HYDROGEN EXTINGUISHES COMBUSTION. 97 



burn in close vessels from which bodies denominated (in our 

 chemical system) supporters are totally excluded : the latter, 

 are the atmospheric air, oxygen, chlorine, iodine, and fluorine ; 

 but one of which, by our theory, is considered simple, or 

 elementary namely, oxygen . 



Now, a common candle, the oils, resins, wax, alcohol, &c. 

 which are known to be compounds of oxygen, hydrogen, and 

 carbon, do not burn in close vessels, unless some one of the 

 supporters are present, 



It will also be found that some bodies require one supporter, 

 and some another (according to their constituents) ; and the 

 only general one, is the atmosphere. 



Hydrogen gas will not burn unless in contact with atmo- 

 spheric air, or its principles. 



If inflammable bodies, in the state of ignition, are introduced 

 into hydrogen gas, they are immediately extinguished. 



Pure carbon is not altered, or consumed, by the strongest 

 heat that can be applied to it, the atmosphere and its consti- 

 tuents being excluded. 



Charcoal, although it is a compound, and known to contain 

 hydrogen, as ascertained by Davy, and oxygen, as imputed by 

 Fourcroy ; and quere, from its color, a portion of azote, as I 

 presume to assert yet will not burn, if the atmosphere, or 

 oxygen, are not present. 



Bodies composed of carbon and hydrogen, with or with- 

 out other matter in combination, are the most subject to com- 

 bustion in the atmosphere. Thus, we have in coal a familiar 

 example of a body termed inflammable, composed of carbon 

 and hydrogen, as two acknowledged constituents, combined 

 with other matter, when ignited in the atmosphere, which is 

 known to be constituted of oxygen and nitrogen, burns, pro- 

 duces light and heat ; while the absence of the oxygen would 

 totally prevent the formation of light, and would completely 

 extinguish combustion. 



In the experiments made by Sir II. Davy on inflammable 



H 



