Four centuries have elapsed since Conrad Gesner published the first modern bibliography of bibliographies in the Pandectae of 1548. Although it was only a section in a general subject index, it shows Gesner's clear understanding of the task and a competent choice and arrangement of materials. Few later efforts have been equally successful. His definition of a bibliography is both narrower and broader than the one that has since found general acceptance. He does not include, for example, biobibliographical accounts of religious orders and nations. He was familiar with them but probably looked upon them as historical rather than bibliographical compilations. Like most later bibliographers, he does not include publishers' catalogues and catalogues of books owned by institutions and individuals. In 1598 Israel Spach employed what is virtually the modern definition of a bibliography. Like Gesner, he includes bibliographers who wrote in classical times. In 1628 Francis Sweerts almost takes the decisive step of making an independent list composed of bibliographies of bibliographies. The three folio pages in his Athenae Belgicae on which this list appears have no organic connection with that biobibliographical dictionary. Sweerts includes, furthermore, no ancient bibliographers. His work has a modern look.

In 1643 the bibliography of bibliographies comes of age with the announcement of Jodocus a Dudinck, Bibliothecariographia. The book is lost or more probably was never published, but its subtitle shows a clear comprehension of the nature of a bibliography of bibliographies. Philip LabbÉ published a bibliography of bibliographies in 1653 and a new edition of it in 1664. His loyalty to Catholicism and his exclusively French associations hindered its wide acceptance and use. Few of his contemporaries understood what he had done, and few learned how to use his book. Even Antoine Teissier, who revised and enlarged it, showed an imperfect understanding of its nature. The age was not ready for a bibliography of bibliographies. Cornelius a Beughem, a man of many bibliographies, may have perceived the situation, for he never published the compilation that he had announced in 1680. With the publication of a supplement to Teissier's revision of LabbÉ, efforts to make a bibliography of bibliographies came to a dead stop in 1705. They had resulted in a formulation of the task.

After 1705 no bibliography of bibliographies appeared for more than a century. The fragmentary tradition of listing books entitled bibliotheca, i.e. bibliography or catalogue, that might have led to one produced only withered shoots and ended in 1758 with Durey de Noinville's wretched compilation. During the eighteenth century the bibliography of bibliographies is, at best, only a chapter in surveys of learning. No doubt the great encyclopedias of the time satisfied scholarly demands so well that men did not perceive the place that a bibliography of bibliographies might fill.

Conrad Gesner, whom I regard as the first modern writer of a bibliography of bibliographies, aimed at comprehensiveness and included works of all ages as far as they came to his knowledge. He named Amphicrates and his contemporary Jakob Rueff in the same list without making a distinction between them. Almost immediately the bibliography of bibliographies became a guide to currently useful reference works and it has retained that function. Writing in the early years of the seventeenth century, Paul Bolduan and Francis Sweerts took a step away from comprehensiveness. They included no classical Greek and Latin authorities and very few medieval ones. This exclusion of classical writers runs parallel to the similar treatment of classical writers of history. In a list of classical historians we no longer cite Xenophon and Caesar along with Grote and Gibbon. No one thinks of naming a bibliographer like Cicero, Suetonius, or St. Jerome in the company of Petzholdt and Brunet. Although this rejection of ancient bibliographers began in the early seventeenth century, neither LabbÉ in 1664 nor Teissier in 1705 fully accepted it.

By 1812 we find a completely modern conception of bibliography. Gabriel Peignot cites no bibliographer from classical times and names only such older writers of the Renaissance as have not been superseded by more recent authorities. This definition of the bibliography of bibliographies makes it practically useful to the writer's contemporaries. With the exception of Theodore Besterman, the subsequent writers of bibliographies of bibliographies have been practical men who see a modern librarian's needs and more especially, when that functionary is invented, the needs of a reference librarian. Julius Petzholdt admits many old bibliographies to his Bibliotheca bibliographica of 1866, but gives them room only for historical reasons or in the absence of a modern work. Joseph Sabin goes somewhat farther by restricting himself to British and American bibliographies with only a side glance at those in other than European languages. LÉon VallÉe, Henri Stein, W. P. Courtney, and those who come after show a more and more definitely acknowledged restriction to modern works and especially those within the easy reach of their readers. The bibliography of bibliographies becomes an ever more skilfully fashioned key to unlock modern learning and modern libraries. In the last two generations cooperative effort has become characteristic of much bibliographical work and the publication of periodical surveys limited to brief periods and cumulated for longer intervals reflect both the difficulty of the task and the emphasis on contemporary usefulness. The standards of accuracy and, within the limits that have been accepted, the standards of completeness have enormously improved.

This brief historical summary makes it plain that a bibliography is or, at least, it has become a reference work that gives a limited amount of information of a very special kind. It is immediately useful in an emergency and less likely to be helpful in surveying historically any particular field of study. A corollary is the fact that a bibliography of bibliographies will ordinarily give a student little or no new information about a subject with which he is familiar, but can be a valuable aid to him in an unfamiliar field. A student of Renaissance English literature will not consult a bibliography of bibliographies to learn of such works as the Cambridge Bibliography of English Literature or A. W. Pollard and G. R. Redgrave, A Short-Title Catalogue of Books Printed in England ... 1475-1640. He already knows them. He may be very glad to find the titles of bibliographies of theology, history, or science that meet his needs. He should consult, also, the older books that Besterman alone among modern writers of the bibliography of bibliographies is likely to cite. Joris Vorstius rightly emphasizes the fact that a bibliography of bibliographies serves primarily a reference librarian.[212] I should only enlarge upon his remark by saying that the older bibliographies of bibliographies are invaluable and all too little known aids to understanding the historical development of a discipline or the background of an earlier period.

With all their faults and insufficiencies—and what human works lack them?—bibliographies of bibliographies are very valuable aids to scholars. As an introduction to a strange field one will naturally consult only the most recently published examples, beginning with Julius Petzholdt, Bibliotheca bibliographica (1866) or perhaps even with Theodore Besterman, A World Bibliography of Bibliographies (2d ed., 1947-1949; 3d ed., 1955-). In studying the historical development of a discipline or subject one can neglect the four oldest bibliographies of bibliographies. Gesner's Pandectae, Spach's Nomenclator, and Bolduan's Bibliotheca philosophica are general subject bibliographies of a sort that I hope to discuss at another time. These books and Sweert's Athenae Belgicae contain little or nothing as far as bibliographies are concerned that cannot be more easily found in other books. With the sole exception of LabbÉ's Bibliotheca bibliothecarum, which was absorbed into Teissier's Catalogus auctorum, a student of the historical aspect of a subject must consult all the bibliographies of bibliographies printed after 1664. They are independent or almost independent compilations and supplement one another. Fortunately they are not extremely difficult to obtain. In consulting them the modern scholar should give thanks to those who have labored so diligently in his behalf.