the solar system altogether," says Whewell, "the regu→ larity of its structure is very remarkable. The diagram, which represents the orbits of the planets, might have consisted of a number of ovals, narrow, and wide in all degrees, intersecting and interfering with each other, in all directions. The diagram does consist, as all who have opened a book of astronomy know, of a set of figures, which appear, at first sight, concentric circles, and which are very nearly so; no where approaching to any crossing or interfering, except in the case of the small planets, already noticed as irregular. No one, looking at this common diagram, can believe that the orbits were made to be so nearly circles by chance, any more than he can believe that a target, such as archers are accustomed to shoot at, was painted in concentric circles les by the accidental dashes of a brush in the hands of a blind man

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Another peculiarity in the motions of the planets, is, that they are all in the same direction, and nearly in the same plane. It is quite evident, that, had chance originated these motions, they might, and probably would, have moved round the sun, both as to direction, and as to the plane of their orbit, in very different ways. Now, to those who are acquainted with the properties of the law of attraction, it will appear evident, that a most im portant object is served by the arrangement which actually subsists. Let it be observed, that such is the extraordinary nature of this law, that every particle of matter attracts, and is attracted by every other particle, the power, of course, being greater, in proportion to the quantity of each mass, and its nearness. The conse-· quence of this is, that not only does the great central mass attract the smaller bodies, so as to cause them to revolve round it, but each of these smaller bodies also attracts the others; and this mutual attraction, which, it is easy to perceive, must be of a very complicated nature, and may produce the most extensive effects, reWhewell's Bridgewater Treatise, p. 156. T

quires to be nicely adjusted, in order to preserve the stability of the system. If the numerous globes, of which our system is composed, were to move in their respective orbits, without any such adjustment, our system would be far indeed from being stable. The disturbing forces, which might only be trifling, when a year, or even an age, was considered, might, in a long series of ages, accumulate to such an amount, as totally to disorganize and subvert the whole frame. 457975 1

Nor is this a mere gratuitous hypothesis. Astronomers have actually discovered, in our solar system, an apparent tendency to derangement. Changes have been taking place, owing to the cause just mentioned, which, at first sight, appear to be of an alarming nature. The eccentricity of the earth's orbit has been gradually diminishing; the moon has been approaching nearer the earth, and accelerating her motion; and the obliquity of the ecliptic has been diminishing.These changes have been going on, from the period of the first scientific observations, to the present day, and are still in progress. Are they to continue without end? If so, the present system of things is tending to destruction.

This question has, by an amazing effort of calculation, been satisfactorily answered. Aided by the mathematical investigations of ages, two celebrated French philo sophers, Lagrange and Laplace, have solved the problem, and have demonstrated, that "the planetary system will only oscillate about a mean state, and will never deviate from it, except by a very small quantity."* This remarkable result depends on these three conditions, that the orbits of the planets are nearly circular; that these orbits are nearly in the same plane; and that they all move in the same direction. alt tex

Had any one of these conditions been different, the equilibrium of the system would not have been maintained; the tendencies to derangement would not have been counteracted, but, on the contrary, year after year, * Laplace, Expos. du Syst. du Monde, p. 441.

