Doing Research at the Library of Congress

IX. Subject Searching for Pre-1968 Books: The Old Card Catalog

Not all of the books in the Library's collection are listed in the computer catalog. The retrospective conversion of the old card catalog to online form was done in the 1980s by a private company, not by the Library of Congress. These retrospective records are often not as complete or accurate as those created by the Library. The online catalog, as it is now, consists of two merged files. The first, composed of MARC records [MAchine Readable Cataloging], is the part produced by the Library itself; it covers acquisitions from 1968 forward, and is generally complete and reliable. The second file, called PREMARC, is the part that most corresponds to the old Main Card Catalog; it lists all books cataloged by the Library up through the end of 1980. (It thus overlaps with the MARC coverage.)

The PREMARC file is incomplete in several respects. It does not record all of the older books to begin with; thousands were simply omitted by the contractor. (The Library accepted these records realizing that they were a "first step" towards retrospective conversion, rather than a finished product.) PREMARC also does not contain the full information recorded on the original cards: as a rule, subtitles, contents notes, and series statements were not keyed in. Further, the entire (and very elaborate) system of crossreference cards in the old catalog is missing from the PREMARC file; and current cross-references do not pick up most of this older information. (These provide links among changes or variations in name forms; they also connect related subject headings.) This database also contains millions of typographical errors and misspellings--all of which adversely affect keyword searching. Indeed, it is the experience of the book-service division, which retrieves the books for readers, that over 15 percent of the PREMARC call numbers are incorrectly entered. (Note that many "Not On Shelf" problems for older books can be solved simply by checking the accuracy of a call number derived from the computer against the number given in the card catalog.) The Library has done some "global" corrections of several problems in this database, and is correcting other errors as reported; but for the foreseeable future it is best to regard the PREMARC file as not merely a change in the format of the old catalog records, but a significant modification (and diminution) of their content as well.

The biggest problem with PREMARC records is that they have unpredictable and nonstandard subject headings. The MARC records (the 1968+ part of the catalog) all use the current headings from the latest edition of the Library of Congress Subject Headings list; but the pre-1968 records in PREMARC do not. They use all of the old and outdated headings of the first nine editions of LCSH--Aeroplanes (rather than Airplanes), Woman (rather than Women), Ceylon (rather than Sri Lanka) and so on, and often mix both obsolete and current forms. The subject headings are not standardized or predictable for the pre-1968 records in the online catalog.

The Main Card Catalog (MCat), in contrast to the PREMARC database, uses the subject headings of the 9th edition of LCSH consistently; this was the edition in use at the time we stopped filing cards in the catalog (at the end of 1980). PREMARC uses all of the obsolete headings from the 1st through the 9th editions, inclusive. For example, when the obsolete heading Aeroplanes was changed to Airplanes, the cards in the Main Card Catalog were all revised to file under the new heading. The many changes and updates of subject heading forms were not made in the Library's Shelflist catalog, however; and it was the Shelflist rather than the Main Card Catalog itself that was keyed in to form the PREMARC database. (The Shelflist was another card catalog, in which cards were arranged solely in call number order--not by author, title, and subject. The Shelflist recorded subject headings only in the tracings field at the bottom of the card records. The obsolete headings in these fields were never updated because, in the card format, they were never intended to be searchable within the Shelflist; and no one anticipated a future age of computerization that would make them directly accessible.)

You can do systematic subject searches for the pre-1968 book records in the Main Card Catalog if you use the 9th edition of the Library of Congress Subject Headings list. This is a two-volume set, and multiple copies are available in the card catalog area. (Keyword searching in PREMARC does not solve the problem of its inconsistent subject headings, especially since the skeletal online records have so few searchable keywords to begin with.) The cross-reference structure of the 9th edition, however, does not use the Used For (UF), Broader Term (BT), Related Term (RT), and Narrower Term (NT) designations of the current list. The old cross-references are these:

There is no single indication of RT, but cross-reference terms listed under both sa and xx simultaneously are, functionally, RT terms.

Records in the Main Card Catalog are filed by author, title, and subject heading all in one alphabetical sequence. Note especially that subject cards are tinted red at the top, so that they will stand out from author and title cards. Subject headings are also distinguished from author and title filing lines by the fact that subjects are printed in ALL CAPITAL LETTERS, whereas author and title entries appear in conventional upper and lower case type.

One of the most valuable features of the old card catalog is its huge network of cross-references. Often these indicate name changes in corporate or governmental agencies; or they indicate which form of an author's name is used as the standard; or they link broad subject headings to narrower terms by sa [see also] references. These linkages do not appear in any computer database, nor are they fully reflected in the printed 9th edition of LCSH. The rule is this: be sure to pay attention to any cross-reference cards you see in the old card catalog.

The alphabetical filing sequence of the cards is not the same as the sequence used in the computer catalog, and is also different from the letter-by-letter sequence that many readers intuitively expect. The cards use a modified word-by-word order; the difference may be illustrated as follows:

One problem that readers often have with this sequence lies in mistakenly looking for things (subjects or titles) within the first two filing sequences of persons and places, which can often extend for a whole drawer or more. Subjects and titles appear only after persons and places (starting with the exact same word) are finished.

Note that any change in the first word of a phrase starts a new sequence. In the list above, Orangeburg, S.C. [a place] follows rather than precedes ORANGE JUICE [a thing] because it has a different first word. Again, the basic filing is word-by-word, not letter-by-letter; but the former sequence itself has further subdivisions in the order of persons, places, and things. Note that in the five hundred drawers with cards filed under United States the term as a corporate body [treated as a person] files ahead of the same term as a subject, which in turn files ahead of the same two words as a title. (Don't be shy about asking the librarians for help in using the United States drawers--or any other parts of the catalog that confuse you.)

Note, too, that subject cards for family histories file alphabetically after the last personal name in the sequence. Thus SMITH FAMILY files after Smith, William and Smith, Zebulon but still within the persons subgroup, ahead of either places or things.

The Main Card Catalog (MCat) is physically located behind Alcoves 6 (A through P) and 7 (P through Z) adjacent to the Main Reading Room. Note that there is also a second, smaller card catalog ahead of the letter A in the Main Catalog; this smaller A to Z sequence is the Periodicals Card Catalog (PCat). The latter is essentially a duplicate listing of most of the periodical titles filed in the MCat, segregated into its own sequence for easier consultation. (It is often difficult to locate periodical titles in the Main Catalog because of the complexity of the filing sequence.) In other words, if you are looking for an old periodical title that does not show up in the computer catalog, look first in the Periodicals Card Catalog. If, however, you do not find the title you want there, then be sure to double-check the Main Card Catalog itself. Not all of the old periodicals included in the MCat are duplicated in the Periodicals Catalog. Further, since filing continued in the PCat until about 1983, it contains some titles not in the MCat at all.

In any event, remember this: if you do not find a title you are looking for, for whatever reason, be sure to talk to a reference librarian. The Library has many periodical titles that show up in neither of the two card catalogs--nor in the computer catalog. (Microform sets contain many such titles; and some electronic journals are not listed in conventional places.)