xn.] A LIBRARIAN'S WORK. 249 



taneously in 1861. The object of an alphabetical 

 catalogue like those above described is " to enable 

 a person to determine really whether any particular 

 work belongs to the library, and, if it does, where 

 it is placed." If you are in search of Lloyd's 

 Lectures on tJie Wave-Theory of Light, you will 

 look in the alphabetical catalogue under " LLOYD, 

 Humphrey." Now this alphabetical arrangement 

 is the only one practicable in a public library, 

 because it is the only one on which all catalogues 

 can be made to agree, and it is the only one suffi- 

 ciently simple to be generally understood. For the 

 purpose here required, of rinding a particular work, 

 an arrangement according to subject-matter would 

 be entirely chimerical. Nothing short of omniscience 

 could ever be sure of rinding a given title amid such 

 a heterogeneous multitude. Every man who can 

 read knows the order of the alphabet, but not one 

 in a thousand can be expected to master all the 

 points that determine the arrangement of a catalogue 

 of subjects, as, for example, why one of three 

 kindred treatises should be classed under the rubric 

 of Philosophy, another under Natural Religion, and 

 a third under Dogmatic Theology. 1 But while it 



1 See the excellent remarks of Professor Jevons in his Principles 

 of Science, ii. 401. 



