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Earth would constantly dilate by every E. pressing on the superincument particle was admitted—that as the globe distended the quantity of vacuity within the interior would increase—and that after the Earth had attained to the magnitude of Jupiter, there would exist within it at least a hundred and twenty times more vacuity than matter;-having obtained these data, they now argued as to the probable effects that would be produc'ed on the globe by the constant pressure of all the particles in an opposite direction, and since they had found that a quantity of vacuum, equal to a hundred and twenty times the magnitude of the Earth, before it was subjected to the operation of the expansive force, was now contained within it, they had no difficulty in admitting that the particles would take a retrograde movement, and that the globe would consequently suffer a diminution of diameter. It was however a problem long and keenly agitated amongst them, to determine the precise state of condensity of the Earth at which the mobility of the particles would be arrested; this was found to be a problem of very difficult solution, and it was not till after much contention and varied discussion that they arrived at the plain and natural conclusion, that so long as vacuities existed within the interior of the Earth, the motion of the particles downwards would never cease; and as they found that the force which counteracts the force of gravity does not operate to a great depth below the surface of any one of the planets, they thus proved that the densities of all of them must still be constantly increasing. No sooner was the discovery of this i. law announced to the phiosophers of every country, than they began to apply it to the solution of those phenomena which till then in several physical sciences had remained problematical. First the spheroidal form of the Earth received a ready and certain explication, and then the important fact was obtained, that the mean density of the Earth, from the centre to the poles, is greater than from the centre to the equator; and this fact suggested a new and plausible theory as to the cause of the polarity of the magnet—those numerous and wonderful discoveries which were evolved by the compression of mixtures,

and the subsequent expression of some of the substances of which they were composed were also due, though less directly, to the discovery of this extraordinary law; but of all the sciences, Geology and Cosmogony were certainly the most indebted to its evolution. In geology it accounted satisfactorily, First, Why strata, which were originally horizontal in their position, are now inclined to the horizon. Thus, as a plant increases in density, it diminishes in magnitude; and since it is constantly increasing in density, it is constantly diminishing in magnitude, this globe has therefore suffered a diminution of magnitude since the strata were deposited which everywhere encompass it ; and, therefore, since these strata at their formation would form the circumference of a larger globe, and are now circumscribing the nucleus of a less, they would, if soft, suffer bendings and inflections while accommodating themselves to a globe constantly diminishing in magnitude; and, if indurated, they would break asunder, and assume a position somewhat inclined to the horizon, and as the globe diminished more and more in magnitude, the strata would approach more and more toward a verticle position. Second, Why strata deviate the more from the horizontal position as they are the more ancient. As this globe has constantly diminished in magnitude, then the more we recede from the present period, the greater will be its magnitude, and consequently the more ancient the strata, the greater would be the globe on which they were deposited. . Since, therefore, strata, according to their seniority, would, when deposited, form as it were the circumference of a larger globe, and they are now all investing the same nucleus, and that the nucleus of a less, it is evident that the strata last formed would require to shift less from their original horizontal position, in order to accommodate themselves to the present magnitude of the globe than strata of a prior formation; that therefore the more ancient the strata, the more must they be displaced from their first position; the primitive strata must have therefore assumed a posture more highly inclined to the horizon than those of a subsequent formation. Third, Why strata, which were ori

ginally soft, are now consolidated; and why in general they are more indurated as they are the more ancient. The force which consolidates the Earth, must also be equal to the consolidation of the strata near the surface, where it acts with so much intensity; and since the solidity of the globe is constantly increasing, the consolidation of the strata must likewise be in constant operation ; those strata, therefore, which have been the longer subjected to the consolidating cause must be the more indurated, i.e. strata must be the more indurated according to their seniority. It must however be remarked, that the hardening of the strata is not altogether effected by the perpendicular pressure of the particles; there is besides a constant lateral pressure, arising from the circumference of the globe being in a state of constant decrease; and, by the cooperation of these two forces, the fluid which every stratum contains after its deposition must be ultimately expressed. Fourth, Why bendings and inflections are more frequent in strata according to their seniority. As the force which consolidates the Earth acts nearly with the same intensity, whatever may be its density, it is evident that the magnitude of the globe must diminish the faster in proportion as the Earth is less dense. Those strata, then, which were deposited when the density of the Earth was not so great, would not preserve their level position so long as those