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would have been accelerated by accumulation and, sooner or later, the whole fabric would have broken up, and been dissolved by its own inherent defect.orolt tat It is unnecessary to enter into any argument, to show that the combination of sthét various arrangements al+ luded to, could not have occurred without design that the adjustment is that of an Intelligent Cause, and that taffords the clearest proof of consummate and adorable wisdom ob odt to ydtrow „dtørt e nismer lite lliw ei redto Is to doidw .botqobs zow nely gift tilt noit gaiduteib tortavo bits gomeled of botelwolso tend vory bluoroitprobiertos rodio dorodile p979 „299707 FOURTH WEEK-SATURDAY. ei tl Ism1519 90 of bзbism Ton 28 M191272 9dt tødt Bulb STARRY HEAVENS,RESISTING MEDIUM aids VI.THE ewotend doiw bus etes ti olid motera edt to quidrow bosWeghave seen, in the case of the planets, including also their satellites, that Supreme Wisdom has sobalanced our system, that the disturbing forces, to which it is subjected by the mutual attraction of the heavenly bodies, will, in consequence of simple but selected tarrangements, in the course of ages, correct themselves, so as never to threaten any violent change from such-mechanical causes, so far, at least, as the power of attraction is concerned. This is highly satisfactory, as a demonstration against the atheistical doctrine, which would exclude from the universe the operation of a Designing eCausedivIt does not, however, prove the absolute perImanency of the system, and we know, from the " more sure word of prophecy," that it is not destinedatozdast sfor ever19b9qobni tud oldata ed of 2m992 mu boThere is, vindeed, another element to be taken into consideration, which the French philosophers, already alluded to, have overlooked or rejected, but which bears directly upon the question of inherent stability, I mean the question regarding a resisting medium. All their ¿calculations have been founded on the two simple powers hof attraction and inertia, under the supposition that these *powers acted in empty space, without the existence of

any impeding force. If it be found, therefore, thatva resisting medium actually exists in the systemp that is, that there is some fluido matter, however rare, in which the celestial bodies move, then this one fact will overturn the conclusion as to the absolute and inherent permanency of the present system of things so far as mechanical powers are concerned. to Nor will this discovery invalidate the reasoning in the preceding paper; for it will still remain a truth, worthy of the deepest admiration, that the plan was adopted, which, of all others, is best calculated to balance and counteract disturbing should prove

forces, even, althou not intended

that the system was to be eternal. It is this principle which secures the equal and salutary working of the system, while it lasts, and which bestows upon it properties suited for the habitation of organized existences, during that period gland this is the whole extent of the view for which we have been contending.

n

[Is there, then, a resisting medium,→→a fluid inʊwhich our system floats Agoriare our planetary spheres whebled in empty space?The diffusion of light throughout the universe, might, of itself, form a powerful argument for the existence of such a medium, of whatever theory its properties are accounted for.ei Light is either an emanation from the great central body, and then that emanation must be somethingsmaterial peor vitais an exciting cause of vibratory motion grand, in that case, the vibrations must apparently be conveyed through some material substanberinbeither case, the theory of an absolutervacuum seems to be untenable. But, independent of this view, somes facts have been very recently discovered, which cannot well be accounted for, but on the supposietion of adresisting medium. I allude to certain circumstances occurring in the motion of one of the comets belonging to our solar system, to which the importance of Encke's observations have justly caused that astronomer's name to be attached. The revolution of this body round the sun, is found to be completed in a period of about

three years and four months, while its orbit is so eccentric and elongated, that it is more than ten times nearer the sun in one part of its course, than in another. The materials of which it is composed, seem to be exceedingly thin and transparent, so much so, indeed, that the stars may be seen through the most condensed part of its nucleus, without any apparent diminution of their brilliancy. In 1786, this comet was first observed; but it was not till 1822, that its periods were accurately determined; and then Encke, on comparing the calculated with the observed places, perceived a difference, which he attributed to the effect of a resisting medium. It was again the subject of conversation în 1825, in 1828, and still more recently; and the conclusion has become general, that the obvious and constant disturbance of its course, arises from no other cause than that of its being affected by its motion in an etherial fluid.

This fluid, however, must be of inconceivable rarity, and would probably not produce any apparent effect in its velocity, were it not from the small quantity of matter contained in the vapoury sphere, which, as will easily be perceived, must increase the power of resistance of the medium through which it moves. Light and loose, however, as the body is, it has been found to be acted on by the solar and planetary attraction, in the same manner with the other heavenly bodies; and the result having been accurately calculated, what Sir J. Herschel calls a residual phenomenon, has been discovered, which has given rise to the inference of a resisting medium.

The effect, however, though something very discernible, is yet but trifling; and, what may appear strange, this retardation of the motion, causes the body to perform its revolutions round the sun more quickly. The reason is, that the increasing slowness of the motion has the effect of augmenting the relative power of the sun's attraction, thus drawing the comet nearer to himself, and shortening its orbit. Within the last fifty years, in which its course has been observed, it has been found,