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producing earthquakes exerts its influence at vast distances, and therefore must be situated at a great depth below the surface.

“ In the year 1755, when the great earthquake happened, by which every part of Europe and all the north of Africa were shaken, and Lisbon was destroyed, Loch Lomond in Scotland was observed to be in a state of uncommon agitation, without any apparent cause. In Loch Tay such a phenomenon is not unusual when every thing around is calm. The same frequently occurs in the Lake of Geneva, which suddenly ebbs and flows, when there is not a breath of air to agitate its surface. The cause, therefore, must be internal, and may be sought for in the agency of subterranean fire.” (P. 360, 361.)

On the whole, we believe the volcanian hypothesis will gain much by the collection of facts and the judicious reasoning furnished in its support by Mr. Townsend; and we are inclined to consider it as the most probable of the geological speculations which have been maintained. But though we think our author has chosen his ground with discernment on the great scale, we can by no means assent to the manner in which he fills up particular positions. We cannot, for example, conceive how the other primitive rocks can be considered as the offspring of gra. nite. Granite is stratified, and it is crystallized; therefore it was deposited from a chemical solution ; and if the waters of the ocean held the materials of granite in solution, why may they not be supposed to have precipitated the other formations successively, as gneiss, mica-slate, &c. which recede gradually in their composition from the nature of granite. An inspection of the texture of these rocks, and the crystalline minerals which constantly accompany them, is sufficient to prove the fact.

We are not more disposed to agree with our author in his opinion of the origin of granular marble. He supposes it to have undergone igneous fusion, and to have lost the vestiges of organic bodies in consequence, and affirms it to be connected with volcanoes. But granular marble is a primitive rock, the beds of which are generally found subordinate to the mica-slate formation. Von Buch traced it in this formation through a great part of Norway: it is impossible to refer its origin to fusion, without involving the primitive formations which contain it, in the like predicament. Its situation, moreover, is such as to preclude the idea of its ever having contained organic bodies, or having been in any manner the product of volcanic operations.

But it is now time to add a few remarks on the proofs of the universal deluge. The foregoing view of the convulsions to which our globe has been subjected prepares us for the admission of this wonderful catastrophe. The geological theory adopted by Mr. Townsend is highly favourable to this part of the Scriptural history. If we can trace the actual operation of agents sufficiently

powerful to elevate the continent of South America, and other extensive regions from the depths of the ocean, it is no longer difficult to conceive that the waters may have covered the highest mountains, and that great tracts of habitable land may have been submerged. But absolute and distinct proofs of this event are to be found in the dislocations of strata, and in the phenomena connected with alluvial depositions.

There is no part of the earth in which the violent dislocations of the regular strata are not to be found, and they are chiefly abundant in mountainous tracts, of which no other proof need be cited than the vertical position which the strata forming high mountains now hold, while we are assured that these very strata were originally horizontal. But even in the most level countries we need not go far for evidences of these convulsions. Every river, every brook which breaks out under our feet, and every valley which diversifies the surface, owes its existence to the disruption of strata. All the rock formations were at first unbroken and continuous ; wherever a valley occurs there is now an interruption of this continuity. That these hollows were not the mere effect of rivers which have worn out courses for their waters may be proved by a variety of geological facts which we have not room to introduce here; but it is put in a sufficiently strong light by Mr. Townsend's observations on springs, which are in a great measure new, and of very general interest. Every stratum of rock, before it becomes broken up, carries with it in its course under the surface a stratum of water, which percolates its stony beds, and is confined between impervious layers of clay. It is only where these subterranean courses are disturbed, and the strata are torn asunder by some extraneous force, that fountains and rivers burst forth. These dislocations and disturbances of strata can only be attributed to the agency of vast torrents every where flowing over and disorganizing the surface of the earth, and such torrents can only be furnished by the incursions of the ocean. Land floods and rivers are the effects of the previous disruption of the strata, and therefore cannot be considered the efficient causes.

That these phenomena were produced by the waters of the ocean is further proved by alluvial deposit.' The vast extent of alluvions, independent of all other proof, declares that the ocean gave them birth. One great accumulation of debris fills nearly the whole of Flanders and Holland; it reaches across the Channel, and covers the southern and eastern counties of England, concealing under it, at a great depth, the regular strata of these districts. Another alluvion forms Lower Saxony and Holstein. Similar appearances occur in all level countries, and valleys are generally filled with these accumulations, through the midst of which the feeble streams of the present rivers have opened for themselves diminutive channels. That these accumulations were effected at once by vast oceanic torrents, and not by the gradual influence of rain and land floods, appears, Mr. P observes, from the alluvial strata not being mixed or blended together, but frequently disposed according to their specific gravity. The vast fragments of rock which are found scattered over plains and mountains, in so '

many parts of the earth at great distances from their native mountains, lead as forcibly to the same inference.

“Such are the enormous rocks which formerly constituted the pride of Abury, and are still admired at Stonehenge. Similar bowlder stones, in point of size and bluntness of their edges, I remarked in Spain, on the summits of the highest hills near Cordova, some of mountain limestone, some of silicious grit, and some of granite, all promiscuously scattered on the same plot of ground. This could not have been effected either by land floods or by the detritus of incessant rain, through endless generations. The same may be said of the alluvial strata, mentioned in my Spanish Travels, as being deposited on the high mountains near Guadix, between Granada and Carthagena, in which appear promiscuously, gravel and quartz schist, lime-stone, and Aint, all rounded at the edges." (P. 237.)