which were deposited when the density of the Earth was greater; since, then, the more we recede; from the present period, the density of the globe is always the less, strata would therefore, according to their seniority, preserve their horizontal position for a shorter period; they would consequently be the less consolidated while shifting from that position, as they had not been so long subjected to the operation of the consolidating cause, they would therefore, according to their seniority, be more pliant while shifting from that position; wherefore, bendings and inflections must be more frequent in strata according to their seniority. The shifting of the strata, while accommodating themselves to a globe diminishing in magnitude, accounted for earthquakes. The latent heat which exists below the surface of the Earth, and which must from time to time be expressed as the globe gets more indurated, was found to be the primary agent in the production of a volcano, and as there is a greater pressure at the time that the strata are turning to a more vertical position, it accounted for the fact of the earthquake and volcano generally accompanying each other. It was also found, that the substance of a vein was originally diffused throughout the strata which include the vein, and had been expressed from the strata after the formation of the fissure which now contains it. C. C. (To be continued.)

SOME EFFECTS OF AN ExCESSIVE APPLICATION TO THE STUDY OF PHYSICAL SCIENCE CONSIDERED.

It seems a fit subject for the curiosity of an age to inquire into the effects upon its character of its own peculiar pursuits; unless it may be thought, that, with a people, as in the case of an individual, too much curiosity of self-examination may both enfeeble and mislead the mind. Yet to a

ple, as well as to an individual, there must be a measure of self-examination that is both justifiable and salutary; and we conceive, that the questioning of those opinions, upon which a whole generation is disposed to act with implicit confidence, and something like the ardour of passion, may fall within this reasonable measure.

The age to which we belong has pursued, with activity and success unknown before, the investigations of physical science; and with this spirit of inquiry there has prevailed also a persuasion, that the knowledge thus acquired to the human mind was of high importance, not only for the owers which it added to human art, ut for its direct influence on the faculties and character of the mind. Its influence may be beneficial, but it may easily be over-rated. We believe, too, it is in danger to exceed its just limits. The effect upon the mind, of application to physical science, will vary with the character of science itself. For science may be exceedingly speculative, or it may rest almost entirely in a sort of practical demonstration. In our own country, we apehend, for the last half century, it }. borne this last character. The science which has chiefly flourished amongst us, which may be said almost displacing all others, to overspread the land, the science of the intimate analysis of natural bodies, perhaps by its ready application to the arts of life, o by its own inherent tendency, as eminently assumed this practical character. Of the more ancient state of the science, of the researches, by such analysis, into the properties and powers of nature, which were pursued with such avidity of hope, and such intense application of thought by the elder alchemists, we seem now to know little or nothing. Their specific results are scarcely regarded, and their effect upon the minds of those inquirers, and through them more generally upon society, seems still more remote from touching us. A chemistry of our own, a new created science, has sprung up to our age, eclipsing by its splendour, the dim and feeble lights of preceding time; and still more, by the importance and magnitude of its practical consequences, occupying the minds, and giving occupation to the lives, not only of men educated to science, but of numbers with whom such results alone could give it interest and favour. Of that chemistry we would venture to speak; and of whatever other sciences, that lending themselves in like manner to the practical uses of life, have obtained an importance in the national mind, distinct from, if not exceeding, the pure interest of scientific inquiry. The spirit which originally impels men to the investigation of nature, seems to arise, not merely out of their intellectual capacity and dispositions, but to hold a yet deeper seat in imagination. Wonder and fear are the feelings with which, in the more primitive states of society, men approach to such inquiries. o can perceive a mysterious darkness shrouding the secrets of nature; and that ungovernable curiosity which to the vulgar has seemed impiety, may have been felt as questionable daring, by the minds that obeyed its impulse. The awe of that mystery lay upon their souls;

