Library of Congress Classification
(Part 1)
April 20, 2005
1
Overview
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2
History
Characteristics
System Structure
Notational Structure
Double Cutters
Tables
Demo of Classification Plus
History
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LC Classification schedules developed 18981910
Emphasized LC’s collection strengths: social
sciences (political science, law, history)
Originally, little emphasis on humanities,
religion & philosophy
History (cont.)
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In early years, schedules revised periodically
Today, schedules are revised continuously (see
Weekly Lists)
Some schedules only recently published:
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KBR, history of canon law, 2001
KBU, law of the Roman Catholic Church, 2001
KBM, Jewish law, 2002
KBP, Islamic law, 2002
Characteristics
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Enumerative - every topic explicitly listed
No synthetic features
3½ shelf feet long!
Characteristics (cont.)
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Nonexpressive: notation does not reflect
hierarchical relationships
Example:
QH501-531
Life
QH540-549.5 Ecology
QH573-671
Cytology
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Hospitality
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Very hospitable: capacity to accommodate changes is
very great
Gaps in lettering and numbering can be used for new
topics
Decimal numbers can be added
Examples:
Subclass ZA (information resources) added to Z class in 1996
N6502.57.V53
Video art
added April 13, 2005
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http://www.loc.gov/catdir/cpso/wlc05/awlc0515.pdf
System Structure
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21 classes using letters
A
B
C
…
U
V
General works
Philosophy. Religion
History: Auxiliary sciences
Z
Bibliography. Library science. Info resources
Military science
Naval science
System Structure (cont.)
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Subclasses usually designated by a second
letter (exceptionally by a third)
Q
Science (general)
QA Mathematics
QB
Astronomy
QC
Physics
System Structure (cont.)
7 categories provide structure within each
schedule as well as within subcategories
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Physical format
Philosophy
Study and teaching
General works
Laws and regulations
Juvenile works
Topical subdivisions
Notational structure
Alphabetic subclasses are further divided by
sequential cardinal numbers from 1 to 9999
Example:
QC 1-75
Physics in general
QC 81-114
Weights and measures
QC 120-168.85
Descriptive and
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experimental mechanics
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Notational structure (cont.)
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Decimal numbers are sometimes used when
topics are added
Example:
QC 814
QC 815
QC 815.2
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Early works through 1800
General works, treatises, and textbooks
1801-1969
1970-
Cutter Numbers in Classification
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Cutter numbers developed for shelflisting
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Arranges all works in a class by main entry (author
or title)
In LCCS, cutter numbers are sometimes used
to subdivide classes
Cutter Numbers in Classification
(cont.)
Examples:
Geomagnetism
QC 811-QC 849
Observatories
QC 818.A2
General works
QC 818.A5-Z
By region or country, A-Z
A work on geomagnetism observatories in
Canada would be classed in QC818.C2
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Cutter Numbers in Classification
(cont.)
This results in two cutter numbers:
1.
2.
Subclass division
Cutter for main entry
Example:
The geomagnetism observatories of Canada / by I.M.
Lodestone.
QC818.C2 $b L64 2005
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Cutter Numbers in Classification
(cont.)
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Except in Class G, no more than two cutter
numbers are allowed
In some cases, two cutter numbers are used in
the classification tables.
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The 1st cutter is for a topical subclass
The 2nd cutter is for a geographic country or locality
or name of a corporate body, etc.
A digit is added to the second cutter for the main
entry
Cutter Numbers in Classification
(cont.)
Example:
Propaganda and censorship during Canada’s great
war / by Jeff Keshen, 1996.
D639
class number for World War I
.P7
subclass for propaganda
C24
sub-subclass for Canada; added digit
for Keshen
1996
year of publication
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Tables in LCCS
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Recurring patterns of subdivisions appear in
tables
References to tables appear in the schedules
Tables may contain:
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cutter numbers to be added to a base class, or
Arabic numbers to be added to a base number
In-class exercise: classifying
beavers
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Classify the following
topics:
Mammals of the world
Mammals of the Czech
Republic
Beaver reproduction
Rodent reproduction
Ecology of beavers
Aquatic mammals of
Central Europe
Fossil beavers