PIERRE EUGfeNE MARCELLIN BERTHELOT 113 



Science et Philosopliie and Science et Morale he treats of 

 the relation of science to human thought. The same 

 critical spirit manifests itself in his Histoire des Sciences : 

 La Chimie au moyen age, in which Syrian and Arabian 

 Alchemy is treated of. 



A partisan of Lavoisier, La Revolution chimique de 

 Lavoisier presents that point of view strongly. He also 

 published in 1898 his correspondence with Renan. 



The lectures which he delivered at the College de 

 France were published under the titles Lecons sur les 

 Methodes generates de Synthese en Chimie organique ; 

 Lemons sur la thermochimie ; Lecons sur les principes 

 sucres ; and Lecons sur I'isomerie. The application of 

 thermal chemistry to problems of life was treated of in 

 his Chaleur animate, and in 1901 he published three 

 volumes on Les Carbures d'Hydrogene. 



One point remains to be mentioned. It has sometimes 

 been objected that Berthelot kept science on a wrong 

 path by persistently retaining the old system of represent- 

 ing formulae, after all the rest of the world had aban- 

 doned it. The writer remembers well a conversation in 

 the late '80's, in which Berthelot defended his views. He 

 thought the position of those who employed the customary 

 notation (and, of course, they comprised practically the 

 whole chemical world) not unlike that of the defenders of 

 the phlogiston theory ! The retort was obvious, but not 

 made. Berthelot had not even the excuse of Cavendish, 

 who, after a calm, deliberate statement of the results of 

 his research in terms of the then new hypothesis of 

 Lavoisier, restated it in terms of the phlogistic method, 

 saying that he preferred to make use of the older and 

 better known language, rather than of the newer modes 

 of expression. For in 1890 Berthelot was, perhaps, the 

 only survivor of the older chemists. Professor Guye, who 

 attended his lectures in 1890-91, tells that the session was 



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