V fwtijl of B O D I E S* Cliap. i o. 



; fince there no refinance in the body it felf, and the aire 

 is continually cut m pieces, by the funne beams, and by che mo- 

 tions of little bodiesjtothat the adhefion unto aire of the body to 

 be moved* will be no hindetrance to this motion: eipeciallyjcon- 

 fjdcting the perpctuall new percuflions, and the multitude of 

 ehe<n* and how no force is fo little, but that with time and mul- 

 tiplication it will overcome any refinance. 



But if any man defireth to look upon, as it were at one view; 

 part- thewhole chain of this doftrine of gravity : let him turn the 

 Hcatt- firft caft of his eyes upon what we have faid of fire when wecx- 

 ?,^*doarioe plfcattd the nature of it. To wic, that it beginnqch from a little 

 touching gravi- fource ; and by extreme multiplication, and rarefaction, it ex- 

 tendcth it felf into a great fphere. And then he will perceive the 

 rcalon why light is darted from the body of the funne with that 

 iflci-edibie celerity, wherewith its. beams fly to vifitc the remo- 

 teft parts of the world ; and how of neceffity, it givcth- motion 

 to- all circumftant bodies ; fince it is violently thrutt forward by 

 {fe extreme a- rarefaction ; and the further it gocth, is ftill the 

 more ratified and dilated. 



Next, let him refleA how infinitely the quickneffe of lights 

 motion* doth prevent the motion of a moift body, fuch an one 

 as aire is: and then he will plainly fee, that the fir ft motion 

 v^hich- light is able to give unco the aii c, mutt needs be a fwel- 

 ling of that moift element, perpendicularly round about the 

 earth; for, the ray dependent, arKhhcray rcfleSenc.flying with 

 fb sreat ft ^)tcd, ti^at the- aire betweenchem cannot take a fbiv 

 mall ply any way before the beams of light be on both fides of 

 k:it followeth,that according to the nature of humide things, it 

 muftfirft onely fweli : for that is die beginning of motion in 

 them, when heat entered! into them, and worketh upon them. 

 And thus he may confidently reiolre him/elf, that the firft moti- 

 on which light canfeth in the aire, will be a fwelling of it be- 

 tween the two rayes towards the middle of them. That is; per- 

 pendicularly from thefurface of the earth. 



And out of this, he will likcwifc plainly fee, that if there be 

 any other Hcde dcnfc bodies floating in the aire, they muft- hke- 

 wiie mount a little, through this fwelling and riling of the aire.^ 

 But that mounting will be no more then the immediate parts of 

 the aire themfehes do move. Bccaufc this motion is not by way 



of 



