ANALYTICAL SYSTEM. 141 



erals constitute by far the largest part of those requiring determina- 

 tion, and they are wholly destitute of any tendency towards a higher 

 degree of perfection. As we find them, so they remain, (unless, 

 indeed, they become, as sometimes is the case, more imperfect still, 

 from external agencies;) and, unlike the determination of imper- 

 fect plants, by the aid of those which are more perfect, it is seldom 

 passible to determine them from their association with crystallized 

 individuals of the same species. From this we see, that a method 

 which should omit to provide for such minerals as aie not fully per- 

 fect in their characters, would be extremely imperfect in general 

 practice. 



As a consequence of this necessity of providing means for the de- 

 termination of imperfect minerals, lias arisen the-' frequent division 

 of the species. Thus, portions of the species Fluor are found in all 

 of the classes, according as the individuals are crystallized, cleav- 

 able or massive. It is to be remarked, however, that this division 

 within the species, (unknown in the other departments of natural 

 history,) never takes place in the crystallized individuals of the min- 

 eral kingdom ; among which only should we expect to find the rule 

 of preserving the species unbroken observed, since they alone cor- 

 respond to the classifiable objects in zoology and botany. 



. 110. DIVISION OF THE CRYSTALLIZED CLASS INTO 

 ORDERS. 



Crystallized minerals are divisible into orders, depending 

 upon their different systems of crystallization. 



Each system of crystallization affords the basis of an order, within 

 the present class. And the division takes place throughout, without 

 impairing, in a single instance, the unities of the species it contains; 

 a circumstance obviously depending upon the fact, that all the crys- 

 tals of any one species belong to one and the same system of crystal- 

 lization. No species will therefore be found to occur, in the crystal- 

 lized class, in more than one order. 



<. 111. DIVISION OF THE SEMI-CRYSTALLIZED CLASS 

 INTO ORDERS. 



Semi-crystallized minerals are divisible into orders, upon 

 the same principle with the crystallized minerals. (. 110.) 



