ORGANIZATION OF THE SCIENCES 



ticular species of living bodies. Similar is the 

 contrast between chemistry and mineralogy, of 

 which the latter science is evidently founded 

 upon the former. In chemistry we consider all 

 possible combinations of heterogeneous mole- 

 cules, in all imaginable circumstances ; in min- 

 eralogy we consider only the particular combi- 

 nations which are found realized in the actual 

 past or present constitution of the terrestrial 

 globe, under the influence of special sets of con- 

 ditions. A circumstance which well illustrates 

 the difference between the chemical and the 

 mineralogical point of view, although the two 

 sciences deal with the same objects, is, that a 

 large proportion of the facts contemplated in 

 chemistry have only an artificial or experimen- 

 tal existence. So that, for example, a body like 

 chlorine or potassium may possess great im- 

 portance in chemistry by reason of the extent 

 and energy of its reactions and its affinities ; 

 while in mineralogy, on the other hand, it may 

 be of little importance, because it is but sel- 

 dom concerned in producing the natural rear- 

 rangements of molecules which it is the busi- 

 ness of mineralogy to explain. And conversely, 

 some such compound as granite or feldspar, 

 which fills a great place in mineralogy, may be 

 of little interest from the chemical point of 

 view. 



Of these two kinds of sciences, according to 

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