42 HISTORY OF CHEMISTRY. [LECTURE III. 



ance of Berthollet's Statique Chimique. The second, on the 

 other hand, meets with vigorous contradiction ; Proust, a 

 fellow-countryman of Berthollet's, especially opposing the views 

 there stated. Thus there arises that renowned controversy 

 between these savants which is remarkable not only for the 

 talent which the opponents exhibit, but also for the extreme 

 politeness which is observed on both sides. 



Berthollet was at that time held in high esteem by the 

 scientific world. The sagacity which he had manifested in a 

 high degree in the working out of his book was justly admired. 

 It will be understood, then, that it was no small undertaking to 

 attack views which he had stated with much confidence, and' 

 had endeavoured to prove by experiments. At the same time 

 I may state here that the experimental part, especially, of the 

 Statique Chimique leaves much to be desired. When Berthollet 

 asserts that in the oxidation of the metals oxygen compounds 

 are formed with widely varying proportions, the reason of this 

 is that he analysed the crude product directly, and did not 

 first try to satisfy himself that he was not dealing (as was 

 generally the case) with a mixture. If, in addition to this, the 

 backward condition in which quantitative analysis stood at that 

 time is taken into consideration, it will then be understood how 

 Berthollet arrived at these erroneous results. 



Proust, on the contrary, proceeded very cautiously. He 

 endeavoured to find proofs of the purity of his substances, and 

 bestowed the greatest care upon the determination of the con- 

 stituents. He thus succeeded in discovering the hydroxides, 

 which had hitherto been entirely overlooked. 28 and were re- 

 garded as oxides containing a special proportion of oxygen. 

 We are indebted to Proust for investigations of the most of 

 the metals, which he usually published under the title Faits 

 pour servir a I'histoire, etc. 29 Further, he wrote detailed 

 treatises upon the sulphur and oxygen compounds, 30 in which 



28 Ann. Chim. 32, 41 ; Journ. de Phys. 59, 347. 24) Journ. de Phys. 

 51, 173 5 52, 409 ; 55, 325 <157 ; Ann. Chim. 32, 26 ; 38, 146 ; 60, 260, 

 etc. 30 Journ. de Phys. 59, 321 ; Sulphur compounds, ibid, 53, 89 ; 54, 



89 ; 59' 26 5- 



