were afterwards enveloped in the fubftances immediately fucceeding, which then continued to produce an homogeneous mass of ftrata, till some new revolution happened on the bottom of the fea; when the whole former mass of ftrata, including the brecciated, was again broken and difturbed, often with the finking of great parts of their mafs, which were then covered by new ftrata of other kinds, the first of which enveloped fragments of the whole former mafs fcattered over it.

Gravel, therefore, with which fome of our thores abound, is alfo found, even abundantly, in fome parts of the folid mafs of our continents; but does it follow that our strata are compofed of fuch materials as we find on our fores? Far from it; it follows, from the above and other phænomena, that the greatest part of the gravel obferved on our fhores, as well as over the whole furface of the continents; proceeds from the fame general caufe which, as here explained, has produced the brecciated ftrata; and if Dr. H. had attended to what is known of the circumstances of gravel, both in the internal mafs of our continents and on their furface, which manifeftly indicate revolutions after revolutions on the bed of the former fea they would have oppofed in his own mind, this first, and all the other propofitions of his theory; efpecially when he began to find, that the claffes of granite and of quartzy schisti, both by their fubftances and their actual fituation, could not agree with the firft expofition of his fyftem.

But let us now grant him his exclufion of these two claffes of ftrata, not from any appearance of reafon, but to fhow how far he was mistaken on the whole. What part of the folid mass of our continents fhall we then confider as having been immediately compofed," either from the relics of fea animals, or from fuch materials as we find on our shores ?" It must be the whole of the ftrata formed on the fchifti; and, in order to know their first fucceffion, we must return to the great chains of mountains, to these vast fractures and diflocations of the mafs, which form their vallies; fuch, for inftance, as the valley of the Rhone within the Alps, quoted by Dr. H. himself from M. de Sauffure's defcription. By thefe leading features of our continents we learn, that, on the fchifti, was immediately laid an immenfe mass of lime-ftone ftrata, fucceffively of various fpecies, which, in their prefent ftate of fubverfion, not only compofe the outfide ridges of thefe chains, but many other more distant ridges, such as thofe of Saleve and Jura with respect to the Alps; that, to the lime-ftone, fucceeded im mediately, in moft parts of the ocean, a great mafs of fandkone strata; after which, and many revolutions, various forts

of

of ftrata, homogeneous in their kinds, including the coals and their concomitant ftrata, were produced over the ruins of the antecedent ftrata. Now, in what part of the fea or land were fand, gravel, and argillaceous fubftances detained, while the fuppofed relics of fea animals formed, immediately on the fchifti, that immenfe mafs of lime-stone, ftrata?-Where remained afterwards thofe relics of fea animals, and the gravel, while the fand-ftone ftrata were formed immediately on the lime-ftone? Why was the formation of lime-stone, fuppofed to proceed from fea animals, never repeated after the production of the great mafs of fand-ftone, or, in other parts of the fea, after that of the coals and their concomitant ftrata?

Thefe are indifpenfable queftions, on which not a word is found in the whole work before us. But, while we see the author reproaching Mr. Kirwan, for having only confulted the objects feen in cabinets, in judging of our ftrata, and only his own chemical operations, in confidering those of nature, he has much more confined the field of his refearches, at the fame time that he aimed at the vast object of a theory of the earth. We shall give another inftance of the fhortness of his fight, by examining the following propofition; and, as we have now proved, that it is impoffible to account for the formation of our ftrata, by fuch materials as are found on our shores, it will not be furprising to find alfo, that none of these materials are, or can be, tranfported over the bed of the ocean.

PROP. III. The materials of decaying continents being Jucceffively, by the action of rain-water, delivered on their Shores, are there taken by waves, tides, and currents, and Spread over the whole bed of the fea.

After the first publication of Dr.H.'s theory, this propofition, which is contrary to the received opinion, and was laid down by him without a proof, was ftrongly oppofed; this he paffes unnoticed, and only repeats his affertions, which are as follow.

(Vol. I. p. 13.) "In no fubject, perhaps, is there lefs defect of evidence, although philofophers, led by prejudice, or mifguided by falfe theory, may have neglected to employ that light by which they fhould have feen the fyftem of this world... (p. 14.) The moveable materials delivered into the fea, cannot, for a long time, reft upon the fhores; for, by the agitation of the winds, the tides, and the currents, every moveable thing is carried farther and farther along the fhelving bottom of the fea, towards the unfathomable regions of the

●cean.

That

That every moveable thing that lies, not only on the fhores, but on the bed of the fea, at a certain diftance from the coafts, is moved by the agitation of water, is certain: but in that motion, which is the direction that prevails on the whole?This question has long been decided among obfervers; there is no doubt that the most common direction is towards the fhore, and this acknowledged fact has even ferved as a foundation for feveral fyftems contrary to that of our author. M. Le Cat, for inftance, publifhed, about fifty years ago, a theory of the earth, in which, confidering the fea as conftantly tending to hollow its bed, by throwing new materials on the fhores, he attributed to this caufe only, the production of our continents. It was, no doubt, a very infufficient caufe; for, though the fea be constantly tending to throw materials out of its bed, the effect is only produced while the afcent towards the shore is not too rapid; and it is ftopped when, by the materials already come out, the neighbouring parts of the fea are hollowed beyond a certain degree: befides, that operation cannot fenfibly affect the refpective levels of fea and land; fince, in proportion as the fea becomes deeper, it is more contracted by the increasing land. The operation, however, is real, and conciliated fome attention to the theory: but, not to oppofe only opinion to opinion, let us examine the nature of the acting caufes, and the effects which they muft produce.

