THE NEWTONIAN PHILOi>OPHY. 502 



motion, though it may be difturbed by certain caufcs, which Sir Ifaac 

 pientions, never can ceafe altogether. 



As to the origin of thefe tViTo motions ; the projedile motion, Sir 

 Ifaac fays, was impreffed upon the body at fome particular time, when 

 this our fyftem had a beginning. As to gravitation ; Sir Ifaac, in his 

 Principia, does not pretend to affign the caufe of it, as he tells us in 

 the conclufion of that work ; he only fays, negatively, that he does not 

 affirm it to be effential to matter ; but, as to the manner of its opera- 

 ting, it is evident that he underftood it to operate by impulfes incef- 

 fantly repeated : And in this way he accounts for its force increafmg 

 as the diftaiice from the center decreafes. There is, therefore, accor- 

 ding to Sir Ifaac, this difference betwixt the projedile impulfe and gra- 

 vitation, that the one is but fingle, and needs not be repeated, the 

 motion produced by it being one motion originally impreffed upon 

 body, and which continues for ever ; whereas the motion of gravita- 

 tion is continually accelerated by inceffant pulfations. 



From this account of the Newtonian philofophy, which, I hope, 

 every reader will think -a fair and a candid one, it is evident that Sir 

 Ifaac has made a machine, as 1 have faid, of the heavens, having given 

 to the celeftial bodies a motion that is mechanical ; for 1 call nucha' 

 KiVfl/ every motion that goes on of itfelf, without the immediate and 

 dired application of the moving power, which, according to my phi- 

 lofophy, is Mind, operating either immediately, or by the interven- 

 tion of other bodies. When it operates in the laiter way, and when 

 the motion is communicated from body to body, that motion is com- 

 monly called mechanical ; but, when the body, once put in motion, 

 continues to be moved of itfelf, without the immediate 0| eraiion of 

 Mind, though it do not communicate its motion, I call th:it mt^tion 

 likewife mechnnicah to diftinguifh it from motion produced immedi- 

 ately by Mind *. 



Of 



* See what I have faid of the difTerence betwixt a machine and the moving Power,- 

 page 190- 



The 



