Analyjis of the Air. 283 



But by many of the preceding Experi- 

 ments, it is evident, that the matter loft 

 in the Analyfis of thefe bodies was clat 

 :ick air, a very a&ive principle in fire, 

 but not an elemental fire, as he fuppofes. 



"Mr. Geoffrey compounded fulphur of 

 " acid Salt, Bitumen, a little Earth and oil 

 cc of Tartar." Mem. de I' Acad. Anno 1703. 

 In which oil of Tartar there is much air by 

 Experiment 74, which air was doubtlefs by 

 its elafticity very inftrumental in the inflam- 

 mability of this artificial fulphur. 



If fire was a particular diftind: kind of body 

 inherent in fulphur, as Mr. Honiherg, Mr. 

 Letnerjy and fome others imagin, then fuch 

 fulphureous bodies, when ignited, fhould 

 rarify and dilate all the circumambient air ; 

 whereas it is found by many of the preced- 

 ing Experiments, that acid fulphureous fuel 

 constantly attrafts and condenfes a confide- 

 rable part of the circumambient elaftick air. 

 An argument, that there is no fire endued 

 with peculiar properties inherent in fulphur 5 

 and alfo that the heat of fire confifts prin- 

 cipally in the brisk vibrating action and re- 

 action, between the elaftick repelling air, 

 and the ftrongly attra&ing acid fulphur,which 



fulphur 



