The list of subject headings issued by the Library of Congress is used
also, for reference and comparison, by many other libraries throughout
the country. It has been suggested that a statement in regard to the
purpose, scope, and manner of printing of the list, might be useful to
the librarians receiving it, and possibly valuable as well to others
who are interested in the undertaking, and who may be, to some extent,
unfamiliar with the Library of Congress catalog.
The printing of the list of subject headings was begun in the summer
of 1909. Up to that time, the second edition of the A. L. A. subject
headings had been used as a basis for the subjects assigned in the
Library of Congress catalog. But so many additions and alterations had
been made in our interleaved copies of the A. L. A. list, that the need
of an entirely new list of headings began to be urgently felt, although
the difficulty had been partially obviated by the printing of lists of
additions to the old A. L. A. list, for distribution to the catalogers
at the Library of Congress. At this date the third edition of the A.
L. A. list was already in preparation, yet it was considered wiser
to print a list of the Library of Congress headings, rather than to
co-operate in the A. L. A. undertaking, as the headings needed in our
catalog differed to such an extent from those required for the average
public library.
The distribution of the list to other libraries was not, at first,
contemplated. The printing of the subject headings was undertaken to
facilitate the work of the catalogers in the Library of Congress,
and it was believed that, if supplied to other libraries in its
preliminary form, the list would give rise to many queries in regard
to unavoidable omissions and inconsistencies. It had not progressed
far, however, before many libraries intimated that it would be useful
to them to receive the letters as they were issued, and when requests
became too urgent for refusal, it was decided to supply copies at a
price insuring that only those libraries should order them which had
serious use for them. It was considered that 50 copies for distribution
outside the Library of Congress would surely be sufficient, but it
turned out that the estimate was too small, and, in consequence, there
has had to be much reprinting of the early letters of the alphabet. The
edition of the letter P, just issued, was 500 copies.
The scope of the list of headings is largely inclusive in its
character, covering subjects in all branches of knowledge as far as
they have been adopted in the Library of Congress catalog. The names
of persons and places are, however, omitted, also names of societies,
institutions, and bodies of various kinds, names of treaties and
conventions, and systematic names of genera and species in botany and
zoology.
The classes theology, and military and naval science are only partially
represented in the list, as these sections are not yet re-cataloged.
The classes language, literature, and philology, which are now in
the process of recataloging, are more fully, but not yet wholly,
represented. In the earlier letters of the alphabet, few headings in
law were introduced (as it has only been during the past few months
that the law headings have been systematically considered), but they
are now included in the list, and many of those omitted in the earlier
letters are being entered in the lists of additions to the subject
headings issued in connection with the main list.
We include in the list the more important subdivisions under a subject.
These subdivisions are printed in italics, and separated from the
main subject by a dash. One point to which I would especially call
the attention of librarians using the list is that ordinarily only
those subdivisions are printed under a subject which are distinctive,
or peculiar to that subject. General form subdivisions, such as
Directories, Periodicals, Societies, etc., which may properly be used
under any subject requiring them, are, as a rule, omitted from the
list. (A list of these form subdivisions can be found on p. 19 of the
"Preliminary list of subject subdivisions," issued by the library in
1910.) Under names of countries only the history subdivisions are
included.
Turning now from the consideration of the subdivisions, a few words may
be useful in regard to the cross-references from subject headings to
related subjects. In general, it may be said that references are made
from the more inclusive to the smaller subjects, and not ordinarily
back from smaller to larger. We should refer from Grain to Maize and
Rye, but not from Maize and Rye back again to Grain. Where practicable,
references are made from the most inclusive to somewhat more limited
subjects, and from these latter to subjects still more specific, rather
than from the inclusive to the specific subjects. We refer from Art
to Engraving, from Engraving to Stipple-engraving, not directly from
Art to Stipple-engraving. These general principles have been departed
from where it has seemed expedient, the desire being to render the list
useful and practical, rather than to make it adhere too strictly to
rigid rules of procedure.
The seeming incompleteness of references from many subjects, references
which obviously are needed to round out the various aspects of subjects
is due to the fact that certain headings are not as yet introduced in
the Library of Congress catalog. We have been very conservative about
introducing new headings until called for by the books in hand, judging
that the headings should be made to conform to the literature, rather
than the literature to the headings.
The printing of a subject in antique type indicates that, in the
library catalog, the subject has country subdivision, as in Education,
Labor and laboring classes, Insurance, etc. It may be helpful to add
here that the country is subordinated to the subject in our catalog,
when it seems desirable to keep the material on a topic together,
rather than to distribute it under the country headings. This includes
many subjects in technology, science, art, and the social sciences.
