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idea of finite space will not serve his hypothesis, for then only one mass could have been formed. He must resort to infinite space. Then in the particles diffused throughout it he must deny equilibrium,—for the distribution of matter in an equal poise throughout infinite space, must either have been owing to the voluntary agency of some almighty power, or it must have been eternal. To resort to the former is to admit a Creator, and he indeed, (whether the space were finite or infinite,) might so balance the particles of matter as to form a temporary chaos, prior to the forms and arrangement presently existing. If again the equal distribution of matter was eternal, it would have remained to eternity ; the particles would never have convened without the interference of some cause beginning to act as it had never acted before,—that is, without the voluntary agency of some external Power.
Shall then the idea of infinite space be retained, and that of equilibrium among the particles of matter be denied, in order to account for the formation of different masses ?—the suppo sition is both inadmissible, and still fails to explain the present structure of the universe.
First, it is inadmissible, for if matter not being equally diffused coalesced into masses throughout infinite space, these masses must have been infinite in number, and as they must at the same time have been fewer than the original particles, it would follow that of two numbers, both infinite, the one might be less than the other, which is absurd.—But to pass this together with the idea of an infinite space filled with particles, or atoms, each divisible ad infinilum ! -the consummation of the argument is,
Secondly, That the hypothesis, whatever justice be done it, and howsoever much be conceded in its favour, still fails to account for the present structure of the universe. Matter unequally disposed through infinite space would convene into globular masses, but 1st, No law of attraction would " divide it into two sorts, and make that part of it which is fit for composing a lucid body fall down into one mass, so as to constitute a sun, while the rest should coalesce into opaque bodies."
2. No law, or essential property of matter, would make the lucid bodies larger than all the opaque ones around them, fit to occupy the centre of their respective systems, or place them there."
3. The very laws of attraction, chemical or physical, would nave prevented the existence of such a system as we now sec. Chemical attractions, unless the subjects of them had cxisted
in a diversity of kind among the diffused particles, would never have been called into being or operation ; and on the other supposition would have interfered with the attraction of gravitation during the time of concourse, producing explosions, and changing in many imstances the gravity of the descending particles so as to have long retarded the conglobation, if they had not occasioned absolute and endless confusion.*
IX. Motion in the different departments of the universe, could neither be eternal nor self-produced, and must therefore indicate a Great First Cause.
If matter be not eternal, much less motion which is but its adjunct. But supposing the eternity of matter, motion is not essential to it, since it may be produced or destroyed at the pleasure of free agents, who have no control over the essential properties of matter; and conceding not only the eternity of matter, but even of the present form of the universe, still the phenomena of motion in the different systems of which it is composed, must be traced to an exterior cause,--the impulse of a moving agent adequate to the effect, and distinct from the subject moved.
• It is to be regretted that the Letters of Sir Isaac Newton, from which these extracts are given, labour under considerable disadvantage from a certain degree of confusion, which has perhaps prevented their obtaining that notice and respect, to which not only the name of the author, but the force of his reasoning are entitled. He had set out in his replies to Dr. Bentley's queries, with the alternative only of finite and infinite space, and though he evidently took for granted a want of equilibrium, in reasoning on the diffusion of matter throughout finite space, he had inadvertently supposed it "evenly spread” throughout infinite space, and affirmed that even in this case it would coalesce into distinct masses. On reconsidering the subject be stated in his second letter that " when he said matter evenly spread throughout all space would convene into one or more great masses," he understood it “of matter not resting in an accurate poise," that is not evenly spread. An attempt bas been made to remove the confusion which this inadvertency occasioned, and to reduce the argument to order, by transferring part of his tirst letter to the proper stage to which the argument is brought in the third, and inserting such steps as were wanting to complete the process of induction. The very apo. logy which Newton has made for his inadvertency, deserves our attention. " The hypothesis of deriving the frame of the world by mechanical principles from matter evenly spread through the heavens being inconsistent with my system, I had considered it very little before your letter put me upon it, and therefore trouble you with a line or two more about it,” &c.
For a confutation of the idea that the world might be formed by vortices, cr by the fortuitous concourse of atoms, the reader who deems it necessary, is referred to Bentley's Sermons at Boyle's Lecture, p. 248 and 265.
There are four ways in which motion may be conceived to arise; from chemical action from some of the auræ, magnetic, galvanic or electric,—from gravitation,—or from impulse.i. Chemical action could have no place in the original formation of the worlds, since the atoms or monads must have been simple and diffused, scattered at astonishing distances from each other. Contact, collision, or mixture, is requisite to the production of motion by chemical action ; and all these imply previous motion not accounted for by the supposed process. Then the result would not have been, the formation of bodies in all respects similar to those now revolving around their centres, nor the origination of such motion as presents itself in the course of the planets, but merely some species of fermentation, combustion, or other change of the subject acted upon ; which, again, could not have been permanent, since the materials would either have been dissipated or converted into a new substance equally inert with that in which the motion was first excited. Let us even conceive with Darwin, who has laboured to support the hypothesis, that an enormous central mass was split by chemical action, and that by successive explosions the planets, of which our system is composed, were thrown out to their respective distances, according to their specific gravities, still, (to say nothing of the difference of density which remains unexplained by the hypothesis,) this projectile force could never have originated the motion by which they are guided and preserved in their courses. 2. Of the aura, it may be doubted whether magnetism acts beyond the surface of the globe, or has any existence in other orbs; but neither the laws by which it operates, nor those of electricity and galvanism, have the smallest relation to the motions of the heavenly bodies, not even of comets, which some suppose highly electric, but on the contrary tend rather to retard, suspend, or disturb them. 3. We must therefore resort to gravitation, and consider whether this, without the fourth mentioned source of motion, an original impulse be sufficient to account for them.
