10. UNION LISTS OF SCIENTIFIC PERIODICALS 



The two most important lists of that kind are: 



J ) The Union List of Serials in Libraries of the United States and Canada ( New 



York, 1927, one very large quarto volume of 1588 p.). 



Registering some 70,000 journals and serials, of every kind, dead or alive, pub- 

 hshed in some 70 languages, and available in some 225 American libraries. Two 

 supplements have already appeared, bringing the list down to 1932. 



Second edition by the same editor, Winifred Gregory (3065 p.. New York 

 1943). This lists between 115 and 120,000 items. Supplement to the end of 1943 

 (New York 1945). 



2) A World List of Scientific Periodicals published in the years 1900-1921 (2 vols. 

 London 1925-27), hsting over 24,000 periodicals. Second edition for the years 

 1900-34 ( 1 vol. 794 p., London 1934). Item 2 is less comprehensive than 1 because 

 it is restricted to contemporary scientific pubhcations, it includes some 36,000 entries 

 in 18 languages (for statistics, see Isis, vol. 23, p. 578). A new edition is in prepa- 

 ration. 



These two lists are useful, first, to identify a certain journal, secondly, to find 

 in what libraries ( British or American ) sets of it are available, and, finally, to judge 

 of its importance, or at least of its popularity, by the number of sets available in the 

 English-speaking world. This last judgment is possible only in the case of publi- 

 cations which are not distributed mostly by gift or exchange. 



