PHYSICAL AND LITFRARY 97 



is fet on fire, makes the air fly off with 

 great impetuoliry. 



It is an eledive attradlion, as above 

 oblerved, that confines air within water. 

 Kfeat, by its power of expanfijn, Teparates 

 the particles of air and water ^t a greater 

 diftance from each other •; and this cir- 

 cumftance, without other change, converts, 

 the mutual attraction into a mutual, re- 

 pulfion, by which the air, a? the lighter, 

 body, fiies upward. 



We find not any mutual .attradllon be- 

 tween the particles of wat^r. .lOiithe- con-^. 

 trary, as water is expanded by heat, and 

 qondenfed by cold, it is €ertain that the 

 particles of water in its natural ftate ne- 

 ver come into contact ; a^nd to \?vhat other 

 caufe can this -be owing but to a: mutual 

 repulfion ? Such th^n is the condition of 

 water, that by mutual repu^fiqn the parti-. 

 cles arc kept diftant from e.^ch other ; and 

 tho' by a contrary agency^ overcoming in 

 part the mutual repulfion, the particles are 

 brought nearer to each other, yet hither- 

 to tl\ere has not been difcovered any power 

 fufilcient to force the particles into adual 

 Vol. in. N contraa. 



