In both the Authors' Catalogue and the Subject Index, brevity has been studied because of the economy, but more because of the much greater ease of reference to a short title catalogue. The custom of giving full titles, etc., under authors, and only references or very brief titles under subjects, has been reversed. A reader seeking a book of a known author, in the vast majority of cases, wants simply the number by which to call for it, and can find it much sooner in a brief title catalogue. In the rare cases where more is needed the class number refers instantly to all these facts on the cards. On the other hand, a reader seeking books on a known subject, needs the full title, imprint, cross-references, and notes, to enable him to choose the book best suited to his wants.
The Subject Catalogue is a full title Shelf List on cards and is for the use of the public. The Shelf List is a short title Subject Catalogue in book form, made of separate sheets laced into an Emerson binder, and is for official use. We thus have without extra labor, both full and short title Subject Catalogues and Shelf Lists. The public Authors' Catalogue is a printed volume; the official Authors' Catalogue or Index is on cards. As a result each of the public Catalogues is checked by an official Catalogue; each of the card Catalogues by a book Catalogue; each of the brief title catalogues by a full title catalogue--an advantage that will be appreciated by all librarians desiring accuracy of administration and catalogues.
The Arabic numerals can be written and found more quickly, and with less danger of confusion or mistake, than any other symbols whatever. Therefore the Roman numerals, capitals and small letters, and similar symbols usually found in systems of classification are entirely discarded and by the exclusive use of Arabic numerals in their regular order throughout the shelves, classifications, indexes, catalogues and records, there is secured the greatest accuracy, economy, and convenience. This advantage is specially prominent in comparison with systems where the name of the author or the title must be written in calling for or charging books and in making references.
Throughout the catalogues the number of a book shows not only where it is but what it is. On the library accounts the character of each person's reading is clearly indicated by the numbers charged, and the minutest statistics of circulation in any subject are made by simply counting the call slips in the check box, and recording the number against the class number in the record.
By the use of size numbers the greatest possible economy of space may be secured, for the size distinction may be made for every inch or even less if desired, and this without additional labor, as it will be seen that the size figure, when introduced, requires one less figure in the book number, and so does not increase the number of digits as would at first appear.
Parts of sets, and books on the same or allied subjects, are never separated as they are sure to be, sooner or later, in every library arranged on the common plan, unless it be frequently re-arranged and re-catalogued. The great expense of this re-cataloguing makes it impracticable except for a few very wealthy libraries. In this system the catalogue and book numbers remain unchanged through all changes of shelving, buildings, or arrangement. In addition to its own peculiar merits, this plan has all the advantages of the card catalogue principle and of the relative location, which have been used and very strongly approved by prominent libraries.
As in the card catalogue system, there is room for indefinite expansion without devices or provisions. Space is the only requisite and if the shelf room is exhausted, the floor space is equally good, except for the inconvenience of stooping.
Some prominent opponents of classed catalogues have admitted that the Subject Index, in deciding where to class a book at first, and where to look for it ever afterwards, has removed their strongest objections. Certainly it would be impossible to make an Index more cheaply or more easy of reference, it being a single alphabet, of single words, followed by single numbers.
These class numbers applied to pamphlets have proved specially satisfactory. The number is written on the upper left corner and the pamphlets are arranged either in pamphlet cases with the books on the same subject or on special shelves divided every decimeter by perpendicular sections. As each pamphlet is examined when received into the library, it is the work of a single moment to pencil on it its class number. There is no expense whatever incurred, and yet the entire pamphlet resources of the library on any subject can be produced almost instantly. The immense advantages of this plan over those in common use, both in economy and usefulness, will be appreciated by every librarian caring for a pamphlet collection. A catalogue of authors may be made on slips if desired. The pamphlets themselves are the best Subject Catalogue.
Though designed wholly for library use, the plan has proved of great service in preserving newspaper clippings in large envelopes arranged by class numbers; and more especially in taking the place of the common note-book and Index Rerum. Slips of uniform size are used with the class number of the subject written on the corner. Minute alphabetical headings are used under each class number, the slips being arranged in numerical order like the Subject Card Catalogue. Clippings and notes arranged in this way are at all times their own complete index, and have the same advantages over the common scrap and note-books that the Subject Catalogue has over the Accessions Book, in looking up the resources of the library on any given subject. Those who have tried this method are so enthusiastic in its praise that it seemed worthy of mention in this place.