344 Darwinism and Other Essays. 



before this new catalogue can become the index 

 to all the treasures of the library. 1 



Another great undertaking was begun simul 

 taneously in 1861. The object of an alphabetical 

 catalogue like those above described is &quot; to enable 

 a person to determine really whether any particu 

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

 where it is placed.&quot; If you are in search of 

 Lloyd s &quot; Lectures on the Wave-Theory of Light,&quot; 

 you will look in the alphabetical catalogue under 

 &quot; LLOYD, Humphrey.&quot; Now this alphabetical ar 

 rangement 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 sufficiently simple to be generally under 

 stood. For the purpose here required, of finding 

 a particular work, an arrangement according to 

 subject-matter would be entirely chimerical. 

 Nothing short of omniscience could ever be sure 

 of finding 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 de 

 termine the arrangement of a catalogue of sub 

 jects, as, for example, why one of three kindred 



1 About seventeen thousand of these old titles were added during 

 the two years ending in July, 1877. 



