used at once for tuniiiiL;' to the proper paj;'c of the Subject liid(!x. This 

 is done by lookiny at the numbers at the top corners of the payes. 



If the reader remember tlie name of the Author of a paper on a 

 given subject, he will probably liiid it convenient to refer to the 

 Authors' Catalogue rather than to the Subject Catalogue. 



In the Authors' Catalogue the numbers placed within square brackets 

 at the end of each entry are Reg-istration numbers, and serve to 

 indicate the scope of each paper indexed. The meaning of these 

 numbers will at once be found by reference to the Schedule. 



lu case the abbreviated titles of Journals are not understood, a key 

 to these is provided at the end of the volume. 



Topographical Symbols. 



Many of the sections are sub-divided into a ninnber of sub-sections 

 by means of topographical symbols. These symljols are letters printed 

 in italics, and they are explained by the topographical classilication 

 contahied in the Schedules. The topographical symbols are not 

 intended to be used instead of registration numl)ers. 



