Reference books and the circulating collection at Jennings Library are classified using the Library of Congress system of call numbers.
About Call Numbers:
A uniqu identification number
Each book (or other item) has its own unique call number which is taped to the lower outside edge of the book’s spine.
A miniature subject formula
Books written about the same subject have similar call numbers, which groups them together on the shelf, making it easier for you to browse the library’s holdings on a specific topic.
A location code
A book’s call number also appears in the entry in CALCAT, the online catalog which lists the holdings of Jennings Library. Once you have located the entry for a specific book in CALCAT, make a note of its call number and then look for the book in call number order on the library shelves (also called the “stacks”). Location codes tell you where in the library the books will be found, i.e. Reference Department, Circulating Stacks, etc.
TWO KINDS OF CALL NUMBERS
Dewey Decimal Call Numbers
Most school and public libraries use a system called Dewey Decimal (DDC) call numbers which begin with Arabic numerals. In Jennings Library, Dewey Decimal call numbers are used for children’s picture books as well as juvenile fiction and non-fiction and Curriculum materials.
Library of Congress Call Numbers
Most academic and research libraries use an entirely different system called Library of Congress (LC) call numbers, which begin with letters of the English alphabet. For example, the book with the title A history of modern Germany : 1871 to present has the call number:
In CALCAT, the call number in the example given above is listed on a single line , with spaces between the four parts:
DD 220 .O67 1991
In the LC system, the first letter of the call number indicates the general subject area. The second letter indicates the specific sub-section within the general subject category. In the example given above, the first D in the call number indicates that the book is a work of history . The second D indicates that it is a work of German history .
In the LC system, works of fiction are assigned call numbers in the same way as nonfiction. Most works of fiction can be found in the P s, the section for literature .
HOW ARE LC CALL NUMBERS SHELVED?
Library of Congress call numbers usually have four lines or elements:
The first line can be either a single or a double letter. If a book’s call number begins with a single letter which is the same as the first letter of a call number which begins with a double letter, then the book with the single letter is shelved first , or to the left, on the shelf. For example, in the section for the P s, the correct sequence would be P PA PB PC PD to PZ , followed by Q QA QB QC QD and so on.
The second line of an LC call number is always a whole number from 1 to 9999 . If the letters on the first line of the call number are the same, the book with the smaller number on the second line is shelved to the left of the book with the larger number. (Note that in the Dewey Decimal system, the largest number is 999.)
The third line of an LC call number is always a decimal point, followed by a letter and a number. Books are shelved alphabetically according to the letter to the right of the decimal point. For example, a book with .G on the third line of its call number would be shelved to the left of a book with .H . If two books have the same letter on the third line, then the book with the smaller decimal number is shelved to the left of the book with the larger number. For example, .G53 is shelved to the left of .G532 because .53 is a smaller decimal number than .532 .
The fourth line of an LC call number is always a year of publication or a volume number. An earlier edition of the same work is always shelved to the left of a later edition A lower volume number is shelved to the left of a higher volume number.