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SECT. LXXI. Thirdly, By the Courfe of the Planets in an Ellipfis.

BUT to cut off all Cavilling about this Difference, it may be fufficiently proved from the Property of the Curve Lines, according to which each of thefe Planets are moved, that there muft be an inceffantly directing Power that regulates their Courses, and that they cannot alone be carried forwards by any circularly moving Matter.

For the continual Experience of all Aftronomers that have fucceeded the Great Kepler, and fo frequently repeated Obfervations, have put it fufficiently out of all doubt, that the Planets are not moved in exact Circular Figures; in which Cafe it might be fuppofed, with fome appearance of Truth, that there is fuch a whirling Matter, but they are Curve Lines of quite another Property than Circles, and appear by manifold Obfervations to be Ellipfes, or oval Figures, as you fee in Tab. XXII. Fig. 5. A E DZ.

In thefe Ellipfes, as is well known to the Mathematicians, there are two Points K and S, each of which they call a Focus, or Point of Burning, from whence the fame may be defcribed by a String KES, faften'd at K and S, and by a Nail at E, which being directed by the String, describes the Circumference EDZ A, as is known to Carpenters, Joiners, and other Mechanicks.

In one of thefe Foci is plac'd the Sun S, about which the Planet is continually moving; A is the remoteft, and D the nearest Point of the Orbit to the Sun; for which Reafon likewife, A the fartheft, and D the nearest Point to the Sun, are termed by Aftronomers, the Apherlium and Perhelium.

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SECT. LXXII. Fourthly, Because their remoteft Points extend to different Parts of the Heavens.

AND that no body may imagine neither, that any ignorant Laws of Nature have any Place here in a Stream of Vortices, or whirling Matter; the adorable Creator, who alone will be acknowledged and glorified herein, has fhewn, with irrefragable Proofs, his abfolute Empire over thefe great Bodies, and likewife his wonderful Power in thofe vaft and remote Spaces; for which Purpose he has not thought fit that the Elliptical Orbits of the Planets, as A E DZ, and L R, MT, (which very much differ in Magnitude and Distance from the Sun) fhould have their Aphelia A and L extended from the Sun S to one and the fame Place of the Heavens, as B; which would have appeared more convenient to our Conceptions, and might have been used as a Principle to difcover, after this manner, a general Law of Nature, whereby we could have accounted for thefe Motions and Difpofitions in the Heavens.

But to the End that every one who contemplates thefe great Works might be certain, on the contrary, that it is only the irrefiftable Will of a fupream Director of all things that has place in this Matter, he has fo order'd the Orbits of the Planets A and Y, namely, A EDZ and YVNW, for fo many Ages, that the one feems to be entirely independant of the other; placing not only each of them in a different Plane obliquely upon the other, as we have fhewn above, but likewife caufing all the Lines proceeding from the Sun S, thro' the Aphelia or remoteft Points A and Y, to tend to different Parts of the Heavens, as B and C, altho' the faid Sun S,

with respect to which only he has made them, does fufficiently appear in the one Focus of all thefe Ellipfes The Truth of this may be seen in all the Books of the Aftronomers, and particularly the Places of the Aphelia of each in the Automaton. of Mr. Huygens, P. 441.

SECT. LXXIII. Convictions from thence...

Now after having well conceived all this, those who think it concerns them to learn God from his wonderful Works will be pleafed to use their Endeavours, first, by what has been faid, to make a true Notion of the Planetary Heavens familiar to them, and comparing one thing with another, to confider whether a Man argues without Foundation, who maintains, that the Power and Wisdom of the Great Creator fhines out more brightly here than the Skill and Contrivance of the Workman in the most curious Clock, or any other Machine whatsoever.

For, Firft, confidering the almost unconceivable Magnitude of these wandering Globes, and their Distances from the Sun, which may only and eafily be determined by the Diameters of the Earth. And, Secondly, feeing that Saturn, tho' it be diftant from the Sun at least 100,000 of the faid Diameters, according to the latest Obfervations, between every two following Points of its Orbit, is always attracted towards the Sun, notwithftanding there is not the leaft Band or Connexion between the one Body and the other. Thirdly, Finding that thefe Approaches to the Sun have place in all the Planets, tho' there is likewise no Union between any of them. Fourthly, Knowing that each of 'em performs its Courfe in a particular Plane. Fifthly, That they defcribe no Circles which we fee generated in natural Mo

tions,

tions, after different Manners, but to fhew that a particular Direction obtains here, they move in Ellipfes, or oval Figures, every whery preferving their Geometrical Properties. Sixthly, That these oval Figures are each of 'em extended lengthwife to a different Place in the ftarry Heavens. Seventhly, That their Motions have continued for many Ages in this Order, without any Confufion among each other. And, Finally, fince no body, who understands it right, can, without Amazement, observe, That these Globes of fuch an amazing Magnitude (that Jupiter is at leaft 8000 times bigger than the Earth, and the rest, excepting Mercury and Mars, which are somewhat fmaller) are either as big, or bigger, than the Earth itself, and yet all of 'em move about the Sun with so prodigious a Swiftnefs, as far exceeds that of a Cannon-Bullet.

SECT. LXXIV. The Motion of the Planets about the Sun.

Now if we reflect upon the Experiments which, befides the foregoing, have been made by the modern Aftronomers, and would be too tedious to be related here, new Wonders would occur to us at every Turn, and always adminifter fresh Occafion of acknowledging a tremendous Power, and a Direction continually exerting itself.

To say nothing therefore of the Comets, and their Courses from and to fo many different Places of this immenfurable Space, fince neither their Causes, nor the Ends for which they have been made, do yet fully appear to us: Let us once again bring before our Imagination thofe great Celestial Globes, the Planets, and confider, that in that incomprehenfible Motion with which they circulate about the Sun in their Orbits, they

likewife

likewife revolve or turn upon their own Axes from Weft to Eaft, at leaft it has been vifibly obferved already in Jupiter, Mars and Venus, and even in the Sun itself.

Thus we find (to fay nothing of the Earth, fince all Aftronomers do not agree therein) that that dreadful Globe of Fire, the Sun, turns round upon its own Axis in 25 Days; Venus in 23; Mars in 24; and the great Globe of Jupiter in 10 Hours. See Gregory's Aftronom. p. 36. As for the reft, we have not yet been able to discover any thing certain about them.

And in order to convince every one of the Dreadfulness of the Powers which exert themfelves in this Matter, we need only investigate the Swiftness wherewith thefe great Globes are carried about their respective Axes after the following fimple Manner.

For fuppofing the Earth's Diameter to be 6,538,594 French Toifes or Fathoms long, the Circumference thereof will contain 23,541,600 of the fame, fince the Diameter of a Circle Is to its Circumference, As 7 To 22, or yet nearer, As 113 To 355.

Now each Point that is upon the middle Superficies of the Earth would run so many Fathoms in 24 Hours, and consequently 2374 in one Second of an Hour.

But a Cannon-Bullet (as has been fhewn above) runs 100 of the like Fathoms in a Second.

Confequently every Point upon the Equator of the Earth revolves with much more than twice the Swiftnefs of a Cannon-Bullet.

If then, according to this Proportion, the Velocity in the Revolutions of the other Planets be meafured, and if it be fuppofed (to speak within compass) that the Diameter, and for the fame Reafon the Circumference of the Sun, is but

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