The prodigious masses which lie on Mount Jura, and certainly descended from the Alps, though the Lake of Geneva lies in the way to intercept their course, and which so much interested Saussure and Deluc, is the most surprising phenomenon of this kind.

One of the most important observations which relates to these deposits is the following:

“ In all the alluvial districts here particularly noticed, it appears, that only one bed of vegetable earth is to be seen. Consequently these strata have not been produced by land floods, at different and at distant periods. They direct our attention to one epoch, and most distinctly give us a measure, by which to estimate the time which has elapsed since either the elevation of our present continents, or the depression of the surrounding seas." (P. 236.)

We are assured, that the incursion of the ocean over the habitable surface of the earth took place at a time since it was actually inhabited by land animals, by the organic remains which the alluvions contain; and this remark leads us to our author's disquisition on the interesting subject of extraneous fossils, with which we shall close our observations on his work.

Mr. Townsend is the first who has given as any extensive account of the organic remains, in connexion with the strata to which they belong; and in this respect he has rendered so acceptable a service to the public, that his work would claim a degree of consideration on this merit alone. This connexion

constitutes the chief interest of the study of these remains; and it should be the object of all those who follow this pursuit, to illustrate it by every fact of which they become possessed. We have no room here to analyse our author's observations on this subject, and can only notice, in general, that they coincide with the sagacious remark of the Professor of Freyberg, who first traced a progressive series in the animal creation. The oldest class of rocks contains no vestiges of organized beings, and this fact is sufficient to silence the assertion of Hutton, that the world exhibits no traces of a beginning. Lithophytes and shells occur in the oldest secondary rocks, and more complicated beings gradually make their appearance. All these, however, and indeed all the organic remains occurring in strata which have never been disturbed and disintegrated, may be termed indigenous. It is plain, that the creatures of which they are the spoils lived and died on the places where they are here traced. The shells are found deposited according to families, and confined in a great measure each to its own stratum; and a similar remark applies to other animal remains of this department. It is not so with those of alluvial ground. These are assembled from all parts of the earth, and are thrown together in promiscuous heaps. In the same beds are found shells and corals oniy known in the Pacific Ocean, and the bones of elephants and rhinoceroses.

“ They seem (says Mr. Townsend) to have been transported from distant climates, and to have been deposited in a tumultuous manner by some grand convulsion, which blended and buried terrene and submarine productions ancient and recent, in one common grave.”

“ The direction in which they have been conveyed, appears to have been from S. E. to N. W. Hence, where we have an opportunity of making distinctions respecting their natural habitations, as in the Asiatic and African elephants, it is remarkable that the former, and not the latter, are to be found fossil in the North of Europe.”

“ Should the latter have been transported from their native seats by the same convulsion, it is probable that their reliques lave been deposited in the Atlantic Ocean." (P. 255.)

We regret that our limits will not allow of our extracting more from this essay on organic remains, which is highly interesting. The productions of M. Cuvier, who was assisted by all the facilities which the despotic power of France insured for her scientific men, contain more information concerning the relics of the more perfect orders of animals; but, with respect to that admirable series which belongs to the rock formations, properly so called, and by which the creation is to be traced, as it were, from its beginning, we must refer exclusively to the work of Mr. Townsend.

In perusing this work, we have frequently found reason to re

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gret, that the author has not adopted, in his geological descrip tions, the more precise nomenclature of the Wernerian School; which, in spite of all the clamour raised against its dissonance by a set of dilettanti, has gradually made its way into general use, and is not likely to lose the prevalence obtained by its now undisputed merits. Our author's geological descriptions are so well drawn, that they are intelligible, though expressed with the more vague terminology of the older naturalists; but we could point out passages, which would be much more perspicuous if he had adopted one more accurate.

It is no disparagement to so extensive a work to say, that it contains errors. We must confess, however, that a remark made by Mr. Townsend on the celebrated tradition of the Terra Atlantidis has surprised us. He is inclined to believe that such a country formerly existed, because the supposition explains the existence of monkeys, crocodiles, and other animals of warm climates in the new world, which may have passed across it from Africa. This certainly is more probable than Pennant's conjecture, that all the animals in question passed the frozen north, and have since undergone a change of constitution; but both these conjectures are confuted by the stubborn fact, that none of the American animals of warm climates are found in Africa or Asia; and it appears certain that the new world had its appropriate creation.

On the whole, we have no hesitation in saying, that we consider this volume as a valuable acquisition to the public, both as a work of natural history, and as supporting the authority of the Mosaic records ; though perhaps it might have been more generally useful in both points of view, if its arrangement had been more logical and systematic.

Art. III. The Excursion, being a Portion of the Recluse : a

Poem. By William Wordsworth. 4to. pp. 423. Longman. It must be avowed, that this poem is as a " sealed book” to no inconsiderable number of readers. To those whose imaginations have been kept continually on the stretch, and whose curiosity has been perpetually stimulated, by wonders of romance; by tales of Gothic chivalry; by donjon, and keep, and battlement, and banner; or by wild mythologies and exotic manners, American, or Indian, or Turkish ; the quiet simplicity, the mere mental elevation of the Recluse," offer little attraction: to those, also, who have habituated themselves to consider an uni

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