Professor Moll's General Reflections on Mineralogy . 19 
other properties of a science. And here, although the words 
6 natural history ,’ and 4 natural-historical properties,' have been 
frequently made use of, and will be used hereafter, it might still 
remain a problem to be solved, whether or not this science be 
Natural History. 
In reference to this matter, the first object with which we have 
to occupy ourselves, is to examine these properties by themselves , 
and not in conjunction, as several of them occur in minerals. 
This will enable us to obtain a correct idea of them, to judge of 
their merits, and to apply them usefully ; and for this purpose 
they must be disposed in a certain order, and designated by ap- 
propriate expressions. They are here explained as natural- 
historical, and not as physical, properties ; that is to say, they are 
exhibited only in so far as they are applicable to Natural History, 
their explanation as physical properties forming part of Natural 
Philosophy, This explanation, as being a general preparation 
to the farther development of the science, is also necessary in 
Zoology and Botany ; and it is called the Terminology , because 
it contains, besides the general investigation of those properties, 
also the explanation of the expressions, which are henceforth, 
for the sake of precision and perspicuity, to be used in a deter- 
minate and peculiar sense. A department of Geometry, analo- 
gous to terminology in Natural History, is that devoted to 
definitions; and here there are none of those difficulties with 
which we have to struggle in Natural History, because empirical 
ideas are totally excluded. Hence it is a particularly favourable 
circumstance in miner alogical terminology, that geometrical de- 
terminations may be received in it, the influence of which even 
extends beyond the limits of terminology, and confers so high a 
degree of evidence upon the idea of the species, one of the most 
important general ideas of the science, that in this particular it 
has evidently obtained a great advantage over Botany and Zoo- 
logy. It is a property of every simple mineral to assume a re- 
gular form, that of crystals , whenever it becomes solid, and no 
external impediments have existed during the progress of its 
formation. Crystallography , therefore, is that part of termino- 
logy, in which it is possible to introduce mathematical considera- 
tions in the investigation of the natural-historical properties of 
b 2 
