Chap. 3. 'viTM'ifc < BO DIES. 29 



oweth, that they are more eafily divided in great, and likc- 

 wife, that they nrc by the force of naturall Agents divifible into 

 lefler parts : for both thcfc ( that is, facility of being divided, 

 andeafie divisibility into lefler parts ) are contained in being 

 more divifible; or in more enjoying the effeil ofquantity^which 

 is divifibility. From this again followeth, that in rare bodies 

 there is Icfle refiftance to the motion of another body through 

 it, then in denfe ones ; and therefore a like force paffeth more 

 calily through the one , then through the other. Again ; 

 rare bodies are more penetrative and active then denfe ones; be- 

 caufe being ( by their overproportion of quantity ) eafily divi- 

 fible into limll parts, they can fun into every little pore, and fo 

 incorporate themfelves better into other bodies then more denfe 

 ones can. Light bodies likewife muft be rarer., becaufe moft di- 

 vifible, if other circumftances concurre equally. 



Thus you fee decyphered unto your hand, the firfr divilion 

 of bodies flowing from Quantity as it is ordained to fubftance 

 for the competition of a bodie : for fince the definition of a bo- 

 dy is, A thing which hath parts^ and quantity is that, by which 

 it hath parts ; and the firfl propriety of quantity is, to be big- 

 ger or ft/f', and confequently the firft differences of having 

 parts, are to have bigger or lefle, more or fewer; what divifion 

 of a body can be more fimple, more plain, or more immediate, 

 then to divide it by its Quantity as making it have bigger or 

 Icfle, more or fewer parts in proportion to its fubftance? 



Neither can I juftly be blamed for touching thus on Meta- 

 phyficks,to explicate the nature of thefc two kinds of bodies; for 

 Metaphyficks being the iciencc above Phyficks, it belon^eth 

 unto her to declare the principles of Phyficks : of which, thele 

 we have now in hand, are the very firft f}ep. But much more, 

 if weconfider that the competition of quantity with fubftance, 

 is purely Metaphyficall ; we mufrneccrTarily allow the inquiry 

 into the nature of Rarity and Denfity. to be wholly Mctaphy- 

 ficall; feeing that the efTcnce of Rarity and Denfiry ftandeth in 

 the proportion of quantity to fubftance; if we believe Ariffotlc, 

 C the greateft matter that ever was, erf finding oi;t definitions 

 and notions ^and trufl to the iincontroulable reaibns we have 

 brought in the precedent diicourfe. 



This explication of Rarity and Denfity, by the composition. 5?. 



of 



