altogether from its bosom ?The attractive force that made the solution should have maintained it. To imagine an effect to come to pass without a cause, is sufficiently ridiculous, though not without a parallel in modern philosophy; but to expect a solidifying action, a stony deposit, from a liquefying agent, unabated in force and magnitude, is truly absurd. The other assumption of the clear and tranquil solution becoming spontaneously muddy and disturbed, as it parted with its solid contents, is repugnant no less to common sense, than to chemical experience. A still liquid containing soluble and insoluble matter usually deposits the insoluble, which is mechanically diffused, before the crystals appear, provided the latter be regularly aggregated, as occurs in granite. We shall not waste more words on this analysis; but conclude with expressing our astonishment that the theoretic dreams of Werner. should ever have been regarded as realities, in the present age." kome out a

The body of Dr. Ure's work is distributed into three books; each containing several chapters. The first book comprehends what may be called, on Dr. Ure's principles, primordial creation, including primitive rocks. Chapters I. II. III. treat respectively of heat, light, and the atmosphere. In Chapter IV., entitled" Primeval Land and Ocean," some of our author's new thoughts on the structure and revolutions of the earth begin to appear.,t

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Circumstances, which will transpire in the progress of our researches, cause me to assign a different proportion between the dry and humid surface in the primeval globe, from that which now prevails. I am led to conclude, that the area of the land bore, to that of the water, probably the ratio of equality, instead of nearly 100 to 365, as at present. One obvious consequence of this condition was, that the depth of the primeval ocean was greater, as its superficial expanse was less. By this means, the water came into far deeper and more extensive contact with those ignited, combustible, and explosive materials, which the phenomena of mines and volcanoes demonstrate to exist within the crust of the globe.".

> Multiplied observations have shown, that the crust of the earth is composed superficially, or to a moderate depth, of certain stratiform or schistose rocks, which, being devoid of organic remains, are termed primitive...We shall at present confine our attention to two of them, called gneiss and mica-slate. These are arranged in planes usually parallel to each other, the mica-slate being, for the most part, uppermostat: We have

reason to believe, that hardly any district of the terrestrial surface is destitute of these great slaty rocks, though in many places they may be deeply covered over with secondary formations, and therefore inaccessible. Gneiss constitutes the body of the Himmalaya mountains, and abounds among the Andes, Alps, Urals, Pyrenees. It forms also Ross island, the most northern known land of the globe. Mica-slate is nearly coextensive. But their wide-stretched foliated planes are seldom or never horizontal, or concentrate with the curvature of the earth. They usually lie at highly inclined angles, like tables resting on their edges, in a nearly vertical position. In very many localities, vast irregular masses of granite are seen rising up through the schistose fields, as if these had been upheaved and dislocated by its protrusion, and were thrown-like mantles round its shoulders and base.

We therefore conclude, that the primordial earth, as it lay beneath the circumfused abyss, was at first endowed with concentric coats of gneiss, mica-slate, and the other primitive schists; that at the recorded command of the Almighty, a general eruption and protrusion of the granitic, syenitic, porphyritic, and other unstratified rocks, took place, which broke up and elevated the schists into nearly vertical planes, similar to what now exist, leaving commensurate excavations for the basin of the sea.

"In meditating on this mighty operation, though we may shrink from the overwhelming scene, and feel our faculties abased, nay annihilated as it were, in the presence of that Power, who hath measured the waters in the hollow of his hand, weighed the mountains in scales, and the hills in a balance; who sitteth upon the circle of the earth, and stretcheth -out the heavens as a curtain,' yet the magnitude of these terrestrial disruptions will create no difficulty in the mind of the astronomer, familiar with acts of Omnipotence incomparably more stupendous. Even the geographer would smile at the geologist, who should ask for Deity a countless lapse of ages to build upon the earth its superficial scaffolding, whose size is to its total bulk, as the roughness of the rind to the ball of the orange."

The constitution of water, as described in this chapter, shows what interest a philosophical spirit may infuse into the tritest subjects. borah s Seje 10% 13 mmoluste mist

This water, by its mysterious tenuity, loosens the indurated soil, enters the invisible pores of plants, passes freely through all their vessels, expands in the filmy blossom, and is an element of the fleeting aroma, But these fluid particles can be

chained together in the firmest cohesion: in which state it may exhibit either the hardness of rock, or the softness of eider-down. Enormous blocks of water thus stand in immovable columns, surmounting the loftiest pinnacles of our globe. How different are these from the soft insinuating liquid, which is the circulating medium of all organic life!

Every common water in its natural state, whether salt or fresh, contains about a fortieth of its bulk of air, which it readily evolves either by the heat of ebullition, or when placed in vacuo. In these circumstances, we perceive minute globules oozing out from every point of the liquid, which when liberated, rise by their innate lightness and elasticity, in a pearly-looking stream to the surface. Now this liquified air is the element of respiration, the pabulum vitæ, to all bronchial animals. The gills of fish elaborate that liquid air, as the lungs of land animals do its elastic form. Both organs convert its oxygenous part into carbonic acid, for the sustenance of vegetation, terrestrial or submarine.

