icy A TrCAiife of BODIES. Chap, io. 



and are parted from their volatile companions of fire or lighc, 

 inuft begin to come down apace., when other new atomes 

 ( winch ftill have their light incorporated with them) doafcend 

 to where they are, and do go beyond them by reafou of their 

 greater levity. And as the latter atomes come up with a violence 

 and a great celerity, fo muft the firft go down with a finarc 

 impulie : and by confequence, being more denfe then the airein 

 which they arecarryed, mi: ft of necffliry cut their way through 

 that liquid and rare medium and go the next way to fupply the 

 defect and room of the atomes which afcend; ("that is, perpen- 

 dicularly to the earth ) and give the like motion to any body 

 they find in their way, if it be fulceptible of fjch a motion: 

 whichit is evident that all bodies are ; unlcfle they be ftruckcn by 

 fomc contrary impulfe. For fince trine a bodies being in a place, 

 is nothing elfe but the continuity of its outfide to theinfidc of 

 the body that containeth it and is its place, it can have no other 

 repugnance to locall motion (w hich is nothing elfe but a x fuccefl 

 five changing of place ) befides this continuity. Now the na- 

 ture of denfity, being the power of dividing ; and every leaft 

 power having fome force and efficacy, ( as \ve have fhewed 

 above) it followeth that the ftroke of every atome ( either de- 

 fcending, or afccnding) will work fomething upon any body 

 (though never fe bigjit chanceth to mcoumer with, -and ftrike 

 upon in its way, unleffe there be as ftrong an impulfe the con- 

 trary way, to oppofe it. But it being determined, that the de- 

 fcending atomes aredenfer then thole that afcend; it followeth 

 that the dcfcending ones will prevail. And confequently,alldenlc 

 bodies muft neceflarily tend downwardsto the center (which is, 

 to be//rrfz/7)if Ibme other more denfe body do not hinder them. 

 .. Out of this difcourfe, \ve may conclude that there is no fucli 



G-avity and le- thing among bodies^as pofitive gravity or levity: but that their 

 mfie'an'StriJ."" coHrlc upwards or down wards happencth unto them by the or- 

 iccaii incimati- ^ cr o f nature, which by outward caufesgireth them an impulie 

 mikiathe one of thefe wayes : without which, they would reft quietly 

 bodies ihem- wherefocver they arc, as being of themfelvcs indifferent to any 



{elves which . J r . r . . . J 



atotcnTcH motion. But becauie our words exprelle our notions, and they 



L*hl yand flfe ^ ra " 1 d according-to what appeareth unto us; when we ob- 



ferveany body to defcend conftantly towards our earth, we 



call it heavy j and if it move eomrarywilc, we call it light. 



But 