While that shelving plane, extending from the fhore under the fea, on which the author depends in his whole fyftem, has but a small declivity, it has very little influence on the motions of the loose materials lying upon it; the caufes of their actual motions are the waves, the tides, and the currents. The two first are most active on our fhores, and they have this in common, that, when their motion is directed towards the fhore, they are preffed forward by the mafs of water which follows them in the rear, and have thus a great power to propel before them the loose bodies which they meet in their way; whereas, in their retreat, they act only by their own preffure, that of a decreafing fheet of water. This is a clear cause of the general facts obferved on the coafts; that, in every part where the fea is ftill fhallow, the fhore, or ftrand, gradually extends forwards; and that when, by that operation, the declivity of the fhore has increafed to a certain degree, the loofe materials are only moved backwards and forwards on the flope. If, on the contrary, the fea has originally been deep near the coaft, and the land fteep towards it, the waves and the tides have had the power to bring down the loofe materials, on acsount of the great declivity; but this is gradually leffened, by

the

the materials extending forwards, till at last the flope has arrived at that degree of declivity, where no more effect is produced. In both cafes, the tendency of the waves and the tides to throw materials out of the fea, ftill remains, but the degree of afcent opposes their effect, and no further change is produced.

As for the currents, it is known alfo that they do not affect the bottom of the fea at any great depth: the upper parts of the water yield first to the caufes of motion, and the equilibrium is produced before the motion has been communicated to the deep mass, so as to have any effect on the materials lying at the bottom. The only action, therefore, of currents on loofe materials, is along the coafts, where their effects are also well known: they attack the projecting lands which oppose their courfe, and, if thefe lands are compofed of loofe materials, they are gradually wafted; but, when the moving water, having doubled thefe capes, is arrived into fome recefs of the land, lofing there its rapidity, it foon abandons the fand and mud, which it carried away from the projecting lands. Thus bays, creeks, and harbours, along the coafts, are gradually filled, where fome projecting land is effectually attacked by the fea, till an eafy turning is produced by the currents themfelves; and then their effect, which tends only to smooth the original indentations of the coafts, is alfo at an end.

Thus is contradicted, in every refpect, by facts and mechanical principles, that theory of lands wafting in order to produce new lands, which appears fo clear and fo wife to this author : the pretended demolition of continents, fuppofed by him, as will be feen, the greatest good for living beings, would only increase the extent of thofe which exift, by lowering them, without affording any materials for the production of new continents in the unfathomable regions of the ocean; for, every motion of its water, would prevent the loose materials from abandoning the mother land. The remaining propofitions of Dr. H. we must referve to another opportunity: nor shall we fpare our pains in giving them their due examination. Vifionary theories of the earth are never without their reference to matters of a higher import and our readers will, we doubt not, think that attention well beltowed, which terminates in proving that the doctrines delivered, on the higheft authority, are alfo thofe which beft, correfpond with facts and obfervations.

(To be continued.)

ART.

ART. II. Purfuits of Literature; or, What you will. will. A fatirical Poem, in Dialogue. With Notes. Part the Second and Third. 8vo. 15. 6d. each. Owen. 1796.

WHOEVER diftributes cenfure and praife, with a bold hand, and a certain fhare of ability, to many public characters, will, if he remains concealed, excite no fmall curiofity refpecting himfulf. This has been completely done by the writer now before us. Many are the conjectures we have heard, but none to which we can give aflent. Our own mode of gueffing is altogether of a literary kind; we pretend not to fay who he is, but what he has done. We have, no doubt, (as we have before said) that the writer is the fame to whom we owe the Epiftle from Kien Long," noticed in our fixth volume, p. 230, and the "Political Dramatift," noticed in vol. vii. p. 427: The latter indeed he now almost avows, by his mode of recommending it, in a note, part ii. p. 33. The author, like Junius, protefts that his fecret will remain unbroken. ་་ That it will attract fome attention in me places, I am confident; but it will be idle to make any conjecture as to the author. He is, and will be, concealed, upon motives very different from the apprehenfion of any private refentment." To this declaration he fubjoins a kind of threat, which, however, will not reprefs the activity of curiofity, nor the prefumption of thofe who will pretend to know whatever is a fecret. One negative piece of knowledge feems obvious enough, that he is not an Etonian, for which he holds himfelf out. The true Etonians declare this, from a few internal marks; and others can easily suppose that an author, wishing to be unknown, would not thus limit and define the region of enquiry.

The fift part of this fatire appeared in 1794, and was reviewed in the fourth volume of the British Critic, p. 301. What we then thought of the powers of the writer, is ftill our 'opinion, with fuch difference as may naturally arife from having feen much more of his exertions. We rank him not with the higheft, though far above the generality of writers. in his clafs. His tafte and knowledge are claffical; and he applies, with fpirit and effect, remarkable paffages from the beft writers, ancient and modern. His lines are frequently well-pointed and vigorous, but not always carefully polished. His tranfitions are abrupt and careless, which throws a confiderable degree of obfcurity over the whole. He repeatedly warns C c

BRIT. CRIT. VOL. VIII. OCT. 17965.

his

1