374 A NT I EN T METAPHYSICS. Book V. 



will furely not account for the renewal of the Motion, after it has 

 ceafed, hut another Impulfe will be nccefiary, and another as often 

 as the ftone is taken up and falls again : And, fuppofe all thefe re- 

 peated Impulfes could be admitted, I afk the fame queftion that I 

 did with refpedl to Trufion, "What Body can be fuppofed to give an 

 Impulfe that will make a rock of an hundred tons weight tumble 



down from the top of a mountain ? But it is fpending time to na 



purpofe, and, I think, abufing the patience of the reader, to ufe more 

 words to refute what, I think, may be called the Dreams of fick 

 men ; by which, if they mean any thing, they mean no more than 

 to get free of Mind, altogether, in the operations of Nature. And, 

 in converfation with fuch men, I have difcovered that they did not 

 really believe in fuch Fluids, or Impelling Bodies, but believed that 

 Body moves itfelf ; for this, as I have faid, is truly the only hypo^- 

 thefis upon which Materialifm can be defended. 



Before I leave Gravitation, it will be proper to obferve, that, as 

 there is nothing in Nature without rule or meafure, fo the rule of the 

 Motion of defcending Bodies has been difcovered in modern times ; 

 and I think it was a very great difcovery. The antients, no doubt, 

 knew, as well as v/e do, (and, indeed, it is obvious to common ob- 

 fcrvation), that a Body, in defcending, accelerates its Motion ; but 

 it was not known, till the time of Galileo, by what rule this accele- 

 ration was : He firft difcovered that it was as the times of the fall ; 

 fo that, in a double time, the Body, acquires a double velocity : The 

 confequence of which is, that the fpace the Body goes through is as 

 the fquares of the times ; fo that, in a double time, the Body has 

 gone through a quadruple fpace. 



But, though Gravitation be not produced by Impulfe, there are 

 certainly other Motions on this Earth, both from Nature and Art, 

 that are fo produced: But, as to fuch natural Motions, as Magnetifm, 

 Eledricity, and the Attradions and Rcpulfions of the fmall particles 



of 



