INTRODUCTION. 



Sect. 1. Of the Classificatory Sciences. 



THE horizon of the sciences spreads wider and 

 wider before us, as we advance in our task of 

 taking a survey of the vast domain. We have seen 

 that the existence of Chemistry as a science which 

 declares the ingredients and essential constitution 

 of all kinds of bodies, implies the existence of 

 another corresponding science, which shall divide 

 bodies into kinds, and point out steadily and pre- 

 cisely what bodies they are which we have analyzed. 

 But a science thus dividing and defining bodies, is 

 but one member of an order of sciences, different 

 from those which .we have hitherto described; 

 namely, of the classificatory sciences. Such sciences 

 there must be, not only having reference to the 

 bodies with which chemistry deals, but also to all 

 things respecting which we aspire to obtain any 

 general knowledge, as, for instance, plants and 

 animals. Indeed it will be found, that it is with 

 regard to these latter objects, to organized beings, 

 that the process of scientific classification has been 

 most successfully exercised; while with regard to 

 inorganic substances, the formation of a satisfactory 

 system of arrangement has been found extremely 

 difficult; nor has the necessity of such a system 

 been recognized by chemists so distinctly and con- 



