REMARKS ON COMBUSTION. Q$ 



tion does not take place when oxigen combines with produces gredients of fire 



or with the bate of fupporters. Thefe bodies contain no light. be abfent - 



The caloric of the oxigen of courfe is not feparated, and no fire 



appears. And this oxigen ftill retaining its caloric, is capable 



of producing combuftion whenever a body is prefented which 



contains light, and whofe bafe has an affinity for oxigen. 



Hence alfo the reafon why a combuftible alone can reftore 



combuftibility to the bafe of a product. In all fuch cafes a 



double decompofition takes place. The oxigen of the product 



combines with the bafe of the combuftible, while the light of 



the combuftible combines with the bafe of the product. Thus 



when iron acls on water, the oxigen of the water combines 



with the bafe of the iron, while at the fame time the light of the 



iron combines with the hidrogen of the water, and occafions 



its efcape in the ftate of gas. 



But the application of this theory to all the different pheno- 

 mena defcribed above, is fo obvious, that it is needlefs to give 

 any more examples. Let us rather inquire into the evidences 

 which can be brought forward in its fupport. 



10. Now as caloric and light are always emitted during They muft 

 combuftion, it follows that they muft have been previoufly therefore have 

 component parts either of the combuftible, or of the fupporter, JJ ,n °he com- 



Or of both. buftible,thefup- 



That the oxigen of the fupporters contains either one or both P orter » or bot * 

 of thefe fubftances, follows incontrovertibly from a fad already 

 mentioned, namely, that the oxigen of produces will not fupport 

 combuftion, while that of fupporters will. Hence the oxigen of 

 fupporters muft contain fomething which the oxigen of produces 

 wants, and this fomething muft be caloric, or light, or both. 



That the oxigen of fome of the fupporters at leaft contains References to 

 caloric as an ingredient, has been proved, I think, in a fatisfac- fa & s : Caloric* 

 tory manner, by the experiments of Crawford, Lavoifier, and 

 La Place. Thus the temperature of hot blooded animals is 

 maintained by the decompofition of air. Now if the oxigen 

 of one fupporter contain caloric, the fame ingredient muft ex- 

 ift in the oxigen of every fupporter, becaufe all of them are 

 obvioufly in the fame ftate. Hence I conclude that the oxigen 

 of every fupporter contains caloric as an effential ingredient. 



The light emitted during combuftion muft either proceed Light, 

 from the combuftible or the fupporter. Now that it proceeds 

 from the combuftible muft appear pretty obvious, if we recoi- 

 led 



