On 8/28/07, Roy Tennant <[log in to unmask]> wrote:
> the files at <http://www.loc.gov/catdir/cpso/lcco/>

The files Roy mentions are a great start, and might be enough for your purposes.

But they don't go into the full gory detail of the classification.
For example, if you are interested in QA934, you can only get as close
as:
    "QA801-939  Analytic mechanics"

If you do need the full, detailed classification, LC's "Classification
Web" appears to be based on a set of MARC records.  Here's an example
for QA934:

--------------------
ID: CF 94037268    Rec Stat: n    Entrd: 930427    Used: 19960528
CNID: DLC    Rec Type: w    KOR: a    NumType: a    Val: a
Opt: a    Enc Levl: n    Syn: a    Dis: a

010                                     $a CF 94037268
040                                     $a DLC $c DLC
084             0                       $a lcc
153                                     $a QA934 $h Mathematics $h Analytic mechanics $h
Elasticity. Plasticity $j Torsion
753                                     $a Torsion $b Analytic mechanics

Record:         85693
Added:          Tue Apr 27 00:00:00 1993
Modified:       Tue May 28 10:09:38 1996
--------------------

The drawback is that these records only appear to be available through
the subscription-accessed "Classification Web".  I couldn't find any
mention of the availability of the actual MARC records on the
Cataloging Distribution Service website.

Maybe LC will make them available via a free RESTful web service... :)

-Keith