Anahjfis of the Air\ 273 



them : And therefore the Candle and Matches 

 ceafing to burn, foon after they are confined 

 in a fmall quantity of air, feems not to be 

 owing to their having rendred that air effete, 

 by having confumed its vivifying fpiritj but 

 fhould rather be owing to the great quantity 

 of acid fuliginous vapours, with which that 

 air is charged, which deftroy a good deal of 

 its elafticity, and very much clog and retard 

 the elaftick motion of the remainder. 



And the effeft the half exhaufting of a 

 receiver has upon the elafticity of the re- 

 maining half of the air, feems to be the rea- 

 fon why the flame of a Candle does not 

 continue burning, till it has filled the recei- 

 ver it (lands in with fumes, but goes out 

 the quicker, the fooner the air is drawn out 

 to that degree ; which feems therefore to be 

 owing to this, that an air tariffed to double 

 its fpace, will not expand fo briskly with 

 the warmth of flame, as a more condenfed 

 air will d«u And confequently a&ion and 

 re-a£tion being reciprocal, will not give fo 

 brisk a motion to the flame, which fubftfts 

 by a conftant fucceffion of frefli air, to top- 

 ply the place of the either abforbed, or much 

 dilated air 3 which is continually flying off, 



T ' And 



