Mr. G. F. Rodvvell on the Theory of Phlogiston. 31 



The phlogistic theory is always associated with the name of 

 Stahl; but it may be well for us to inquire with what reason. 

 The principle itself had been recognized from the earliest ages ; 

 its functions had been developed physically by Descartes, and to 

 some extent chemically by Becher; the name was borrowed 

 from Becher. Stahl converted Becher's term into a substan- 

 tive, and conferred it upon Descartes's first element ; he also 

 extended the attributes of the principle, applied it diffusively, 

 and brought the full force of his comprehensive and methodical 

 mind to bear upon the subject. In the present day we give too 

 much credit to Stahl, or at least too little to Becher. It was 

 not the wish of Stahl that the theory should be attributed to 

 him alone ; for he actually developed it in the form of notes to 

 portions of Becher's Fhysica Subterranea, a treatise which he 

 designates " opus sine pain." Stahl did not consider that Becher's 

 genius was sufficiently recognized by the world*, and he never 

 wearies of praising him. At the end of a laudatory chapter in 

 the Specimen Becherianum he exclaims in his turgid and some- 

 what crass phraseology, u Audite hoc, manes Becheriani. DixiP 



Of the influence of the theory of phlogiston I need say but 

 little. It was not the first chemical theory ; it did not give the 

 first explanation of combustion ; and it was established in the face 

 of facts which carried with them its refutation. When the first 

 stage of its development was passed facts were adapted to the 

 theory, and phenomena were tortured and garbled so as to fit 

 in with it, by which means the progress of chemical science was 

 somewhat retarded. Even when Lavoisier had conclusively 

 proved the fallacy of the theory, this blind adherence shut the 

 eyes of the phlogistians to the merits of the new system, and to 

 the utter falsity of their own. Nevertheless the theory exer- 

 cised influence for good ; for by its means a certain amount of 

 order was introduced among a vast chaotic mass of chemical facts, 

 and phenomena were classed together and reasoned upon toge- 

 ther, and together submitted to similar processes of mental ana- 

 lysis after the manner so strongly advocated by Francis Bacon. 



When Mdme. Lavoisier, habited as a Greek priestess, burnt 

 the writings of Stahl upon an altar dedicated to the new science, 

 the downfall of the theory of phlogiston was not alone typified ; 

 for in that holocaust perished the vast system of empiricism 

 which had pervaded chemistry from the time of its origin until 



* Juncker, in the Conspectus Chemice, speaks of Becher in the follow- 

 ing terms: — ". Vir magno ingenio atque judicio, inque orani ferme scien- 

 tiarura genere versatus, imprimis etiam chemise studio addictus, quo feli- 

 cissime usus est ad illustrandam physicam, et vera rerum principia ac 

 mixtionem corporum investiganda atque edocenda." 



