ANALYTICAL SYSTEM. 143 



with nearly the same degroe of ease. The system of crystallization, 

 in most cases, is a problem to which the lowest attainments in miner- 

 alogy are adequate; or rather, it is one, which, until the pupil is able 

 to master, he is unprepared to take a single step to advantage in the 

 study of the mineral kingdom. The orders in the remaining class 

 need only to be mentioned, to be recognized. 



. 113. ARRANGEMENT OF THE SPECIES WITHIN THE 

 ORDERS. 



The species are arranged in each order, in a series, de- 

 pending upon the property of Hardness, except in the two 

 last orders of the third class, where it depends upon the 

 property of Specific Gravity. 



Where the series depends upon the property of hardness, the or- 

 ders commence with the softest species, and terminate with the 

 hardest: in the other case, it begins with the lightest and termin- 

 ates with the heaviest. 



Had it promised an additional convenience, in arriving at the 

 names of minerals, through the use of this system, it would have 

 been easy to have divided the orders into genera, depending upon 

 fixed degrees of hardness and specific gravity. The idea of a series 

 within the genus, however, founded upon these properties, seemed 

 preferable, inasmuch as it possesses every possible facility which 

 would attend the division in question, besides the advantage of ren- 

 dering the arrangement considerably less complicated, both as res- 

 pects the nomenclature and practice. 



