228 Professor Necker on Miner alog^y considered 



zoology or in botany ; for so predominating was the idea that 

 abstract substances were the real subjects of the classification, 

 that all the upper divisions were entirely chemical, but this dis- 

 tinction applied merely to the very subordinate notion of what 

 was to be considered as characterizing the species in general. 



Now, it is well known, that, in a classification founded 

 upon the natural method, although it is certainly essential to 

 have the notion of the species well defined, it is nevertheless 

 true that the specific characters are among the less important ; 

 the most valuable being the characters by which the higher di- 

 visions are designated. How could, then, a justly celebrated 

 French mineralogist assert, when speaking of common rock-salt, 

 that the circumstance of its being composed of muriatic acid and 

 soda, was a far more important character than its being soluble 

 in water ? Such a notion can be attributed only to these two 

 circumstances, — namely, that with this mineralogist, as indeed 

 with all mineralogists up to the present time, the abstract idea 

 of the substance was in a manner every thing, while the other 

 properties were considered so entirely subordinate to this idea, 

 that the mere notion and designation of the substance seemed to 

 him all that was required. Secondly, that he meant only to 

 characterize rock-salt as a species ; and, in fact, the notion of its 

 being a muriate, was but a chemical character to distinguish, as 

 a species, this substance from all the others of the chemical 

 genus soda; and the character of having soda for its base, was 

 nothing more than a specific character to distinguish the sub- 

 stance of rock-salt from all the other muriates. 



In the eyes of a naturalist, on the contrary, solubility in wa- 

 ter, connected as it is with many other characters, such as the 

 action on the sense of taste, the frangibility, the low degree of 

 hardness and of lustre, &c., is the connecting link of a whole 

 order of beings, and hence must stand high in the scale of im- 

 portance. 



§ 33. We shall not stop here to prove, that the importance 

 attached to a class of properties for its being the first to furnish 

 the means of distinguishing minerals hitherto confounded, or 

 of uniting others w^hich had been erroneously separated, is too 

 puerile to be here discussed. The fact that crystallography 

 was the first to unite hornblende, tremolite, and actinolite, for- 



