Generating Cutter numbers

Gerard Flanagan grflanagan at
Mon May 22 10:36:57 CEST 2006

Terry Reedy wrote:
> "Gerard Flanagan" <grflanagan at> wrote in message
> news:1148146441.412605.163750 at
> > I'm cataloging a small library and want to generate a unique id (called
> > a 'call number') for each book.  This id is composed of:
> >
> > * Dewey 3-digit Subject Classification Number
> > * Dewey Decimal  (always 0 for the minute)
> > * Cutter Number
> > * Copy number  (multiple copies or volumes)
> >
> > (That Celestial Emporium again...)
> >
> > I haven't researched it much but it seems the Cutter number is used to
> > distinguish between authors with the same name, and between different
> > books written by the same author - so you need last name, first name
> > and title.  But it may be as much art as science.
> I seems you are mixing pieces of two cataloging systems.  The link you gave
> was for creating Cutter numbers to represent subtopics of Library of
> Congress classes.  For instance, 'algorithms' is .A43.

I think 'Cuttering' is a general term for identifying any given book
within a subject area. Whether you use Dewey or Library of Congress
system of subject classification you still need to have a way of
identifying particuar books.

>From the link below:

[Examples of] LC (Library of Congress) call numbers:

LB 1631.S686 1994

QA 76.76.H94 C36 1997

The first part of those call numbers, i.e. before the final decimal
point, are the "filing numbers" as they are often called. They
indicate the general subject area and are of no interest to us at this
point for they are shared by all other books in this class. All
libraries using the system will all use the same "pre-decimal" filing
number. But ... there could still be a whole wallfull of books sharing
those numbers so we still have a problem.

The part of the call number that really made Cutter's system famous --
and a winner -- was the stuff after the (final) decimal point. Those
are the
cutter numbers -- and those are the numbers that guarantee not only
book's uniqueness, but also lead us straight to its location once we
are in the right general area of the library.

Cutter numbers are in a sense "relative". They are not assigned in
some kind of absolute way, as are the filing numbers that precede
the decimal point. Thus if a book is "about science" then its filing
number will begin with a Q in a more absolute or determinate sense
because Q is the Library of Congress Classification for books on
science. All books using the LC system will end up giving each book
the same filing number, but they are unlikely to end up giving it
exactly the same cutter because every library is different and will
have different books on its shelf. Cutters depend, relatively, on what
other books are located in the general area in which a given book is
to be placed in that particular library.

So when a book has to be cuttered, then the table that Cutter provided
for allocating numbers is used. However, the resulting numbers must
fit into the order established by already existing books in the
library. That's to say, it is the librarian's responsibility to check
to be sure that no other book in this class has the same cutter

(Before clicking on the link give yourself 10 geek-points if you can
complete the following sentence:

The first real library -- i.e. the first one known to have
systematically tried to solve the problems of maintaining a collection
by imposing a "logical order" on its objects was the
Great Library of Alexandria. The Great Library's first librarian was...


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