296 Professor Mohs’s General Reflections on 
a manner, as that it may become possible to discover in it the 
description of every individual contained in the species ; so that, 
in fact, it may be said to include the descriptions of every indi- 
vidual, both known and unknown, without being itself a descrip- 
tion, properly so called, at all. The study of the general de- 
scriptions is, therefore, to be recommended to all those who wish 
to acquire a more detailed knowledge of the productions of the 
mineral kingdom ; and we should bestow the greatest possible 
attention upon the construction and completion of them, in treat- 
ing the subject of scientific mineralogy. 
The general descriptions are independent of systems, and pre- 
suppose nothing but the correct idea of the species : we must 
know what a species is. They are not subservient to the recogni- 
tion or determination of individuals, because these require single 
characteristic marks, which must at the same time be well defined, 
if they are meant to be distinctive ; and of such the general de- 
scription does not contain any thing. This determination is the 
sole object of the characteristic. Hence we may infer what 
must be the consequence, if we give the characters such an ar- 
rangement, that they may at the same time represent the general 
descriptions of the species ; and the latter such an arrangement, 
that they may, in like manner, serve the purpose of characters, 
as is but too generally the custom in mineralogical works. Nei- 
ther of them will entirely answer their purpose ; and those w T ho 
wish to become acquainted with minerals, or to acquire some na- 
tural-historical knowledge of them, find themselves under the 
necessity of proceeding upon the old empirical plan, notwith- 
standing the number of works on mineralogy, which may in 
other respects contain the most valuable information. They 
must content themselves with a superficial and broken sort of 
knowledge, to which they themselves do not attach any security, 
for they have recourse to chemical analysis for confirmation ; 
whereas the methodical way of proceeding leads to information 
that is solid, connected, and as complete as possible, and which 
is not only in itself firm, but also forms the scale of measuring 
and judging of the results of other sciences, in so far as they re- 
fer to the same objects. 
The assemblage of all the general descriptions is termed the 
Physiography. From the explanations given above, it will 
