On Catdrw, ami the Hm 'evolved during Coinlustion . l6l 



tion of caloric by combustion. According to rny conccrptiotl 

 of the experiments of Mr. Davy, they show that combusti"- 

 hies on decombusiion jabsofb the electric fluid : and as we 

 know that no quantity of electric fluid is given out on com- 

 bustion, it appears probable that this will lead us to the dis- 

 covery of this relation between oxygen and combustion. We 

 cannot for a moment consider the electric fluid and caloric 

 as synonymous : we must therefore draw this Conclusion ; 

 That the electric fluid is probably instrumental in producing 

 the caloric of combustion, and that as it disappears therein, 

 it must disappear to form something else. The combustible 

 unites with oxygen, and we tind that a large quantity of ca* 

 loric appears as a large quantity of electric fluid disappears ; it 

 is therefore extremely probable that the electric fluid which 

 disappears, forms the caloric which is generated. This is the 

 result I infer from it ; and the manner in which I conceive 

 it is effected, I shall now lay down : viz. that there are two 

 electrical fluids in nature ; and that the peculiar relation ox^ 

 ygen has to combustion consists in this — that oxygen is the 

 only substance with which one of them combines, and that 

 the other unites with the atoms of combustibles only ; — that 

 caloric is generated during combustion by the union of these 

 two fluids; consequently, that caloric is not a simple sub- 

 stance, but that its particles are composed of the two fluids 

 of electricity — this brings combustion to be a double de- 

 composition and combination, one of the products of which 

 is caloric ; that the electric fluids in some form or other are 

 blended with the atoms of matter, and like the atoms of 

 alkali and acids in salts veiling each other's properties; 

 that on the combination of oxygen with the atoms of the 

 combustible body, the electric fluids severally combined with 

 each, unite^ and form caloric, which is disengaged as gas 

 is set at liberty in other decompositions. As gas lighter than 

 atmospheric air is forced to rise up when at hbertv to do so, 

 so caloric, when disengaged, is by some power dispersed on 

 all sides. 



It appears probable from a varrety of circurpstances, that it 

 is the vitreous fluid of electricity that unites with oxygen, 

 and the resinous with combustibles. If we note, therefore, 



Vol, 30. No. 1 1^8. March 180^. L that 



