GEOGNOSY AND GEOLOGY. 
Piates 37—53. 
Tue inanimate objects of our planet may be considered from two points 
of view, either in respect to their mathematical and physical properties, 
and chemical compositions, as individuals, or as forming parts of a whole, 
combined according to certain definite conditions. 
The science which treats of the inorganic components of our earth, from 
the first point of view, is that of Mineralogy, or Anorganology, while 
Geology has reference to the second mode of their consideration. Like 
astronomy, geology affords most sublime and elevated subjects of 
contemplation; and like it also, it has made astonishing progress within 
the last few decades. 
Geology is properly included under geography ; since by the latter, in its 
wider sense, we must understand the entire physical history and structure 
of the globe. 3 
Inanimate nature is presented to us under three points of view 
corresponding to the three conditions in which matter is aggregated: 
namely, as gaseous (the atmosphere), as liquid (the waters), and as solid 
(the land or solid portions). According to this difference in the aggregation 
of inorganic matter, we have the following divisions of geology : 
1. Atmospherology, or Meteorology. — 
2. Hydrology. 
3. Mineralogical Geology, or geology in its restricted sense. 
Like every other branch of the philosophy of nature, geology (in the 
above limited meaning) may be treated of in two ways, descriptively and 
historically. Hence the further subdivision into the descriptive portion, 
Geognosy, and the historical portion, Geogeny, or Geology in its most narrow 
signification. Geognosy furnishes us with ascertained and established facts. 
upon which, as a foundation, the theoretical superstructure of geogeny is 
reared. Hence it is evident that a study of the former must precede that of 
the latter; since it is only by the combination and comparison of facts, that 
logical conclusions and satisfactory theories become possible. Geognosy 
might then be understood as the account of the present peculiarities of the 
solid parts of the earth; but when we remember that our knowledge of the 
earth extends only to exceedingly minute depths compared with her entire 
radius, it were more modest in us to define geognosy as the account of the 
earth’s crust. It is to mining operations, particularly, that we owe our 
knowledge of this portion of the earth: at least it was this branch of art 
that first led us to the knowledge of certain laws of her structure. It is, 
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