as a Branch of Natural History^ Sfc, 219 



he has done in the manner of his predecessors. The objects of 

 his study have not been, it is true, abstract ideas of substance, 

 for he has carefully avoided all that related to chemical compo- 

 sition, but abstract ideas of certain physical matters, possessing 

 certain physical properties, but no character whatever of indi- 

 viduality *. Had Mohs thought of comparing together his in- 

 dividuals, and had he got a more thorough and extensive know- 

 ledge of the nature and purpose of natural history, he never 

 would have entirely laid aside characters so important as those 

 derived from chemistry, he never would have assembled toge- 

 ther in the same orders minerals entirely different in chemical 

 composition, and he would then have really and effectually re- 

 stored to natural history the knowledge of mineral bodies. 



§ 15. It is, therefore, only by the consideration of individuals 

 that the questions, constantly discussed among mineralogists as 

 to the superiority to be assigned to the chemical composition or 

 to the physical properties of minerals, can be set at rest. When 

 the nature of the body under consideration is not perfectly de- 

 fined, and when the reasoning is carried on in too general a way, 

 as has always been the case, each mineralogist is apt to over- 

 rate the value of properties which his taste or circumstances 

 have made him most familiar with, and it is difficult to pro- 

 nounce in so arbitrary a matter. But when an individual is 

 given which is well defined in form, in properties, and in che- 

 mical composition, it becomes evident that all these attributes, 

 the form, the properties, and the composition, are equally in- 

 herent in the nature and essential to the existence of such an 

 individual, and so they stand on an equal footing one with the 

 other. It is one of the great advantages of the consideration of 

 individual bodies, that these individuals are the most real and 

 natural syntheses of properties or characters, in regard to which 

 every other attempt to synthesis would be arbitrary and fantas- 

 tical. 



§ 16. Let us now follow in regard to our mineral individuals 



• As is evident, by his having admitted into his method aeriform and liquid 

 matter, where no trace of individuality is to be found, and as may be likewise 

 demonstrated, in examining the part which crystallization acts in his manner 

 of considering solid minerals. 



I 



