevated from the bottom of the sea into the place of land, or considerably above the general surface of the waters.'-P. 449.

There would be no room here for our quotations, if we were to extract all that bears upon the identity of Hutton's doctrines

with those at present entertained. We must therefore content ourselves with referring our readers to the original work; which, if they can tolerate frequent repetitions, and occasional obscurity, of style, they will find, in substance, to repay the most attentive perusal.

III. But, whether true or erroneous, original or borrowed, the views proposed by Hutton failed to produce general conviction at the time; and 'several years elapsed before any one showed himself publicly concerned about them, either as an enemy or a friend.'

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Professor Playfair ascribes a part of this neglect to the fact, that the world was tired out by unsuccessful attempts to form geological theories, by men often ill-informed of the phenomena ' which they proposed to explain;' and to this he justly adds, "the brevity with which the system was first proposed, the embarrassment of the reasoning, and other defects which ran more or less through all Dr Hutton's writings, and produced a degree of obscurity astonishing to those who knew him, and who heard ' him every day converse with no less clearness and precision than animation and force."

But a still more important agent in the unfavourable reception of Hutton's book, was the supposition that his views led to religious infidelity. We have no desire to renew the discussion of any of those questions, on which Dr Hutton was so ably defended by Professor Playfair; and to which we adverted in our former article. But it may be observed that the part of Hutton's speculations thus objected to, though perfectly distinct from the physical enquiry, was dwelt upon as if it were the great object of his system; and that the hostility thus roused by an extrinsic and unsubstantial portion of his works, was visited upon the geological theory; while the very same objectors omitted to notice the numerous passages throughout his volumes impressing the benevolence and power evinced in the structure of the globe, some of which would do credit to the best of the Bridgewater Treatises. We have Professor Playfair's testimony, in addition to internal evidence, as to the great interest connected with these views by Dr Hutton himself.+

It is remarkable that, even at the present day, the supposed discordance or agreement of geological results with the small portion of the Mosaic history which relates to the Creation and the Deluge, is a frequent subject of public discussion, We hoped

*

Playfair's Works, IV. pp. 63, 64.

+Illustrations, SS 119, 126

that this question had been disposed of, by the common consent of all reasonable men, whether divines or natural philosophers; and that the whole tribe of authors- the Buggs, and the Nolans, and the Formans,' whom Professor Sedgwick* has consigned to notoriety, and who agree only in the most absolute ignorance of the department of natural philosophy which they pretend to discuss-had been utterly extinguished

The times have been

That, when the brains were out, the man would die,
And there an end: but now they come again,

With twenty mortal murders on their crowns,

And push us from our stools.'

It would be waste of time to continue a contest with writers whose object, in many cases, seems to be little more than notoriety, or the gratification of zeal so ill regulated as to deserve the name of fanaticism. The better course, we conceive, will be, to disregard them; with a conviction that in a very few years they will disappear, like the opponents of Copernicus and Newton, before the advance of truth.

To remove some of the impediments to the general reception of Hutton's doctrines, arising from the defects of his own publications, Professor Playfair produced in 1802 (five years after the death of the author), his well-known Illustrations of the Huttonian Theory;'-a book so justly admired, that we should have thought it secure of universal popularity, were there not proof that it is still but little known in France, and, as we believe, in Germany. But, although this work has unquestionably produced a strong and permanently useful effect on the character of geological speculation in England and Scotland, the knowledge of the structure of the globe was too limited and too rare, even in 1802, to admit of the rapid diffusion of any theory of the earth. It may be truly said that, on the death of Dr Hutton (in 1797), few, if any, geologists were left in Britain of acquirements at all comparable to his own.

One effect of the popularity of Playfair's 'Illustrations' has been an almost complete oblivion of the original work, which is now

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* The fearlessness and simplicity with which this able and excellent man has, on various occasions, expressed himself on the subject mentioned in the text, deserve the highest praise. See his Discourse on the Studies of the University of Cambridge,' p. 106; and Anniversary Address to the Geological Society,' 1831.-Proceedings, Vol. I. pp. 313-15.

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A French Translation of this work, and of Dr Murray's Comparative View of the Huttonian and Neptunian Systems,' was published at Paris, in 1815, by M. C. A. Basset.

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