One of the most revolutionary developments in scholarly communication is the enterprise that puts the catalogs of the nation's libraries into the hands of researchers seated in local libraries or even in front of their own personal computers. Networks of American libraries have compiled union catalogs in electronic form that are so comprehensive and widely available that they can be termed national online bibliographic databases.

Online union catalogs surpass card catalogs in flexibility and usefulness: they offer more indexes or access points for searching the bibliographic records; frequently subject access is better because more words can be used as search terms; some have browsing capabilities; and they list the member libraries that hold each item. Besides being used for such technical purposes as cataloging and acquisitions, these databases are used by librarians and patrons for locating specific works, verifying bibliographic citations, compiling author and subject bibliographies, and researching the history of books and publishing. At present, complex search routines, strange-looking records, and limited resources for equipment and training of library patrons restrict use of the databases in most institutions to librarians, but current projects by the database producers are making them both more useful as research tools and more easily accessible to individual scholars.

The two online union catalogs that qualify as national bibliographic databases are the Online Computer Library Center Online Union Catalog (OCLC for short) and the Research Libraries Information Network database (RLIN, pronounced ar-lin). Both these databases are owned and operated by non-profit corporations that began as cooperative cataloging networks but soon expanded to activities in sharing resources, reducing processing costs, and improving access to member libraries' collections. Originally the two networks served a different constituency of users and types of libraries, but with the growth of the organizations both now have programs especially for research libraries and both databases include research collections. The databases are available to libraries directly from their respective network corporations or through regional library networks and library service agencies. Both include all Library of Congress cataloging that is in machine-readable form regularly updated, plus the cataloging and holdings data from contributing libraries. Records in the databases represent either formats of materials: books, serials, maps, archival and manuscript materials, visual materials, sound recordings, musical scores, and machine-readable data files. Both databases have an interlibrary loan system to facilitate sharing resources among member libraries. Both are richly enhanced with records from retrospective conversion projects that convert older cataloging into machine-readable form and catalog heretofore uncataloged works, including archival material, manuscripts, and special collections. These cooperative ventures supported by a number of libraries and governmental and private funding sources frequently also include conservation of the original material, microfilming, or both.

OCLC, the older of the two networks, began in 1967 as the Ohio College Library Center and put its database online in 1971. It is now international in scope having almost 8,000 member libraries of all types in twenty-six countries. The online catalog has approximately eighteen million bibliographic records for the eight types of materials. Among the records more than 300 languages are represented and more than 260 million locations of items are recorded. Personnel at each of the member libraries can search the database for specific works by author, title, or certain code numbers; direct use by the individual patron is not usually permitted.

The OCLC database has an ever-expanding store of bibliographic and location information provided by the cataloging of new materials received regularly from the Library of Congress and member libraries, by the conversion of older catalog records, and by OCLC-sponsored original cataloging of some collections of older materials. Among its most notable projects of interest to historians is the U.S. Newspaper Program, supported by the National Endowment for the Humanities, in which the Library of Congress and libraries, archives, and historical societies in twenty states and territories enter into OCLC their cataloging and holdings data for U.S. newspapers dating from the seventeenth century. Major microform sets such as the Wing Short Title Catalog and the American Periodicals series have been cataloged at the specific author and title level so that researchers can find the individual items in the magazines in the collection.

Joint projects of OCLC and its libraries, supported by grants from the National Endowment for the Humanities, the U.S. Department of Education, and private foundations, catalog and preserve rare and unique older materials and add the records to the database. A sampling of these projects includes the cataloging and preservation of about 17,000 eighteenth-century imprints in philosophy and religion of Emory, medieval Slavic Cyrillic Manuscripts at Ohio State, and the Cutter pamphlet collection of social and cultural history ephemera, 1854-1966, at the State Historical Society of Wisconsin. In 1987, 835,000 cards from UCLA's libraries were converted to OCLC records, including the Clark Library shelflist. Several current projects will add their bibliographic records to both the OCLC and RLIN databases: about 50,000 records from the University of California Bancroft Library collections of rare books and Western Americana; pre-1800 imprints in English history, politics, religion and law at the University of Missouri-Columbia; and about 60,000 records from the Center for Research Libraries. Some of the special collections cataloged in OCLC are described in the clear and lively Guide to the OCLC Database and the Special Collections Therein (Dublin, OH: OCLC, 1984).

