PREFACE 



The present list, the third of this Library's bibliographical publica- 

 tions, is intended to make available the resources of the Library in 

 the field of subject bibliography so far as they are brought out in its 

 classed subject catalogue. Its scope is, of course, that of the Library, 

 and includes the social, physical and natural sciences and their applica- 

 tions. It gives not only the distinctively bibliographical works on each 

 subject, whether periodicals or monographs, but also works which contain 

 bibliographical material thought to be of interest either because of the 

 number of titles given or the minuteness of the subject treated. It in- 

 cludes also general indexes to periodicals covering more than two years, 

 whether the periodicals themselves contain bibliographical material or 

 not, and the catalogues of special libraries, which often are valuable as 

 bibliographies. The most serious omission is that of analytical references 

 to articles in periodicals and other serials. 



The inclusion of any given title must be a matter of judgment and this 

 is particularly so in the case of periodicals. Very many of them devote 

 a section to bibliography which varies from such a degree of fulness as 

 to make the periodical one of bibliography in all but name, to a mere 

 "Table of contents of other periodicals" or "List of books received for 

 review." At first the line was drawn more strictly in periodicals than in 

 books and even the periodicals devoted to abstracts were omitted, but upon 

 reconsideration it was decided to make the list more complete. When 

 this decision was made a large part of the volume had been printed, so 

 that a considerable number of such titles are included in the ADDITIONS, 

 page 421, which also contain the new titles prepared since the printing 

 of the list was begun. Although it has been printed in sections of eight 

 pages, occasionally the same title has been required in two places within 

 the same section; in such cases the more important place has been selected 

 for the main list, and the omitted title has been inserted in the other 

 place in the ADDITIONS. 



The arrangement of the list is the same as that of the section 016 of 

 the classed catalogue, and it contains practically all entries in this section. 

 The order within each smallest subdivision is chronological, the latest work 

 being put first, but as only the more important of these subdivisions could be 

 given in the headings, though all are brought out in the index, the reasons 

 for arrangement under each heading are not always evident. Peculiarities 

 of typographical arrangement have been determined largely by the pre- 

 vious use of the same matter on printed catalogue cards, the type for 

 which has been electrotyped. Inconsistencies in the form of entry are 



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