How This Directory was Compiled
The editor's intention has been to gather information from the issues of each journal as well as from all available secondary sources in order to provide up to twenty six fields of information per title, and ultimately to obtain a photofacsimile title page for each entry. About six issues have been perused for each of some 10,000 titles, in British Libraries. We have been able to provide 9,000 title pages.
In practical terms, more bibliographical information is to be found about most titles within the secondary sources than within the issues of the periodical itself. This fact is explained by the very fluid nature of a periodical: most issues vary from each other in several key bibliographical identifiers: frequency, price, size, staff, departments, and so on, as listed in the section entitled Taxonomy. Moreover many bibliographical details, such as the proprietor, publisher, circulation, indexing and the publishing history, are rarely available within the pages of a periodical. So a good history of any one periodical may be much richer than any half dozen or so issues could ever be.
In preparing the first and second series the editor and his staff have read more than 6,000 secondary sources: catalogues, magazine articles, books, indexes, encyclopedia entries, sale records, advertisements, prospectuses, notes and queries, biographies, stamp returns. Often this material presents anomalies difficult to resolve--ones which can only be passed on to the reader who might find in them clues which the editor does not recognize.