PART V. 

 PHYSIOGRAPHY. 



. 253. DEFINITION. 



Physiography means the description of natu- 

 ral productions (. 17.). It is intended to pro- 

 duce a distinct image of those objects which we dis- 

 tinguish from each other by means of the Charac- 

 teristic, and denominate conformably to the rules 

 laid down in the Nomenclature. 



Physiography is not adapted to the purpose of distin- 

 guishing minerals. We cannot by its assistance find the 

 place of a given mineral in the system ; or, in other 

 words, recognise it : for it is independent of that con. 

 nexion among natural productions upon which systems are 

 founded, and considers them singly, every one by itself. 

 Physiography, therefore, cannot acquiesce in considering 

 single characters or characteristic marks ; but it must ex- 

 hibit them all, if the image it produces is meant to be a 

 complete and satisfactory one. Its difference from the 

 Characteristic, founded upon these properties, is as obvious 

 as the impossibility of substituting the one instead of the 

 other. A description, therefore, is not a character (. 242.) ; 

 since the peculiarity of every character consists in its 

 being composed of a smaller number of characteristic terms 

 than may be observed in the objects characterized. 



The descriptions presuppose nothing but Terminology. 

 It is perfectly indifferent what nomenclature is made use 

 of in Physiography, provided only the names and denomi- 

 nations to which the descriptions of the species refer, an- 

 swer the purpose of keeping separate those objects, which 



VOL; ii. A 