and the deep delight with which they proved their power at times to lift the veil, was mingled with trepidation. We rank these feelings with the superstitions that are gone. But it would be much to say, that they were altogether the work of superstition. The feelings which superstition seizes on, and magnifies, may be legitimate in our nature; and we are not to conclude, because we know no such awe, we who are familiar with all speculation, we on whose childhood the lights of knowledge are showered before our understanding is even awake to receive them—that therefore there is nothing but fantasy and illusion in those strong and agitating impressions which have accompanied heretofore the investigation of the secrets of nature. If Maclaurin has said that he never read the questions of Sir Isaac Newton without feeling his flesh creep, if Mallebranche, when he first opened a volume of Descartes, found his eyes burst into tears and the book drop from his hands, we may be assured that there are strong feelings and strange emotions annexed in the constitution of our nature, to such high investigations. And if we recognize them no longer in ourselves, we may be rather led to apprehend, that by some ill-husbanding of our own we have thrown away a power we were endowed with, than to exult in our liberation from prejudice and error which hung upon the faculties of less enlightened inquirers. I conceive, that in the original impulse which bent the mind of men to these speculations, which urged them to explore the powers and the secrets of nature, there was in fact much more of mysterious imagination, and of deep unwonted emotion, than of mere intellectual gratification. And I suspect that the language in which Lucretius has described the state of the mind borne in the consciousness of its power into unknown worlds, me quaedam divina voluptas Percipit, atque HoRRoR does more truly discover to us that natural conformation of our minds which calls us to such speculations, than any thing which now appears in our own pursuit of them. The blending of the knowledge of Nature by the earliest ages with their mythology, and somewhat later, with their most solemn and impassioned poetry,

md the language in which the ancient ts of the most cultivated times speak of the feelings and faculties that belong to philosophy, all testify to the same purpose. Nor should we have much difficulty in believing, that the power in men's minds, which could suspend the strong passions of life, which in fierce and turbulent ages, in the midst of ardent and perilous contention, could turn them to lonely thought, and to the still contemplation of nature, was sprung from a deeper source, as it held them with a stronger controul, than is known to the philosophy of an age like ours. These powerful feelings, whatever they may have been, pass away; and there remains to an age like our own, as the impulse to the same pursuitsintellectual pleasure—the love of truth —and the confidence in important results of investigation, extending the dominion of man over nature. If now we should attempt to compare the results of these two states of science, it may appear, that the tendency of inquiry pursued under those strong original impulses, was not so much to extend the actual dominion of science, as to bring back to the mind its own action resulting upon itself. The intellectual powers, filled with energetic life by the passion that incited and sustained their exertion, grew to their height of native strength; and at the same time, being blended in their strong action with sensibility and wonder, and thus let into the moral nature, they turned on it their own strength, and exalted the individual character of the man himself. Hence we may read in the history of early ages, examples of high moral powers produced by the love of knowledge; a proud and lofty strength, an exaltation and fortitude of character growing out of the speculative faculties, which gave to the contemplative philosopher his equal place, among the stern and gigantic progeny of the times. The reverence of a dark age was around him; and if he could dissipate neither their darkness nor his own, yet he upheld in the midst of their violent and agitated life the veneration of intellect. He felt it deeply in himself—he impressed it in awe upon others—and transmitted in unimpaired vigour the germ of intellectual life, to the ages in which its own sun should arise upon it, to call it forth into beauty.

The beneficial influence of the study of physical knowledge, pursued in the spirit of wonder and imagination, is chiefly to be looked for in this moral effect; in the high and powerful place which it concurred to assign to the faculties of intellect in the individual mind in the living man,—Knowledge itself, it is probable that it cften darkened. It could not be otherwise. For, carrying upon scanty materials of thought great and eager force of conception, it must needs rear up to itself at once a vast edifice of seeming knowledge, which, disproportionate as it was to the realities upon which it was constructed, could only be illusion. When these feelings are passed away, if ever an era of science should arrive, in which the value of such knowledge is appreciated merely by the power which it gives to man in his dominion over nature for the purposes of lifethen these results are reversed. Truth is discovered; for only the most exact truth satisfies the purpose of inquiry. But the intellectual mind is lowered. It is made a servant to life. No longer united with imagination and sensibility, no longer carried back into itself, from its excursion amidst material knowledge, with augmented sense of its own sublimity of power—it cannot bring back into the man himself a moral exaltation—but it accustoms him to deduce a value to his own powers from the purposes in which i. are employed. It teaches him at last to feel, that he with his faculties is important, only because the objects of his knowledge are more important than him.# But before science can fall into such degradation, if it should ever fall into it, it passes through an intermediate and a better state:—when intellectual pleasure, and the love of truth, are the incitement to its cultivation. This is the epoch, when its beneficial influences appear the most unquestionable; when its effects seem necessarily the most pure. Yet it seems possible, that even these effects may be over-rated, and may be carried to excess. Intellectual pleasure is a just motive to the pursuit of science; for we have a right to the natural enjoyment of all our faculties. It is salutary too, as all natural and grateful activity induces