"Enough has now been stated to evince, that water in its liquid state is not the uninteresting, inert element which the multitude suppose it to be, but that its constitution is most refined and intentional, adapted to the manifold functions which it must discharge towards countless orders of organic and inorganic being. Its habitudes with heat are peculiarly beautiful. A certain energy of this power gives to water its liquid condition, in which, as already mentioned, the molecular attraction is very nearly neutralised by the repulsive force. Had the cohesion of its parts been less, it could not have afforded the reaction requisite for the movements of fishes and ships; nor could man have availed himself of its impulsion to aid his feeble arm in preparing his food, clothing, and domestic ac. commodation. The same calorific agency wafts the ponderous liquid on the wings of the wind, to supply the organic inhabitants of mountains and plains with vivifying moisture; or under the guidance of mechanic genius, it animates the steamengine, the noblest offspring of science and art, the unwearied and docile servant of man.

"The equilibrium of its mobility lies within narrow bounds. A very moderate reduction of temperature restores the cohesive power to uncontrolled dominion, under which the form of water ceases to exist, and might thus continue unknown. Again, had the particles of water been mutually elastic, though but in an inconsiderable degree, the least disturbance by winds or tides must have produced tremendous commotions in its mass; and a floating body would have been alternately tossed

into the air, and plunged into the depths, with destructive violence. Under such circumstances, the sea would have been an impassable gulf, between closely adjoining kingdoms, instead of being, as now, a thoroughfare between the most distant lands, the element of the noble art of navigation. By its almost inelastic and incompressible crasis, the body of the ocean cannot resile, nor suffer agitation beyond a few fathoms from its surface, even from the force of the hurricane. In fine, the absolute passiveness of water, and independent gravitation of its parts, form its most valuable qualities."

Chapter V. is occupied with primitive rock formations. Our author has here very properly availed himself of Dr. Maculloch's excellent papers on granite, published in our old series of the Quarterly Journal of Science-referring on this, as he does on all similar occasions, to his authorities. He has also turned to good account Von Buch's late observations on erup tive rock phenomena in the Tyrolese Alps.

We shall quote a paragraph from this chapter, to show our author's manner of treating the subject.

"The primitive envelope of the globe seems to have originally consisted of concentric strata of gneiss, mica-slate, and clayslate, with partial layers of semi-crystalline limestone; for such, with a few inconsiderable exceptions, constitute its rocky crust, and are spread over all its regions. These coats, however, no longer lie in layers concentric with the spheroid, but are thrown up into nearly vertical planes, and transpierced in many points by towering masses of granite and porphyry.

"On the primordial spheroid covered with its illimitable ocean, these stratiform coats lay in horizontal planes; but with the gathering together of the waters, on the emergence of the land, they were heaved up abruptly into the nearly vertical tables, in which they now universally stand. This remarkable position corresponds to the eruptive violence that caused it. From the shoulders and flanks of the stupendous granite peaks, mantles of gneiss and mica-slate depend in magnificent drapery. These schistose coverings are arranged near the summit in folds almost upright, which lower down, become sloped off with clay-slate and limestone into a gentle declivity. The coats of gneiss are often contorted into the most singular flexures of rock scenery, demonstrating a certain pliancy of texture at the instant of erection; resulting either from the moisture out of which it rose, or the softening influence of subterranean fire.

"The wood-engraving at the bottom of this page, taken from D'Aubuisson, represents the usual structure of the primi

tive mountains. It is impossible for an unbiassed mind to contemplate this sketch, given by a Wernerian geologist, without seeing its entire conformity with the eruptive mode of formation."

BOOK SECOND is entitled the Antediluvian Period, and includes all mineral formations which contain any vestiges of organic life. It is divided into five chapters, which present a succinct description of the great mineral planes, from greywacke up to the diluvial gravel. Here he has introduced, in their appropriate places, lively abstracts from Cuvier and other writers on the organic remains, found among the secondary and tertiary strata. These are illustrated by well selected wood-cuts. This portion of his work will contribute essentially to promote the popular diffusion of geological science.

The following view of the Paris basin, may be cited as an ingenious attempt to solve a geological puzzle.

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Such is a brief transcript of the admirable memoir of MM. Cuvier, and, Brogniart, on the most interesting formation hitherto explored by the joint resources of geology and physiology. It exhibits an unfading picture of the convulsions which the primeval globe suffered a few centuries prior to its close. The chalk beds of both the Paris and London basins evidently stood, at first, near the level of that ancient ocean, as may be deduced from the billowy undulations on their surface, Had they lain deep under water, the rolling of the waves, could not have chequered their face with those remarkable ridges and excavations, which still exist to indicate the cause of their origin.

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"It was about this geological epoch, that some of the great fields of basaltic-lava were poured forth from the interior of the globe, spreading over the secondary strata of chalk and sandstone, as we see exemplified in the north of Ireland,, in Scot land, and many other countries. The epoch of the covering over of the great chalk formation of Antrim with basalt, coincides with the covering of the chalk basins of Paris and the Isle of Wight, with their tertiary strata. The acts of eruptive violence which immediately clothed the submarine chalk surface of one region with an immense sheet of lava may have up heaved the chalk slightly above the level of the, sea in another district not far distant, thus converting a marine basin into an estuary of great extent, which probably comprehended at once the London, Isle of Wight, and Paris basins. For the depres sion between them that forms the bed of the English channel is very trifling in proportion to its extent of surface and is very much exceeded in depth by the large continental lakes.