136 DISCOURSE ON THE STUDY 



more consequence, it gives it a recognized exist- 

 ence in our own minds, as a matter for separate 

 and peculiar consideration; places it on a list for 

 examination ; and renders it a head or title, under 

 which information of various descriptions may be 

 arranged ; and, in consequence, fits it to perform the 

 office of a connecting link between all the subjects 

 to which such information may refer. 



(130.) For these purposes, however, a temporary 

 or provisional name, or one adapted for common 

 parlance, may suffice. But when a very great mul- 

 titude of objects come to be referred to one class, 

 especially of such as do not offer very obvious 

 and remarkable distinctions, a more systematic 

 and regular nomenclature becomes necessary, in 

 which the names shall recall the differences as well 

 as the resemblances between the individuals of a 

 class, and in which the direct relation between the 

 name and the object shall materially assist the so- 

 lution of the problem, " given the one, to determine 

 the other." How necessary this may become, will 

 be at once seen, when we consider the immense 

 number of individual objects, or rather species, 

 presented by almost every branch of science of any 

 extent ; which absolutely require to be distinguished 

 by names. Thus, the botanist is conversant with from 

 80,000 to 100,000 species of plants; the entomo- 

 logist with, perhaps, as many, of insects : the chemist 

 has to register the properties of combinations, by 

 twos, threes, fours, and upwards, in various doses ; 

 of upwards of fifty different elements, all distin- 

 guished from each other by essential differences ; 

 and of which though a great many thousands are 



