30 Prof. Nauinann on Mineralogical Classification. 



neralogists, because, by undervaluing the peculiarities im- 

 pressed on the whole physiognomy of the physical individual, 

 they have, from the mere presence of this or that ingredient, 

 united minerals in groups, which cannot by any possibility 

 be satisfactoi'y in a physiographical point of view. 



A middle course must therefore be sought for, which, by 

 avoiding, on the one hand, self-sufficient oryctognostical, and, 

 on the other, exclusive chemical one-sidedness, may escape 

 the reefs on which all those mineral systems have been 

 wrecked, that have been founded either entirely on exter- 

 nal physiognomy, or entirely on the presence of certain com- 

 ponent parts. Among chemists, Leopold Gmelin was the 

 first in Germany who attempted this middle path ; and it is 

 generally acknowledged that his mineralogical system has 

 been much more successful than the previous purely chemi- 

 cal attempts of the same kind. In 1828, 1 published an ele- 

 mentary work on Mineralogy, in which I endeavoured to ad- 

 here as much as possible to the principles laid down and 

 followed by Gmelin. The arrangement, however, then at- 

 tempted of two hundred species could not make any claim 

 to the term mineralogical system. At a later period Glocker 

 published his Elements of Mineralogy, in which are contained 

 very many and extremely successful combinations, founded 

 on similar principles ; and these, together with the classifica- 

 tions of Weiss and Breithaupt, previously partially made 

 known, proved that the principle of the mixed system is 

 capable of yielding very satisfactory groups. More recently, 

 Whewell, in his History of the Inductive Sciences, has criti- 

 cally examined the fundamental principles of the mineralo- 

 gical systems previously published, and has triumphantly 

 pi'oved, that a 7nixed si/ stem alone can satisfy the require- 

 ments of physiography. 



Impressed with the correctness of this view, and en- 

 couraged by the favourable opinion expressed by Whewell 

 in regard to my first effort, I now venture to present to the 

 public a mineralogical aiTangement, which, although founded 

 essentially on the same principles as my first atteiTipt, must 

 yet lead to somewhat different results. 



Every attempt at a mineralogical classification ought to 



