Chap." 3. 



the parts of water arc more fevered then the parts of lead,there 

 muft be fome other fubftancc to keep the parts of it afunder: let 

 us fuppofc this to be aire: and I ask, Whether an cquall partof 

 aire be as heavie as fo much water? or whether it be not ? If 

 yo^fay, it is; then the compound of water and aire muft be as 

 lieavieas lead.; fceiagthat their parts one with an other are as 

 much compacted as the parts of lead are. For there is no diffe- 

 rence whether thofe bodies, whole little parts are compared to- 

 gether, be of the lame fubftance.,or ofdivers, or whether the one 

 be divided into fmallcr parts then the other , or no> ( fo they be 

 ofequall weights ) in regard" of making the whole equally hea- 

 vie : as you may experience, if you mingle pin-duft with a 

 fand of equal! weight, though it be beaten into far re Irnaller di- 

 viiions then the pin-duft, and put them in a bag together. 



But if you fay, that aire is not fo heavy as water; it muft be, 

 becaufe every part of aire hath again its parts more fevered by 

 fome other body, then the parts of water are fevered by aire. 

 And then I make the fame inftance of that body which feveredi 

 the parts of aire. And fb at the laft ( fince there cannot a&ually 

 bean infinite procefle f bodies one lighter then another ) you 

 mutt come to one, whole little parts filling the pores and (paces 

 between the parts of the others, have no fpaces in thcmfelves to 

 be filled up. 



But aflbon as you acknowledge fuch a body to be lighter 

 and rarer then all the reft, you contradict and deftroy all you 

 faid before. For by reafon of its having no pores, it followeth 

 by your rule, that the little parts of it muft be as heavy , if not 

 heavier, then the little parts of the fame bignelTc of that bodie 

 whofe pores it filleth ; and confequencly it is proved by the ex- 

 perience we alledged of pin-duft mingled with fand, that the 

 little parts of it cannot by their mingling with the parts of the 

 body in which it is immediately contained, make that lighter 

 then it would be if thefe little parts were not mingled with it. 

 Nor would both their parts mingled with the body which im- 

 mediately containeth them, make that body lighter. And fo 

 proceeding on in the fame fort through all <the mingled bodies, 

 till you come to the laft, that is immediately mingled with wa- 

 ter; you will make water nothing thelighter,fb? being mingled 

 with all thefe; and by confequence It fhould be as heavie and 

 as denfc as lead. B 4 Now 



