Melvil Dewey

“ Theoretically, the division of every subject into just nine heads is absurd. Practically, it is desirable that the classification be as minute as possible without the use of additional figures, and the decimal principle on which our scheme hinges allows nine divisions as readily as a less number. This principle has proved wholly satisfactory in practice though it appears to destroy proper co-ordination in some places. It has seemed best in our library to use uniformly three figures in the class number. ”

“ 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. ”

“ 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. ”

“ The great mass of the library consists of 2-decimeter books, the size numbers of which are omitted. Books from 21⁄2 to 31⁄2 decimeters in height have 3 prefixed to the book number, and are found on the bottom shelf of each range. The larger sizes are prefixed with 4, 5, &c., and are found on the special shelves provided, in order to avoid the great waste of space otherwise occasioned by the relative location. By this use of the size numbers a close economy of space is secured. ”

“ 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. ”

“ These books treating of no special class, but general in their character, are divided into Cyclopedias, Periodicals, etc. No difficulty is found in following the arithmetical law and omitting the initial zero, so these numbers are printed 31, 32, etc., instead of 031, 032, etc.
The selection and arrangement of the thousand headings of the classification cannot be explained in detail for want of space. In all the work, philosophical theory and accuracy have been made to yield to practical usefulness. ”

“ The impossibility of making a satisfactory classification of all knowledge as preserved in books, has been appreciated from the first, and nothing of the kind attempted. Theoretical harmony and exactness has been repeatedly sacrificed to the practical requirements of the library or to the convenience of the department in the college. As in every scheme, many minor subjects have been put under general heads to which they do not strictly belong. In some cases these headings have been printed in a distinctive type, e. ”

“ Noblemen and ecclesiastical dignitaries are entered under their family names, but sovereigns, princes, oriental writers, friars, persons canonized, and all other persons known only by their first name, are entered under this first name. ”