40 A Tn.itife ^/BODIES, Chap, j. 



CHAP. V. 



Of the oyerAtioHf f tht Elements in gcnerall. tx/W of 

 their aft ivi ties compared with one another. 



T . T TAving by our former difcourfe inquired out what degrees, 

 ope- JL land proportions of rarity and denfity compounded with 

 gravity,are necctfary for the produ&ion of the Elemencs,& firft 

 Tifion.oucof qualities ; whofe combinations, frame the Elements : our next 



wlvch rcfultcth * r i t Ji rC L ,-i 



iccali motion, confideranon in that orderly progreflc we nave propofed unto 

 our (elves in this treatife (wherein our aim is, to follo\v fuc- 

 celfively the fteps, which nature hath printed out unto us ) will 

 be to examine the operations of the Elements, by which they 

 work upon one another. To which end, let us propofc to our 

 felves a rare and a denfe body encountring one another by 

 the impulfe of lomc exterior agent. In this cafe, it is evident, 

 that fincc rarity implyeth a greater proportion of quantity , 

 and quantity is nothing but divifibility, rare bodies muft needs 

 be more divisible then denfe ones : and consequently, when 

 two fi.'ch bodies arc prefled one againft another ; the rare body 

 not being able to refift divifion {b ftrongly, as the denfc one is; 

 and being not permitted to retire back, by reaibn of the ex- 

 tern violence impelling it againft the denfe body; it followeth, 

 that the parts of the rare body muft be fevered, to let the denfe 

 one come between them : and fb the rare body becometh di- 

 ridcd, and the denlc body the divider. And by this we fee that 

 the notions of divider and divifible do immediately follow 

 rare and denfe bodies; and dofo much the more properly agree 

 unto them,as they exceed in the qualities of Rarity arid"benfity. 

 Likcwiie, we are to obferve in our cafe, that the denfe or di- 

 viding body muft neccflarily cut and enter further and further 

 into the rare or divided body; and fo the fides of it be joyned 

 fucceffively to new and new parts of the rare body thatgiveth 

 way unto it, and forfake others it parteth from. Now the rare 

 body being in a determinate fituation of the univerfc, ( which 

 we call being in a place, and is a neceflary condition belonging 

 to all particular bodies) and the denfc body coming to be 

 within the rare body, whereas formerly it was not fb : it fol- 

 loweth , thit it lofcth the place it had, and gaineth another. 

 This efreft, is that which we call locall motion. 



And 



