L S. Chap. 16". 



fo'.r.e bodies on fire, ami yet onely enlighteneth thcglafle and 

 the airc that are in the way. The realon of which is manifeft 

 to be the divers difpofitions of the different fubjeAs in regard 

 of the Agent : and therefore it is no wonder that divers cfte&s 

 (hould be produced according to chofe divers dilpofitions. 

 4. \ third pofition among Philofophcrs is ; that all bodies which 



ofrcactionand vvork upon others, do like wife as the fame time, wherein they 

 '"ron^'ac work; fuflFer from thofc they work uponrand contrariwifethat 

 ^."l ail bodies which fuflfer from others, do at the fame time work 

 back agam upon them. For the better understanding whereof, 

 Jet us confider thnt all action among .bodies is either purely lo- 

 call motion, or clfe locall motion with certain particularities 

 which give ic a particular name. As when we expreflfe the lo- 

 call motion of little atomes of fire, or of earth.- or water upon i 

 and into other bodies by the words of heating or cooling ; and 

 fo of the likjc.Now if the action be pure locall morion.and con- 

 fequently rhe crTer produced by that adion be merely change of 

 place ; we mutt call to mind how two dcnfe bodies moving one 

 sgaintt the other, do each of them bear before them fomelittle 

 quantity ofa rarer body immediately joyned unto them : and 

 confcquently,thele more rare bodies mutt be the firft to feel the 

 power of the dcnfe bodies and to receive impreflions from their 

 motions ; each of them, by the oppofite rare body, which like 

 an huifTicr gocth before to make way for his following matter 

 that obligeth him to this fervice. 



Now when thele rare nfliers have ttruggled a while like the 

 firft lightly-armed ranks of two armies in the interjacent field 

 between their main batnlies,that follow them clofc at the heels, 

 they muft at the length yield, when they are overborn by a 

 greater weight then they can Hiftain;and then they rccoile back, 

 as it were to fave themfelves by getting in among the files of 

 denfc bodies that drove them on ; which not opening to admit 

 them,& yet they ftill flying violently from the mattering force 

 that pnrfueth thena ; they prcfTe To hard upon what at the firft 

 preffcd them on, as notwithstanding their denfity and ftrength 

 they force them to retire back : for unlelfe they do fo, they are 

 not of the number of thofe that work upon one another. 



And this retiring.is cithrr on both fides, or but of one fide.lf 

 both; then ic is evident how each of them is an A gent, and each 



of 



