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CHAPTER VII. 



APPLICATION AND CORRECTION OF THE OXYGEN 

 THEORY. 



SINCE a chemical theory, as far as it is true, 

 must enable us to obtain a true view of the 

 intimate composition of all bodies whatever, it will 

 readily be supposed that the new chemistry led to 

 an immense number of analyses and researches of 

 various kinds. These it is not necessary to dwell 

 upon ; nor will I even mention the names of any of 

 the intelligent and diligent men who have laboured 

 in this field. Perhaps one of the most striking of 

 such analyses was Davy's decomposition of the 

 earths and alkalies into metallic bases and oxygen, 

 in 1807 and 1808 ; thus extending still further that 

 analogy between the earths and the calces of the 

 metals, which had had so large a share in the 

 formation of chemical theories. This discovery, 

 however, both in the means by which it was made, 

 and in the views to which it led, bears upon sub- 

 jects hereafter to be treated of. 



The Lavoisierian theory also, wide as was the 

 range of truth which it embraced, required some 

 limitation and correction. I do not now speak of 

 some erroneous opinions entertained by the author 

 of the theory ; as, for instance, that the heat pro- 

 duced in combustion, and even in respiration, arose 



