140 HISTORY OF CHEMISTRY. 



an historical and a systematic view of his opinions 

 on the nature of salts and of his Phlogiston. 



Reception and Application of the Theory. The 

 theory that the formation of sulphuric acid, and the 

 restoration of metals from their calces, are analo- 

 gous processes, and consist in the addition of phlo^ 

 giston, was soon widely received ; and the Phlogistic 

 School was thus established. From Berlin, its ori- 

 ginal seat, it was diffused into all parts of Europe. 

 The general reception of the theory may be traced, 

 not only in the use of the term " phlogiston," and of 

 the explanations which it implies ; but in the adop- 

 tion of a nomenclature founded on those explana- 

 tions, which, though not very extensive, is sufficient 

 evidence of the prevalence of the theory. Thus 

 when Priestley, in 1774, discovered oxygen, and 

 when Scheele, a little later, discovered chlorine, 

 these gases were termed dephlogisticated air, and 

 dephlogisticated marine acid; while azotic acid gas, 

 having no disposition to combustion, was supposed 

 to be saturated with phlogiston, and was called 

 phlogisticated air. 



This phraseology kept its ground, till it was 

 expelled by the antiphlogistic, or oxygen theory. 

 For instance, Cavendish's papers on the chemistry 

 of the airs are expressed in terms of it, although 

 his researches led him to the confines of the new 

 theory. We must now give an account of such 

 researches, and of the consequent revolution in the 

 science. 



