V. ANTIENT METAPHYSICS. 399 



which the Mathematicians call a Parabola ; for, unlefs the Body 

 moved by the Impulfe was to go forward forever, without returning 

 to the Earth again, the order and regularity, which we obferve in Na- 

 ture, requires that it fhould defcribe a curve of a regular kind, whofe 

 properties can be inveftigated and demonftrated : And, according- 

 ly, fuch is that fedion of the Cone we call a Parabola. But if, in 

 defcribing this figure, it be flopped or interrupted, it is moft natu- 

 ral that it fhould refume its natural and ordinary Motion of De- 

 fcent ; or, if the Progreffive Motion be not quite flopped, but only 

 intercepted and the diredion of it altered by a horizontal plane, 

 that it fliould go on in the diredion of that plane, by virtue of the 

 Progreflive Motion which it receives from the impulfe. In like 

 manner, the Mind in the Iron or the Loadflone, which moves them 

 toward one another, if either be removed from the other, the fame 

 Mind will carry the Loadflone or Iron downward in its natural de- 

 fcent. 



And thus, I think, I liave proved, that even the Motion of a Pro- 

 jedile is not a compounded Votion : And, if fo, every Newtonian 

 will, I believe, allow, that neither is the Motion of the Planets 

 compounded, upon the fuppofitlon that this Motion is produced en- 

 tirely by Mind ; for, if it be produced by Body only, or both by 

 Mind and Body moving the Body in different diredions, it is evi- 

 dent that it mufl be mixed ; whereas, upon the hypothefis of ihofc 

 who are not demi-fpirltuallfls, to ufe an exprefTion of Dr Prieflley but 

 maintain that Mind is the only Moving Power in the Solar Syftcm, 

 it follows, of neceflary confequenee, that the Motion of the Pla- 

 nets is altogether by the agency of Mind, in the fame manner as the 

 Motion of Animals is here on Earth ; with this difference only, that 

 the Circular or Elliptical Motion is more peifedly perfoxmed by the 

 Planets, as having no organs or members of tlicir Body, and 



bein^ 



