J. Juvenile.
K. Miscellaneous and magazines.
As an illustration of the way a book is marked in this scheme, B 2574 might be Green’s “History of the English people.” This book is marked B. because it is a history. It is marked 2574 because there were already 2573 books in this class at the time this book was added. This mark, B 2574, is a very simple one and to that extent satisfactory. The scheme is a great advance over the preceding one, because it brings the books of a kind together. Since there are ten classes in this scheme, it is evident that if a reader wishes to see all the books on one subject he will have to examine only one-tenth of the library instead of the whole of it, but even this is not felt to be minute enough. If the library contains 200,000 volumes one class would contain, on the average, 20,000 volumes, which is altogether too great a collection to search through. If Green’s “History of the English people” were marked B 2574, the next book might be Robinson’s “History of Peru,” marked B 2575, which is of course a very different subject. The case is still worse in class E, which includes fine arts, useful arts and all the sciences, so that a book on chemistry might stand between a book on medicine and one on Raphael. This would not satisfy the reading public of to-day,—nor the modern librarian. The classes F, fiction, and J, juvenile, are not so bad; there is not so great a difference between the books in these classes. They are used more by people seeking recreation, rather than by those looking for definite titles. Jacob Abbott wrote some two hundred juvenile books and many of these might be scattered among the large class J. In class F, fiction, the English, French, and German authors would all be thrown together. This would be a disadvantage for any one desiring to read along a particular line.
Open vs. Close Classification.—The question of open vs. close classification is an important one. By open classification we mean one without minute subdivisions. An illustration of open classification is the scheme of ten classes described above. As an extreme case of open classification mention may be made of the theological library in which only two classes were used, the one class containing the books that were sound in their theology, the other the books that were unsound.
At the present time the tendency is towards close classification. It is a necessity in large libraries and an advantage in small ones. In this country the two great authorities on classification are Charles A. Cutter and Melvil Dewey. Both have devised and published schemes of classification which are generally recognized as having many excellent features. In both schemes the classification admits of very minute subdivisions. Dewey says that if the library has only one book on a certain minute subject, that book ought to be put in its own special class. It does not matter if there is no other book in the class. No one can fully understand what is meant by close classification until he has had considerable experience in classifying books. You can pick up the printed scheme of classification and run your eye over the numbers, but you will get comparatively little from them until you try to apply them.
Minute Bibliographical Classification.—The following is a very important distinction in regard to close classification which should be carefully noted. It is one thing to classify books, but it is quite a different thing to classify articles in magazines for the bibliography of a subject. Magazine articles may be classified far more minutely than books can be. Take, for example, the Bibliographia Geologica, in which references are made to articles in geological magazines and publications of geological societies. Here the articles are classified according to Dewey. Dewey’s class 551 means physical geology. In this bibliography there is a particular article marked 551.795,513,111,044. That is to say the general subject of physical geology is subdivided in one-trillionth parts and this article is assigned to one of those parts. If one should apply for a library position and be told that he should have to classify the books as closely as this, he would probably never get the position. If he were given this article to classify, he would just as likely as not put it ten billion points out of the way. As a matter of fact, this bibliography is compiled by a number of experts in geology. There are similar bibliographies of botany, zoology and other natural sciences, all minutely classified and all compiled by experts.
The reason that books cannot be as closely classified as magazine articles is that they generally deal with broader topics. In the average library it does not pay to classify books more minutely than is warranted by the general run of books in the class in which these books are to be assigned. In this regard, a distinction must be made between libraries. The Library of Congress has devised a classification of its own which is very minute, and a number of classifiers are employed to look after the different fields in which they are more or less expert. In this way, classification can be carried to the extreme limit of closeness. Nothing keeps one more modest than classifying, for one is continually brought face to face with things that one does not know, and so many things of which one knows so little.
The Dewey Decimal Classification. The decimal classification is used in this country and in Europe. It is suitable for both large and small collections of books and for indexing. In many schemes of classification letters are used to denote the classes, in others a combination of letters and figures. Dewey uses only figures.
Dewey developed his system in 1873 and published it in 1876. Numbers of three figures were used to denote the classes. Since then it has been found desirable to subdivide much more minutely and this has been done with increasing minuteness in the seven editions that have followed the one of 1876. A general outline of Dewey is here given.
000 General works