and South Parts may be deemed both the Sides of the Earth.

Now 'tis well enough known to those that have look'd into the lateft Obfervations of the accurate Moderns, that tho they are wont to term the Earth a Spherical Body, without having any regard to the Inequalities that may be occafion'd therein by Mountains and Vales, yet it is not perfectly globular, but has a greater Protuberancy under the Equator, and grows continually lower or flatter towards the Poles.

Upon the Obfervation, that the Pendulum of a Clock at Caienne, near the Equator, must be 14 of a Line, or of of an Inch fhorter, to strike exactly a Second, than it was neceflary to be at Paris. Mr. Huygens, in his Treatife of Gravity, afferts, that the Earth is flatter at the Poles.

In Sir Ifaac Newton's Princip. Philof. Prop. XIX. Lib. 3 we fee the fame; as likewife in Dr. Gregory's Aftron. p. 36, and 268. and in Mr. Whifton's Pralect Phif Mathem. Prop. XCIII. Corol. 2. we find thefe Words, befides what is faid in other Places thereof; Since it is known by Obfervations and Experiments, that our Globe is actually higher at the Equator than at the Poles. In the Hiftory of the French Academy, 1700. p. 144. and in the Memoirs, p. 227. we find Obfervations taken at Lisbon and Paraiba in America, which feem exprefly to confirm the fhortening of the Pendulum in the Approach to the Equator, and confequently to prove the greater Flatnefs, of the Earth at the Poles, tho' the exact Greatnefs is fcarce to be determined by thefe Obfervations.

But that we may not be liable to the Difficulties and Objections that fhall be made against the Hypothefes ufed by fome for the Proof thereof, it is very remarkable, what is faid upon the fame Subject, in the Hiftory of the faid Academy for

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the Year 1701. p. 120. and in the Memoirs, p.237. &c. where Mr. Caffini, carrying on the Meridian of France to the Pyrenean Mountains, by order of the King, has nicely measured the length of each Degree of the fame, and found in 7 Degrees between the Parallels of Amiens and Coljure, which he has compared with each other, that the Quantity of each continually increafed as they drew nearer, to the Equinoctial, and confequently decreas'd as they approached to the Poles. So that, without contefting too ftrictly the exact and Geometrical Figure of the Earth, and without admitting any Hypothefis for a Foundation, in cafe what Mr.Caf fini has really found in each of thefe Degrees, obtains in all of 'em from the Equator to the Poles, certainly the Equator or Equinoctial, itfelf is greater than any Meridian or Circle paffing thro both the Poles And the Earth is really a Globe, but a little flattish at the Poles. The fame may be obferved by the help of Telefcopes in the Planet of Jupiter itself, and was fo done by Meffieurs Caffini and Flamftead; See Whiften's Prop. 93. and others.

Now, whether this be the Experiment of which Mr. hifton makes mention in the place abovequoted, I know not, because I do not find them added to it. This is certain, that this Author, in his Pralect. Aftron. II. Prop. II. p. 8. of the Earth, fays, that it is nearly or almoft Spherical; yet with fo little Difference, that he reckons them among thofe Trifles that are not worthy to be taken notice of in Aftronomy, becaufe the Difference which the fmall Flatnefs thereof may occafion, is in a manner infenfible.

SECT. XXIV. The Gravity of all Earthly Bodies:

I HAVE oftentimes confider'd with great Aftonifhment, that wonderful Motion which the Philofophers call Gravity or Heaviness, and by which every thing that we know upon the Earth is attracted or driven down and towards this Globe.

I fhall not here relate nor difpute the various Arguments of Philofophers about the fame; whether it is to be confider'd as accidental only, and whether it be occafion'd by the Highness of other Bodies which force the heavier downwards. This is however true, that all Corporeal Things that are known to Mankind upon this Globe, have their Gravity or Weight, not excepting the Air and the Fire, nor even that fine and pure Fire itself which has firft paffed thro' Glass: All which, according to the Discoveries of these Times, have been visibly proved by a nice Balance, to have their Weight. See Boyle de penetrabilitate vitri à ponderabilibus partibus flamma. Yea, that the pure Light itself, being collected by a Burning-Glass, may be united to other Bodies, and render them more heavy, will be fhewn hereafter in Contemplation XXIV. by the Experiments of Monfieur Hombergh.

