Chap. VI. ANTIENT METAPHYSICS. 417 



that the Motion of falling Bodies, here on Earth, was accelerated 

 according to that Rule, he further fuppofed, that the Body in de- 

 fcending fet out with a greater or lefs Velocity, according to the fame 

 Rule of its diftancc from the Centre. This theory could not be 

 verified by any fact or obfervation here on earth, the greatcft 

 height, from which we can let any body fall, bearing fo fmall a pro- 

 portion to the diftance from the Centre of the Earth, as not to make 

 any difference in the fdW of Bodies that could be perceived by the 

 Senfes. But, when he applied the rule to the defcent of the Moon 

 from the Tangent, which was fo much greater than the defcent of 

 any Body here on Earth, he found that it anfwered exactly. And 

 thus Sir Ifaac not only difcovered the Law of the defcent of the 

 Moon, but he completed the theory of Gravitation, v/hich Galileo 

 had only begun ; for he difcovered, firfl, that the defcending Body 

 fets out with a Velocity invcrfely as the Squares of the diftance from 

 the Centre ; and, fecondly, that it increafes in that Ratio, as well as 

 in the Ratio of the Times *. 



It is next to be confidered how this theory of Gravity, thus made 



general by Sir Ifaac and carried from the Earth to the Heavens, is 



Vol. II. G g g to 



* The reader, if he be as great an admirer of Sir Ifaac Newton as I am, will be 

 pleafed to oliferve the prugrcfs of ihe dovSlrine of Gravitation, thus completed by 

 Sir Ifaac Newton, and which, in my o, inion, is the greateft difcovery of modern 

 times, Ariftotk maintained, or, at leaft, the Schoolmen, in his name, maintained, 

 that the Velocity of falling Bodies was as their weight : And it is true that the 

 greater tlie weight or mafs, the greater the force required to move the Body. From 

 thence they may have inferred, that, as the Force was greater, fo was the Velocity: 

 And this ib true of the fame Body, or two Bodies of equal Mafs. But, as I have ob- 

 fervcd in the preceding Note, it will not apply to two Bodies of different Maflesj 

 for there the greater Body maybe moved by the greater Force, and yet the Velocity 

 of both Bodies be the fame. The fa£l truly is, that every particle of Body, great or 

 fmall, is drawn towards the Earth with the fame Velocity and with the fame Force, 

 if we fuppofe all the particles to be of the fame Mafs. Now, the more of thefe par- 

 ticles there are, the more of thefe Forces there muft be to make the Body defceiid. 

 There muft, therefore, be a greater Moving Force applied to the greater Body ; and, 

 confequently, its Moment may be greater but not its Velocity, the Moment being 



compofed 



