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affect the tropical latitudes, being found in the lime-stone of northern Europe, is no unequivocal proof of extensive and stupendous catastrophes; since the phænomena in question may, with at least equal plausibility, be ascribed to changes in the constitutional temperature of our planet.

That portion of the work, which describes the extraneous fossils of our own and other countries, will be found highly deserving of perusal; especially by those who are strangers to the writings of De Luc, Pallas, Saussure, Parkinson, &c. Among the relics belonging to the inferior oolite, the Madrapora cinerascens is thus specified :

• The coral bed contains the Madrepora cinerascens, which is found recent in the Indian seas. One of these curious petrifactions was standing upright more than five feet high, and expanding nearly six feet, with a double cup, much fractured, but no fragment is scattered to a distance. It was, A. D. 1802, examined by several gentlemen. The remains are to be seen near Midford, in the lane leading from thence to South Stoke. .In its cavities it contains numerous coated mytili, with their cables covered by a crust, on some of which corals have begun to build.'

Mr. Townsend's descriptive catalogue of animal and vegeta able remains is, however, far more extensive and minute than the purpose of his argument required. His suggestions concerning lime stone, that is generally reputed primitive, are not unworthy of consideration :

In no part of Great Britain have I seen a primitive limestone, that is, such a lime-stone as in none of its beds contains extraneous fossils. I have indeed seen many rocks which do not readily exhibit the fossils (which) they contain, unless these have been brought to light by polishing. Alternating with such beds, we find others, in which shells and corals are extremely rare, or which seem to be composed entirely of calcareous paste, as in our lyas, whose fossils are confined principally to its intermediate beds of clay.

In the most perfect of Italian marbles, we have indeed no extraneous fossils, but it does not therefore follow that such rocks are primitive. They are in the vicinity of granite. They border on basalt, and other volcanic productions. They have not the least resemblance to our imountain lime-stone, or other calcareous rocks, formed evidently by subsidence in water. They are semi-pellucid, and in their fracture have a crystalline appearance,

«These circumstances have long since made me suspect the agency of fire, and now the experiments of Sir James Hall confirm my suspi. cions. He has had the goodness to shew me some of his marble, produced by fusion under pressure, equal in its appearance to the Italian. The term primitive lime-stone seems therefore to be improper, and the reason why no extraneous fossils are to be found in the Carrara marble may be, that the whole mass of this carbonate has been in fusion.'

Q.4

Mr. T.'s! Mr. T.'s main object, in exhibiting a copious enumeration of organized remains in a petrified state, is to prove that our present continents were, for ages, covered by the waters of the ocean ; a position which few intelligent naturalists will be disa posed to controvert : but that the shifting of the channel of the sea, and its diffusion over its present beds, constituted the phænomenon of the deluge recorded by Moses, may not be so readily conceded either by the geologist or the divine. It is true, indeed, that the term days has been construed into periods of indefinite duration, so as to allow ample time for the consolidation of the strata : but, if we make thus free with the pointed and precise language of Scripture, where are we to stop, or how shall we draw the line between literal and figura tive interpretation ? Again, the ark seems to have quietly reposed on known ground; while the olive-leaf, plucked by the dove, and the vineyard planted by Noah, would indicate a return to the former physical condition of things. In short, if the flood universally prevailed over our planet, and to the height of fifteen cubits above the highest mountain, we must believe it as a miracle, and not vainly attempt to explain it by any reference to the known and established laws of nature.

From the section on Springs, we learn that they follow the courses of their containing strata ; a doctrine of much practical import to landholders and engineers, but which seems to have no immediate connection with the Mosaic account of the Deluge. — Vallies are represented as the effect of subsidence, and not erosion; consequently, as originating in the debacle of the Deluge, and not in the slow but incessant waste produced by the attrition of rivers. Yet the converse of the proposition is, perhaps, equally tenable.

Under the article Consolidation of Strata, the attention is principally directed to the process of petrifaction, which Mr. Townsend is particularly sollicitous to ascribe to aqueous deposition, and not to igneous fusion. Now, we are not certain that either hypothesis will satisfactorily explain all the phænomena ; and, perhaps, the idea of chemical conversion, sug, gested by Patrin, is less chimerical than we might, at first sight, suppose. At any rate, we must believe that, in many instances, the process of silification, whatever it may be, takes place with great rapidity. Some specimens of wood-stone, for example, exhibit not only the most entire organization, with the shades of each fibre, but worms, which are themselves converted into agate, with their external surface whitish and opaque, and their interior characterized by waving zones, of different tints, pourtraying the intestines. The annual circles of the wood, and the medullary prolongations from the centre to

the

of Lons-le-Saubrine pit. The she was converted inton

the circumference, are distinctly traceable; and it is particularly worthy of remark that the only unsilicified parts are precisely those which had suffered decomposition. At Naufle, near Grignon, have been found morsels of agatized wood, which contain a multitude of the larvæ of insects, retaining their natural form. In others, the caterpillars are observed to be moveable in their cavities; a circumstance which is not easily reconcileable to the infiltration of aquatose fluid that would have consolidated the mass. Saussure informs us that the cabinet of M. Annone, at Basil, includes a fossil crab, of which even the ova, under the tail, are petrified. Some petrified fruits might likewise be quoted, on the present occasion; particularly the fossil walnuts of Lons-le-Saunier, which were found at the depth of 180 feet, in an old salt-brine pit. The shell and rhind retained the ligneous texture, while the kernel was converted into silex. In Davila's catalogue, mention is made of similar specimens, found in Piedmont: of which the colour and appearance are so little changed, that a person would be tempted to eat them, though the inner part of the shell presents not the smallest vestige of infiltration. The case of Trajan's bridge over the Danube, which Mr. Townsend cites with perfect complacency, needs not to be regarded as an exception to this view of the subject; for we can easily conceive siliceous incrustation or deposition taking place very slowly, and being, in fact, a very different process from the transmutation of large trunks of trees into stony matter, by the union of aëriform fluid with the elements of an organized body. Or, if the petrifying progress must be measured by that of the incrustation just mentioned, its extreme tardiness would denote a higher degree of antiquity than the author had probably contemplated, or than would suit the exigencies of his theory.

