een A ee 
Puates 32, 33, 34, 35, 36. 
Introduction. 
Mrwneratoey is that part of natural science which treats of the unmixed, 
morganic bodies occurring in nature, whether these be simple or compound. 
It may, under a certain point of view, be considered as a department or 
offshoot of chemistry, but is nevertheless as much entitled to a separate 
place among the sciences as geology or botany. It must indeed be treated 
of independently, since by determining the differences of individual minerals, 
and by ascertaining certain common characters, it brings the variety of 
inorganic nature into a position for proper appreciation ; just as is done for 
the organic world by its two sisters, botany and geology. As occupied with 
imorganic matter, it stands in closest approximation to geology, this treating 
of the combination of mineral matter into rocks, and the distribution, 
stratification, degradation, or decomposition of these rocks, in various ways 
and in different parts of the globe. Mineralogy deals only with individual 
specimens from these various rocks, which it classifies according to certain 
systems, describes them according to their external and internal characters, 
and adds to this the assistance furnished by chemistry, in determining their 
atomic constitution. 
The expression, “unmixed, simple, or compound inorganic bodies,” requires 
some further explanation. The surface of the earth rarely affords the 
matter of its solids, its water, and its atmosphere, in an elementary, and 
consequently inseparable form. Indecomposable substances must be 
considered as simple matter furnished by nature. By far the greater number 
of mineral bodies are, however, not simple substances, but combinations of 
two or more such elements, in definite proportions, and in most cases even 
of a definite external form. Such compound bodies, to whose true character 
chemistry furnishes the only clue, are known as definite chemical combi- 
nations. On the surface of our earth, for ages exposed to the alternating 
influence of volcanic heat, of water, and of oxydation, we find these definite 
chemical combinations of elementary matter, united in the most varied 
manner and proportion, by mechanical agencies. These mixtures, then, 
which exhibit no definite proportion, by weight, of the different constituents, 
are excluded from the department of mineralogy. From this statement, we 
may more clearly see the intimate connexion between chemistry, mineralogy, 
and geology, as already hinted at. When we separate mineralogy from 
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