The OCLC Research Libraries Advisory Committee addresses matters of concern to the member research libraries. For example, this group recently developed the Reciprocal Faculty Borrowing Privileges, a library card, dubbed a "scholar's passport," that gives faculty members on-site physical access to collections in the libraries of the sixty institutions that have agreed to participate, including the universities of California at Berkeley, Irvine, Riverside, and San Diego; the universities of Illinois, Indiana, Texas at Austin; and the Newberry Library.

In accord with its purpose of furthering access to and use of scholarly information and spurred by new and better technology, increased demand for services, and the existence of a rival enterprise (RLIN), OCLC is introducing system improvements and new products. Portions of the database, for example educational materials, are available on compact discs for library patrons to search without the complications and charges of the online catalog. A system to store large reference works and compact discs, search and display text, zoom to enlarge specific areas, and print pages on site has not yet been applied to works of interest to most historians but could be if there were sufficient demand. Another pilot project is to store books online at OCLC, allow users to search the table of contents and index pages, then request the desired text and graphics. The most widely useful improvement, however, will be the completely new, easier-to-use, as well as transmission of textual and graphic data.

The second of the two national online bibliographic databases, RLIN, has a main bibliographic of catalog database and additional specialized databases; altogether it has about twenty-eight million records for the eight formats of materials in more than 80 research and special libraries and archival repositories. RLIN belongs to the Research Libraries Group, Inc. (RLG), which is owned and operated by thirty-six universities and research institutions; fifty-five associate members participate in some of its programs; and several hundred more libraries use the database for cataloging and reference. RLG was founded in 1974 to solve some problems of large research libraries not then being addressed by OCLC. In 1978 it acquired Stanford's automated cataloging system for the basis of its online database and named it RLIN.

RLIN lists all books cataloged by the Library of Congress and RLG libraries since 1974 and receives regular additions of records from those sources, including records from the British National Bibliography. RLIN, like OCLC, has pursued a number of retrospective conversion and archival projects with the support of its member institutions and outside funding. In 1987 a three-year, twenty-library project added more than 450,000 records. The American Antiquarian Society added almost 32,000 records, including broadsides, books, and pamphlets from the seventeenth, eighteenth, and early nineteenth centuries. Also in 1987 University Microfilms International contributed 95,000 records for microforms, primarily in western history and culture. The archive and manuscript file in RLIN has nearly 130,000 records for primary source materials at libraries, museums, state archives, and historical societies, including, for example, the SPINDEX records at Cornell and the Minnesota Historical Society converted to the standard machine-readable format and added to the database, and more than 25,000 records from a seven-state archives project funded by the National Historical Publications and Records Commission.

In addition to the main catalog RLIN has several specialized databases: the Avery Index to Architectural Periodicals, which indexes journal articles, online since 1980; SCIPIO, the database of art sales catalogs dating from 1599 to the present; and, probably of most interest to historians, the Eighteenth-Century Short Title Catalog (ESTC). The ESTC describes publications printed in Great Britain or its colonies and publications printed in English anywhere in the world, 1701-1800. Currently it has some 200,000 records, expected to grow to 400,000 by the mid 1990s, which contain bibliographic data and locations in nearly 1,000 libraries for books, pamphlets, sessional papers of the House of Commons, advertisements, society membership lists, transport timetables, and other ephemera (but not theatre programs), some of which have never before been cataloged. Preliminary work on papers at the Public Record Office has begun. Items are indexed—and thus can be searched—by personal or corporate author's name, title word or phrase, place of publication, publisher, date, call number, and library location code. There is no subject indexing but all words in the titles may be searched, thus one can find drama printed in Belfast by asking for Belfast and the words play or drama or tragedy or farce or masque found in titles; or find items published in Philadelphia in 1776; or find all works with the word pope in the title and not authored by Alexander Pope. Searching has been explained at meetings of scholarly societies and at a conference at UCLA's Clark Library in 1987 (The Clark Newsletter 13 [Fall 1987]: 4)

RLIN plans to add more special research databases as they are evaluated for quality and usefulness. Two currently being developed are the Rutgers Medieval and Early Modern Data Bank for currencies, prices and wages, weights and measures, taxes, and other economic and demographic data drawn from printed sources, wills, and additional legal and administrative records;and, in conjunction with the Modern Language Association, the Research-in-Progress database of pre-publication information from journals in the humanities.

The special databases are so valuable to researchers that RLG has arranged for direct access to RLIN by individuals using personal computers; and eleven RLG member libraries are conducting a special program to facilitate RLIN use by individual faculty members. Information on how to obtain an RLIN account and searching instructions is available from the RLIN Information Center, telephone 800-537-RLIN.

