Excerpt from Decimal Classification and Relativ Index for Libraries, Clippings, Notes, Etc The field of knowledge is divided into nine main classes and these are numbered by the digits, 1 to 9. Cyclopedias, periodicals, etc., so general in character as to belong to no one of these classes are marked nought, and form a tenth class. Each class is similarly separated into 9 divisions, general works belonging to no division having nought in place of the division number. Divisions are similarly divided into 9 sections and the process is repeated as often as necessary. Thus 512 means Class 5 (natural Science), Division 1 (mathematics), Section 2 (algebra), and every Algebra is numbered 512. The books on the shelves and the cards in the subject catalog are arranged in simple numerical order, all class numbers being decimals. Since each subject has a definite number, it follows that all books on any subject must stand together. These tables show the order in which subjects follow one another. Thus 512 Algebra precedes 513 Geometry and follows 511 Arithmetic. Summaries. The first summary shows the ten Classes into which all topics are divided. The second summary shows the nine Divisions of each of the ten classes, and is useful as a bird's-eye view of the whole scheme on a single page. Then follow ten pages, one for each class, showing the nine Sections into which each of the nine divisions of each class are divided. These pages are to be used for a synoptic view on a single page of the scope of each class. Sub-sections. Following these three summaries is the complete classification, which repeats, in proper order, all the classes, divisions, and sections with all the sub-sections given under each section. Synonymous terms, examples, brief notes, dates, and various catch-words are often added to the simple heads for the convenience of the user, who thus gets a fuller and clearer idea of the field which each number covers. Therefore all references to numbers should be looked up in the full tables of sub-sections; never in the Summaries, which are really only a table of contents of the Complete Tables. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.