The numbers which follow the subject headings indicate where the
material dealing with those subjects is classified in the Library of
Congress. The explanatory words following these numbers serve merely
to guide those interested in the classification scheme. They are in
different form from the subject headings, and should not be confused
with them. In the matter of hyphens, the Century dictionary has been
used as an authority.
At the present time the list of headings has been completed through the
letter P. Q and R are now ready for the press, and will probably be
issued in the course of a few weeks. The editor of the list sometimes
feels it to be a cause for gratitude that the English alphabet is
composed of only 26 letters. Should it contain as many letters as some
other alphabets, the Sanskrit for example, the day of completion of the
list might indeed be far away.
A few words in regard to the printing of the lists known as "Additions
and corrections" will, I think, be needed for a full understanding of
the subject headings. I have already spoken of the lists of additions
issued in connection with the old A. L. A. list, before the Library
of Congress list of headings began to be printed. When letter A of
our new list was ready for press, there had been four of these lists
issued, the additions being cumulated in each successive number. The
corrections in the lists appeared but once, and were carried over by
the catalogers to copies of the A. L. A. list. The headings in these
early supplementary lists have, of course, been incorporated in the
Library of Congress list, as far as the letters have been printed.
Even after the new list was begun, it was found impossible to dispense
with the "Additions and corrections" lists, as the library catalog grew
and expanded. We have continued to issue them from time to time, as
occasion has demanded, and have included in them new headings in the
section of the alphabet not yet printed, as well as additions to the
letters which have already appeared in print.
Each "Additions and corrections" list is cumulative, as far as the
additions are concerned, so that a library possessing the main list and
the latest supplementary list has a complete record of all the Library
of Congress headings which have been printed. As was the case in the
lists supplementary to the A. L. A. headings, the corrections noted
appear but once, and should be carried over by catalogers to the main
list of subject headings.
The classification numbers, and cross references to related
subjects, known as the "See also" references, are not included in
the supplementary lists. Direct "See" references from one subject to
another, or from one form of name to another, are, however, usually
included, that the cataloger may avoid the pitfalls lurking for the
unwary.
Including the early supplementary lists, there have been, up to the
present time, eight lists of "Additions and corrections" issued, and
number 9 is ready for the press.
Having now touched upon some general features in regard to the issuing
of the list of subject headings, with its supplementary lists, I will
conclude with a word as to a later and fuller edition. The list now
being issued is a preliminary list, printed as manuscript, and, to some
extent, experimental in its nature. While it is being made as complete
and inclusive as present conditions seem to warrant, the intention
has been to reissue it later in book form, wider in its scope and
more inclusive in its references. Concerning the date of issue of the
fuller edition, should this desired consummation be brought about, it
is impossible at this time to make a statement. Probably it will be
best to wait until the remaining classes of books in the library are
reclassified and re-cataloged, before any definite decision as to date
is reached.
It has been suggested that the next edition of the list might be put
into loose-leaf form, with a view to keeping it to date by inserting
new leaves, when necessary, in place of old ones. Experiments may
be tried along this line, and the relative merits of the various
loose-leaf binders investigated. The advocate of this plan suggests
that the Linotype slugs be kept standing, and that once a month the
sheets on which changes have been made be reprinted, and distributed to
the catalogers at the Library of Congress, and to subscribers to the
list.
The subject matter of a later list would doubtless agree with the
present list in general features, but some minor changes might be found
to be desirable. One point to which our attention has been called is
the possible advantage of entering subjects in zoology and botany in
the plural form rather than in the singular, as most of them have been
entered in the present list. Another matter which merits consideration
is the substitution of subdivided headings for the inverted forms now
in use in certain classes of subjects, as in the headings Oxygen,
Physiological effect of, and Man, Origin of. Some other questions to be
considered are as to whether it would be advisable to distinguish in
the list those subjects which are divided by country and then by city,
from the subjects which have direct local subdivision; whether certain
classes of headings now included could be advantageously dispensed
with; and whether the main subdivisions of the animal and vegetable
kingdoms are a valuable feature of the list.
Doubtless other matters will suggest themselves for consideration as
time goes on, and we shall hope eventually to publish a list which
may commend itself as a valuable tool to library workers. Borrowing
the words of Mr. Charles A. Cutter in the preface to his "Rules for a
dictionary catalogue" we may say with him: "It is to be expected that a
first attempt will be incomplete, and we shall be obliged to librarians
for criticisms, objections, or new problems, with or without solutions."
It had been hoped that Mr. J. C. M. Hanson would personally supplement
this paper by an informal account of the early practice and
experimentation of the Library of Congress. In his unavoidable absence,
brief extracts from a personal letter were read by Miss Thompson,
who then called upon DR. E. C. RICHARDSON, librarian of Princeton
university, to open the discussion with some previously prepared notes
on