Now how ftrongly this Gravity operates, does even appear from the Preffure of Bodies, which do otherwife feem to be without Motion. From hence it is we fee great Ships fink, and oftentimes very ftrong Floors of Houses fall in by being over-laden.

Now I ask any reasonable Perfon, whether he can believe, that ftupid and infenfible Things, which cannot produce the leaft Motion in Themfelves, are capable of observing such exact Laws, without

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without the Direction not only of a Powerful, but likewife of a Wife Being? For in cafe C be the Centre of the Earth (Tab. XV. Fig. 3.) and the Circle drawn from thence be a great Circle upon its Superficies, and the Lines F G, HI, KL, MN, that touch the said Circle, represent the Horizons of each Place; every one knows, that if a Stone, or other heavy Body, were let fall at A, it would move according to the Line A C; if at B, according to BC; at D, according to DC; and at E, according to E C: and that this is a true Pofition, is well known to thofe Pilots that have failed partly or wholly round the Earth, who must all bear Witnefs, that fuch is the Method of their Fathoming in the different Places in which they happen'd to be.

Now let the Caufe of this Gravity be fuch, as every one, according to his own Philofophical Syftem, fhall think fit; yet he must nevertheless acknowledge, that without this Property the Earth would be uninhabitable, efpecially if he comprehends what has been faid above, concerning the Weight of the Air and Water.

SECT. XXV, and XXVI. The Centre of the Earth is a Nothing.

Now, not to ask, whether any one can imagine that it comes to pafs without a wife Direction, that a Body wholly ignorant and infenfible, being placed at A, fhall move from A to C ; and being at E, from E to C, along a freight Line directly oppofite to it; and that in all Places where any Body falls down upon the Earth, it fhall always chufe the nearest and fhortest Way to the Centre thereof: Thofe who feriously contemplate this great Wonder, that all Bodies, how large and unweildy foever they be, without the least knowledge

knowledge of what they themselves are doing, will move with fo dreadful a Force towards a Mathematical Point, to a mere Ens Rationis, which has no Exiftence out of the Thoughts of him that conceives it; and (tho' it may be juftly called in Bodies, a perfect Nothing) will yet remain hanging to it; Can they, without acknowledging the Wifdom of GoD in his Holy Word, read the Expreffion made ufe of by Job, ch. xxvi. v. 7. He hangeth the Earth upon Nothing?

As great a Paradox as this may appear to be, the obdurate Atheift, if he understands any thing of the Mathematicks, muft own, that it is an undeniable Truth, as the Holy Penman has there expreffed it. Is not every thing heavy among all Earthly Bodies that have yet fallen under Humane Enquiries? Does not this Heavinefs caufe every thing to defcend towards the Centre of the Earth? Does not the whole Body of the Earth difpofe itfelf into Circular Figure about the faid Centre? And therefore in the very Words of Job, does not the Earth by fuch Gravity hang upon nothing on all Sides? Is not then the Centre a perfect Nothing in itself, and exists only in the Idea of Men? Why do we hear Euclid. Defin. I. Lib. 1. deferibe the fame thus; A Point is that which has no Parts? And to fhew that the following Mathematicians held it to be no Part of Matter, fee what Clavius fays of it in his Annotations, namely, that no Example can be given of it in material things. Thus we fee, that Whifton, in his Treatife above-mention'd, Prop. LXXXVIII. Corol. 2. fays, that the common Centre of Gravity of things in this World,being only a Mathematical Point, is plainly a Nothing. The like Teftimonies one might produce from more Mathematicians. Now if it be not material, what is it then, other than a Nothing in material Things, and a mere Notion only, that we form to ourselves

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