CLASSIFICATION. 317 



respecting it as the case admits of, by merely being 

 told its name. 



There are two modes of giving to the name of a 

 kind this sort of significance. The best, but which 

 unfortunately is seldom practicable, is when the word 

 can be made to indicate, by its formation, the very 

 properties which it is designed to connote. The name 

 of a kind does not, of course, connote all the proper- 

 ties of the kind, since these are inexhaustible, but 

 such of them as are sufficient to distinguish it ; such 

 as are sure marks of all the rest. Now, it is very 

 rare that one property, or even any two or three pro- 

 perties, can answer this purpose. To distinguish the 

 common daisy from all other species of plants would 

 require the specification of many characters. And a 

 name cannot, without being too cumbrous for use, 

 give indication,, by its etymology or mode of construc- 

 tion, of more than a very small number of these. The 

 possibility, therefore, of an ideally perfect Nomencla- 

 ture, is probably confined to the one case in which we 

 are happily in possession of something nearly ap- 

 proaching to it ; I refer to the Nomenclature of Che- 

 mistry. The substances, whether simple or com- 

 pound, with which chemistry is conversant, are Kinds, 

 and, as such, the properties which distinguish each of 

 them from the rest, are innumerable ; but in the case 

 of compound substances (the simple ones are not 

 numerous enough to require a systematic nomencla- 

 ture), there is one property, the chemical composition, 

 which is of itself sufficient to distinguish the Kind; 

 of itself a sure mark of all the other properties of 

 the compound. All that was needful, therefore, was 

 to make the name of every compound express, on the 

 first hearing, its chemical composition; that is, to 

 form the name of the compound, in some uniform 



