Preface. 



knowledge and long experience in the handling of books 

 on science and technology, but is also keenly interested 

 in the cataloguing of them. Mr. Passenger undertook 

 the task of making on a uniform plan a card catalogue of 

 the full details of such books in the lists of British 

 publishers ; and the Committee is much indebted to him 

 for the care and attention he devoted to this work. In 

 order to secure uniformity in the bibliographic particulars, 

 it was necessary to invite the assistance of publishers, and 

 the Committee is glad to acknowledge that this aid was 

 readily given. It has thus been possible to state, for 

 each volume in the Catalogue, the author's name, title of 

 book, size of page, number of pages, date of last edition, 

 name of publisher, and price at the time (April, 1921) 

 when the Catalogue was sent to the printers. 



The volume contains more than six thousand titles, 

 and their satisfactory classification required careful con- 

 sideration. About fifty main groups were eventually 

 decided upon and these were divided into nearly five 

 hundred sub-classes. Even when a scheme of classification 

 had been formed it was frequently difficult to determine 

 under which head to place a book, but the Committee 

 was fortunately able to secure additional assistance in 

 accomplishing this task and desires to express grateful 

 thanks for it. Prof. J. H. Ashworth, F.R.S., classified 

 the titles of biological books, Miss M. S. Aslin those on 

 agriculture, Prof. H. Wildon Carr dealt with books on 

 philosophy and Miss M. Punnett and Prof. T. P. Nunn 

 with those on mathematics. Other titles were classified 

 by members of the Committee. 



The classification adopted is such that, so far as prac- 

 ticable, related subjects are placed near one another ; and 

 under each head or sub-head the titles are arranged 

 alphabetically according to author's names. It is thus 

 possible to see at a glance the volumes available in any 

 branch of science and technology. Following this 

 natural order, there is an aphabetical list of authors' 

 names, and a subject index, which should be of service in 



viii. 