Information professionals have called the RLIN search system, used in both the main database and the special databases like ESTC, simple to use in comparison with other systems. The uninitiated will probably not consider it simple, but it is sophisticated, flexible, and powerful. It permits retrieval on almost any word in the record—author, title word or phrase or related title, subject heading word of phrase, and a variety of other fields appropriate to the particular kind of material or special database, for example, U.S. government document number, international standard book number, genre code, sound recording label, and notes. The system allows the use of Boolean logic (and, or, not) so that a search may combine various words and indexes to expand or narrow the results. The truncation feature permits a search with incomplete information or a search for variations in a word, e.g. all words beginning with revolution to retrieve revolutions, revolutionary, and revolutionist as well as revolution itself. And RLIN has a browse command that is used to peruse a list of alphabetically adjacent words. for example, all the authors names Shakespeare or similarly spelled names.

An area that has attracted the attention of both OCLC and RLIN organizations is East Asian material. Noting that a majority of the major U.S. collections were in its member libraries, in 1983 RLG designed a computer code for Chinese, Japanese, and Korean characters (CJK) and engaged a company to manufacture specialized terminals for cataloging. In 1987 there were more than 337,000 CJK records in RLIN. IN these records data in the vernacular is repeated in romanized type so librarians at ordinary terminals can also use them. OCLC, too, developed a CJK cataloging workstation and is adding records in the vernaculars; for example, UCLA and cataloged some 2,400 rare Japanese fine arts titles whose subjects are of interdisciplinary interest. OCLC had received funding to work with the National Library of China (Beiging) to catalog materials from the Republican period, 1911-1949. Indiana University Library has installed an OCLC CJK terminal for faculty members and students to use to access records that contain vernacular scripts.

But why, one may ask, do we have two national bibliographic databases? Why don't the two merge their databases for more comprehensive and efficient service? The simple answer is history, which covers all the technical, political, philosophical, and organizational or bureaucratic reasons. Neither OCLC nor RLIN began as a national organization or intended to become one. They grew from regional and specialized cooperative networks: OCLC from an Ohio group and RLIN from a handful of eastern research libraries and Stanford. A number of other regional networks still exist as well, some brokering OCLC services and some with their own system. The fledgling networks had modest funding, not enough for a nationwide system; nor did the technology for a national system exist when they were founded. The networks all started at about the same time and, except for RLIN, grew on a geographical basis.. The organizational structure, ownership, and financing of OCLC and RLIN are different, as has been their interpretations of the proprietorship of their databases. OCLC, which began with an orientation toward public and smaller academic libraries, has grown to include many research library members and programs specifically for research libraries but still serves libraries of all types. RLIN continues its narrower focus on research and special libraries. Like most institutions once established, these two successful library network corporations strive to maintain their own identities and organizations. All the major networks—OCLC, RLIN, the Western Library Network, and the University of Toronto system (UTLAS)—have copied their competitors' techniques and services. Competition among them has undoubtedly fostered the development of services, more responsive and dynamic systems, and more cost-effective prices for services. Cooperation between OCLC and RLIN, begun in the early 1980's when OCLC rules were changed to allow libraries to be members of both networks, is being pursued in technical cataloging matters; eventually some bibliographic data may be exchanged between them.

At present, whichever system a library is fortunate enough to belong to offers historians the to tap into the catalogs of hundreds of libraries and archives in the United States and even some foreign countries—one's local library has the details. Scholars are reminded, however, of the limitations of these research dream machines. The databases do not list the entire holdings of all member libraries. Retrospective conversion and additional cataloging projects are awesome but still have not covered all the older works. The interlibrary loan systems of OCLC and RLIN are a tremendous boon to obtaining needed materials but sometimes are still too slow, and not every item listed can be borrowed or copied. Some researchers may find the lack of direct access to the databases inhibiting; some may be put off by the unfamiliar and arcane record format or annoyed by the differences in the ways each database can be searched. But researchers who, while recognizing the limitations of the particular database, learn how to exploit its capabilities will have undreamed of access to the vast resources of the nation's research collections.

Information in this report is based on newsletters, annual reports, brochures, and correspondence from OCLC, RLIN, and ESTC.

—Joyce Duncan Falk, an independent historian in Santa Barbara, California, was formerly Library Data Services Coordinator for the University of California, Irving.