The operating causes of the dislocation of strata are here attributed to the joint agency of fire and subterranean currents of water. That the first of these has exerted more powerful and extensive influence than many have imagined will be readily admitted : but every candid inquirer will be disposed to have recourse to some cause of more uniform and simultaneous operation, in order to account for the inclination of strata which pervade whole countries. The effects produced by subterraneous currents of water are thus explained :

• A different species of dislocation, wholly unconnected with the preceding, has been noticed on the northern extremity of Lansdown and at Derry Hill. Such dislocations are extremely common. To understand their nature, we must call to mind, what has been said of strata, and of springs, and must consider, what is passing at the present moment in the bosom of the ocean.

. We

< We have seen, that the copiousness of springs depends on the extent and thickness of the filtrating strata, and that these strata are inclined to the horizon. We have likewise seen, that in cases of rupture and dislocation in the strata, springs may break out either laterally, as at Calstone and Pottern, or perpendicularly upwards, as in every country in which quicksands appear. But should the stratum of water, produced by rains and dew on a considerable expanse of country, and filtrating through its proper bed, as, for in. stance, through the sand immediately under chalk, or through the great free-stone rock between Bath and Bradford, find either no vent, or one not sufficient to exhaust its contents in the formation of springs and rivers ; it must continue to descend over its inclined plain of clay, in its progress towards the centre of the earth, till the top covering, unable to support its pressure, shall give way, and a disruption shall take place. This must naturally happen where, in the bed of the ocean, the incumbent mass of rock is least considerable.

• The consequence of this disruption and discharge of water, will be a current in the direction of the filtrating stratum, dependent on the quantity of rain and subject to alternations whenever the supply proceeds from a country, which has its seasons of drought and rain. As the direction of the dip varies in different parts of the globe, so must the direction of the currents, meaning always, not the superfi. cial, affecting navigation, but the ground currents perceptible only by the plumb line.

• Now, although we cannot look into the deep, we may be certain, what must be the effects produced by submarine torrents rushing from their beds and pouring forth their copious streams into the ocean. They are two-fold, for first the momentum acquired in a long and rapid descent is not readily destroyed. This we observe in the waters of the Rhone, which for many leagues pursue their course in the Mediterranean Sea, perfectly fresh, without the most minute admixture of salt water. But if such be the momentum in the waters of the Rhone, how much greater must be that of torrents rolling down much steeper descents; and what a battering ram must they present to opposing strata of argil, sand, or other soft materials. Such materials must be washed away, and consequently the superincumbent strata, even of the hardest rocks, must

fall.

• But in the second place, such a plentiful supply of water, once in motion, must inevitably dislocate much of the filtrating stratum, in which it was collected, with the clay on which it glides, and thereby let down the superincumbent strata.

• This process is taking place in the present ocean, and may have existed in the former. But, however the effect in question may have been produced, certain it is, that superior strata were undermined, and that considerable incroachments were made on the inferior strata by which numerous superincumbent beds sunk down. Such incroachments cannot have been produced by the common agents of destruction, rain, dews, frost, and wind. They must, therefore, have originated in the attrition of inferior currents, however caused,

whilst these strata and the now habitable parts of the globe were covered by the sea.

• The scattered fragments of the dislocated strata being perpetually in motion, and agitated by contending currents, may have formed shingle, precisely like the alternations of the tides, on our sea shores, and the same operation may have produced bowlder-stones, which cannot have been formed by land floods and torrents.

. On these scattered fragments, some angular, others, by agitation and attrition, rounded, various substances, such as clay, sand, broken shells, or the paste of these, having been deposited, may have given birth to breccia and pudding-stone.'

The observations on Dr. Hutton's Theory of the Earth, which follow next in course, are prefaced by the ascription of motives to the author of that theory, who can no longer answer for himself. Mr.T. says, "He was not an Atheist; but, as far as we can judge by his writings, a firm believer in the wisdom and power of the Creator. His object, therefore, in this work, was not to establish atheism, but to justify his unbelief in Revelation, and to make converts to his infidel opinions. If sincere and enlightened divines have openly maintained that the Bible was not destined to instruct us in the principles of physical science, and that the interests of Revelation cannot be affected by the highest antiquity which can be assigned to the existence of the globe, we may charitably presume that Dr. Hutton's investigations were prompted by the purest zeal for truth, and that the idea of disturbing the faith of the narrow-minded interpreters of Scripture was beneath his notice.- In Mr.Townsend's review of this celebrated theory, several forcible objections to some of its leading principles are stated ; and we much mistake if difficulties of equivalent weight will not be found to press on every theory of the earth that has been hitherto proposed. At all events, the discussion of the two rival systems of fire and water has been too frequently agitated, to afford either instruction or amusement to our philosophical readers.

In the section on Chronometers, the existence of Delta soils at the mouths of rivers, -- accretions at the entrance of rivers into great lakes, – the gradual conversion of lesser lakes into marshes, and then into meadows, — the recent formations of peat-earth,- the choaking of bays, creeks, and æstuaries, the retrocession of the Baltic, &c., are adduced as so many physical proofs that the origin of our continents is not more antient than the period of the Deluge: but the advocates for the indefinite antiquity of the world may allege that these measurable diminutions of the quantity of fluid are, comparatively, of yesterday, and that former waters may have repeatedly accumulated and receded in the lapse of ages.

Under

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