In general we may remark that since gravitation may regulate motions which it cannot produce, the adaptation of the subjects of these motions in density, distance, &c. to the laws of gravitation will by no means prove that their motion proceeded from it, but rather that they were constructed and arranged by some great Intelligent Agent, who designed them to be regulated by the laws of gravitation, whether it be deemed a principle essential to matter, or the result of voluntary power. But not to anticipate,
1. We have already seen that if the particles of matter were originally diffused in equal poise, they would have remained in that state by the power of universal attraetion for ever, unless some other power had interfered. The only other alternative, that the particles were not diffused in equal poise, must be absurd on the supposition that gravity is essential, for then matter must have existed in mass from eternity, and without the interference of some adequate agent could never have been diffused. But granting its unequal diffusion, still by the law of gravitation it must have coalesced, and as soon as the coalescence had taken place, whether into one or many masses, all the motion generated by gravitation must thenceforward have ceased.
2. Admitting that the planets had disposed themselves at their
present distances, still the transverse motion by which they are impelled in tangents to their orbits, could not possibly arise from gravitation, which ever attraets them to the centre. Wherever they were formed, whether above or below or in the very orbits in which they presently revolve, they must have descended by the power of gravity, and continued their descent till they had fallen down upon the sàn, unless some other power had turned them aside into their respective orbits with a horizontal impulse sufficient to counteract but not destroy the force of the central attraction.*
3. Had the velocities of the several planets been greater or less than they are now, at the same distances from the sun, or had their distances or the quantity of matter in the centre, and consequently its attractive power, been greater or less than they are, with the same velocitics,—they would not have revolved in concentric circles, but have moved in hyperbolas or in ellipses very ecéentrie. The same may be said of the
Gravitation would have prevented the planets from occupying the place which they hold in relation to their centres, “ without the interference of a divine arm to impress them according to the tangents of their orbs.” SIR Isaac NEWTON'S Letters. Let. 3.
“ It is the compound motion which arises from gravitation and projection, that describes the present revolutions of the primary planets about the sun, and of the secondary (or moons) about the primary, gravity prohibiting that they cannot recede from the centres of their motions, and the transverse impulse withholding that they cannot approach them. This last can only be ascribed to an omnipotent arm.” BENTLEY's Confutation of Atheism.
The centrifugal force has no application to the motions of the planets, though supposed by some to account for the figure of the earth. It merely denotes the tendency of the particles of a fluid or semi-fluid body, spinning on its axis, to fly off from the centre, and therefore supposes a mass, and that mass already in motion,
secondary planets, with regard to their distances from the centres of their orbs and the quantity of matter in the central bodies.* To produce the present effect, therefore, not only an impulse beyond the sphere of gravitation and all natural causes, but a determinate impulse was requisite,--such as might give to the moved bodies a velocity proportioned to their distances from the centre and the quantity of central matter.
This must be ascribed to a cause, at once Intelligent and Omnipotent. And so must be,
4. The rapid diurnal rotation of the primary planets on their axes. T'hat this motion is neither the result of gravitation, nor of a whirl produced by explosion, is evident from its having no place in the moon, which always presents the same face or hemisphere to our world, and also from the different degrees of its velocity in the several planets, which, though invariable, clearly depend upon no law of proportion with regard to size, density, or distance.t.
5. With respect to gravitation itself, it has been demonstrated by Newton,—that every particle of matter in the uni
• BENTLEY'S Confutation.
+ Newton has shown in his second letter that “ the diurnal rotations of the planets could not be derived from gravity, but required a divine arm to impress them." BUFFON supposes that the planets were struck off from the sun's surface by the impact of a large comet, which might occasion both their annual revolution and diurnal rotation ; but he forgot that comets are connected with our system as a sort of planets themselves, which move in very eccentric orbits, and that therefore it might be asked what had previously struck off the comets from the body of the sun, and how came they to want the rotatory motion ? Besides, the formation of the secondary planets would still remain to be explained, with the difference between them and their primaries. The impact of a comet, instead of separating moons, would probably have destroyed the planet on which it struck. DARWIN, while he discards this hypothesis, conceives that the planets were ejected from the sun by explosion, and attempts to account for their motions on the principle, that “ they must have parted from the sun's surface with the velocity with which that surface was moving, and with the velocity acquired by the explosion,” adding that“ as their diurnal revolutions would depend on one side of the exploded matter adhering more than the other, at the time it was torn off by the explosion, so these would differ in the different planets, and not bear any proportion to their annual periods." (Bot. Gar. vol. i. note xv.) In this hypothesis, however, two previous motions are assumed,—a progressive motion of the sun round some distant centre, and a rotation of his orb on its axis. What was the cause of these? They are motions of the same kind with those of the planets, and if they were absolutely requisite to produce the latter, similar motions must have been requisite to produce them; and since the previous motions would still be unexplained though we should go on ad infinitum with a series of explosions of still larger and larger central masses, to avoid the absurdity, we may as well at once recognise a great First Cause exterior to matter, and independant on motion.