SYSTEMATIC ARRANGEMENT OF MINERALS. 5 
however, is by no means the case. The same general 
appearance sometimes prevails in substances that are 
very different from each other ; and the same stone, 
in its different states, is often extremely varied in its 
appearance. To these difficulties it must be added, 
that the combinations of mineral substances are multi- 
plied to a great extent. A little application, however, 
particularly if the student be possessed of a collection 
of arranged and named specimens, which he will have 
no difficulty in procuring at a reasonable price, will 
enable him to overcome all the obstacles that otherwise 
might impede his progress in beginning to acquire a 
knowledge of this interesting science.* 
12. The most simple and natural division of minerals 
is into four classes, of, 1. STONES ; 2. SALTS ; 3. COM- 
BUSTIBLES ; and, 4. METALS ; and the following table, 
which has chiefly been arranged from the system of 
Werner, the well-known German mineralogist, will 
exhibit a tolerably correct outline of the classification 
of these substances. To reduce the whole within the 
compass of a single page, many of the families, how- 
ever, have necessarily been omitted. 
* Such collections are supplied by Mr. Mawe, No. 149, 
Strand, London. His terms, for collections containing from 100 
to 200 specimens, are 5 guineas; from 200 to 300 specimens, 
10 guineas; and from 300 to 400 specimens, 15 guineas. 
For collections containing from 350 to 400 specimens, more 
select, and comprising a better suite of precious stones, he 
charges from 20 to 30 guineas; and for larger collections, from 
50 to 100 guineas. At the particular request of the author, Mr. 
Mawe has arranged a few collections of minerals, and numbered 
them in such manner as to correspond with, and illustrate the 
present volume. 