health and vigour.—But we over-rate

the value of intellectual pleasure, when we conceive any intellectual end to be the chief purpose of science; which we easily do from its intellectual nature; forgetting that its highest end is to serve a moral utility. We overrate it still more unduly, when we esteem in such pursuits our own enjoyment, merely withdrawing ourselves from consideration of the service which all our faculties are bound to render. We indulge it in excess, when the interest of the knowledge we attain, is less than the pleasure of our own intellectual activity. The love of truth, is the purest of all the purposes of science. It ennobles the faculties it employs, and carries its unconscious virtue into the whole moral being. The study of even natural truth, has this high and beneficial character; but the study of natural truth, is in some respects liable to excess, and to over-estimation. For it has a tendency to raise itself up into competition with moral truth; not in those minds, perhaps, which pursue it in purity, and simplicity, but in all those which pursue it in the pride of their power, and in all those which are carried to it by a contagious ardour of opinion. It may be

said, especially, that when the study

of physical science becomes on any account the favourite and general pursuit of an age, it tends strongly and directly to obscure moral truth. The subjects of moral knowledge, though of all the most real to the mind, are to a judgment immersed in the objects of sense, shadowy and unsubstantial. The mind, incorporated as it is, in life, with matter, is prone to forget its own independent nature. It withdraws itself with effort from sense, and easily yields to its solicitings. Material science flatters this declension of the spirit; while in the faculties it employs, it seems to allow the mind the privileges of its higher nature, and yet calls it down into the sphere of sense. The spirit, prone to delusion, engages without suspicion, in that knowledge, in which it is yet intellectual, while it is given over to matter: it attains moreover, such easy satisfaction,--it finds so soon a firm resting-place in the knowledge which is built of such solid materials; and conceives in its system of science, dimension and structure like that of the world itself, which its system presumes to embrace and comprehend. It is

not to be wondered, if with this seductive aid to natural inclination, this strength grafted on natural infirmity, difficulties should grow tomoral science, and if the world which it explores, should diminishin comparison into narrow compass, and fade into shadows. There is an injury to moral contemplation arising also from the influence of these studies, on the character of the intellectual faculties. The faculties, exercised in the investigations of physical science, attain to a new and unknown precision in their action; a result of great general importance, if it could be kept merely subordinate; but which is in danger, if it draws to itself excessive estimation, of deceiving the mind into too low an estimate of its other most important faculties. The absolute necessity of this intellectual exactness, in material knowledge and arts, and the overwhelming magnitude of the results that are thus built, it may be said, upon that quality alone,

concur to generate in the mind a scorn,

a slight regard, at least, of all those faculties, in which this strongly defined action is wanting. Imagination, sensibility, passion, the sources of moral knowledge, are lowered in the scale of esteem : not upon a consideration of their actual place in human nature, or of their influence upon lifebut because their action, so often obscure, troubled, and indefinite, wants that virtue of precision, by which the faculties merely intellectual have achieved their stupendous works, have subjected the laws of mature to their knowledge, and her powers to their sway. These observations, as far as they are true, apply to the whole circle of physical science. We would add a single observation, on that particular science, of which we have more peculiarly spoken, that science, which in the laboratories of the alchemists was perhaps the most mysterious and full of imagination of all the sciences, and which is become, in the hands of modern chemists, of all the most material in its ordinary state, the most separated from mind. For the intellectual cultivation yielded by any science, arises from the intellectual interest with which it is pursued. As long as the materials that are subjected to the understanding invite the faculties to exertion, as long as awakened intelligence is discovering its own paths among

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