Many books can be very properly put in any one of several different classes.  In which one a given book should be placed will often be decided by noting where other like books have been placed.  Books by authors of the same name will often fall into the same class, and to each of these a different author-number must be given.  You must have at hand, then, a list of the books already classified, to see at once, in classifying the next book, what kinds of books and books by what authors are in each class.  Every book in the library, as soon as it has been classified, and has received its proper author-number, should be entered in a list in the order first of its class-number, next of its author-number.  This list is called the shelf-list.  It is commonly kept on sheets, but many librarians believe it best kept on cards; a card for each different book.  It is a catalog of all the books in the library arranged in the order in which they stand on the shelves.  It is a subject-index of the library.  It is indispensable in the work of properly placing, class-numbering, and author-numbering new books.  It is a list from which it is very easy to check over the library and learn what books are missing or out of place.  It includes usually only the class- and author-number, author’s name, brief title, and accession number.  This last enables one to refer at once from the brief entry of a certain book in the shelf-list to the full information in the accession book.  There are advantages in adding to the shelf-list record the publisher and price.  As soon as a book has received its class- and author-numbers, which together are sometimes called the “call-number,” as being the mark to be used by the public in calling for a book, these numbers, or combinations of numbers and letters, should be written in the accession book in a column left for the purpose, on the line given up to the description of the book in hand.  This enables one to refer at once from the accession entry of a given book to the shelf-list entry of the same book.

[Illustration:  Shelf list sheet. (Reduced; actual size. 10 x 25 cm.)
Book No.  Accession No.  Vol.  Author Title
qG62 88390 Goodrich British eloquence
M11 540 2 Macauley Speeches
            820
W72 49408 Windham]

[Illustration:  Shelf-list card. (Reduced; actual size, 5 x 12-1/2 cm.)

090 Slater
S11 Book collecting
                      3528]

CHAPTER XXV

Cataloging books

After the books are accessioned, classified, author-numbered or book-marked, and shelf-listed, they should be cataloged.  A catalog is a labor-saving device in library work.  From it both reader and attendant can ascertain whether the library has a certain book.  By consulting the catalog for the class-number, the book may be looked for in its proper place, thus often saving hunting through the shelves in several classes.