and the Theory of Chemical Types : Nomenclature. 181 



dify the opinion on the function of the organic radicals, we 

 should cite in the first place the important observations of M. 

 Laurent on the essence of bitter almonds, and those not less 

 remarkable of M. Piria on the hydruret of salicyle *. To re- 

 sume ; nothing hinders me from retaining the name of organic 

 radicals for certain molecular groups capable of being substi- 

 tuted for elementary bodies which may reciprocally be sub- 

 stituted for them, but these groups may in their turn be mo- 

 dified by substitution, like the other bodies which do not per- 

 form this function. 



I had a memoir of M. Gehrardt put into my hands, but 

 too late for me to make use of it in the present notice, in which 

 these questions are examined in a manner which appeared to 

 me very worthy the attention of chemists. 



Nomenclature. — Amongst the questions which are presented 

 to us as being the immediate consequence of the point of view 

 which we have just set forth, there is one which deserves par- 

 ticular attention; it has relation to the principle itself of our 

 chemical nomenclature, and to the modifications which the 

 progress of the science has led us to make it undergo. 



At the memorable period when the French Academicians, 

 under the influence of the immortal discoveries of Lavoisier, 

 conceived and unfolded the project of a reform in the old che- 

 mical nomenclature, they grounded themselves upon the view 

 which Lavoisier himself had just established, that is, upon the 

 existence of those undecomposed substances which were recog- 

 nized as the material elements of all bodies. 



Seeing that by the aid of these elements all the bodies of 

 nature could be produced, that in associating them two and 

 two binary bodies were formed, that in combining these one 

 with another salts were produced, and that in combining these 

 salts in their turn double salts were obtained, the nomencla- 

 ture had to follow the philosophical principle in all its deve- 

 lopments. It required that the names of the elements should 

 be set forth in those of the binary compounds, that they should 

 reappear in the names of simple salts, in those of double 

 salts, &c. 



What strikes us in the chemistry of Lavoisier, and in the 

 nomenclature which was the consequence and the expression 

 of it, is the antagonism of the elements which combine to form 

 the binary compounds ; it is the antagonism of the acids and 

 of the bases which combine to form salts; it is the antagonism 

 of the salts which combine to form double salts, &c. 



* [See Lond. and Edinb. Phil. Mag., vol. xvi. p. 210, 211.] 



