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Using Call Numbers

Classification Systems and Call Numbers

The call number determines the location on the shelf of a book, government document, or microform in the Colgate Libraries.  Call numbers are also used to locate journals in the Cooley Science Library. Call numbers are created according to a classification system. Such systems divide "all knowledge" into broad categories or classes, and assign a number or letter to each class. Further subclasses eventually result in a call number which uniquely identifies a book and assigns it a place on the shelves. It is not necessary to understand the knowledge classification represented in a call number when one is trying to find a book on the shelf. The following information will assist in translating call numbers into actual shelf locations.

The Colgate Libraries currently use three different types of call number: Dewey Decimal, Library of Congress, and Superintendent of Documents.

Library of Congress call numbers

Materials with L.C. call numbers are arranged by subject on the shelves:

• alphabetically by class letter or letters (A-Z)
• then numerically within the class

By convention, "nothing always comes before something", so an H will come before HB.

L.C. call numbers commonly have decimal points.  These may appear in any line which has numbers. Numbers before the decimal point are read as whole numbers; numbers appearing anywhere after the decimal point are read as decimals.

These are in correct order:

Dewey Decimal call numbers

Books with Dewey call numbers are arranged by subject on the shelves:

• numerically by the class number (000-999)
• then alphanumerically by the second part of the call number

Again, "nothing comes before something" -- B75 comes before B75c.

Dewey call numbers also use decimal points. Any number which comes after the first three digits (the class number) is read as a decimal, regardless of whether or not there is a decimal point present.

These are in correct order:

Superintendent of Documents call numbers

Materials with SuDocs call numbers are arranged by government agency on the shelves:

• alphanumerically by call number stem (class letters and numbers preceding the colon)
• then alphanumerically the second part of the call number (following the colon)

There are 3 basic rules to finding a SuDocs number:

1. Again, "nothing comes before something" -- Y 4.SE 2:  comes before Y 4.SE 2/1:
2. Letters come before numbers -- Y 4.SE 2:H 36/18 comes before Y 4.SE 2:101-1-2
3. SuDocs numbers differ from Dewey and L.C. call numbers in that they do not use decimal points (they use periods, instead), so that all numbers in a SuDocs call number are whole numbers; there are no decimals -- S 1.10: comes before S 1.142/2:

These are in correct order:

dhughes@mail.colgate.edu 08/17/07
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