lib-s-mocs-kmc364-20141005045237


223 

Cumulating the Supplements to the 
Seventh Edition of LC Subject Headings 

Roy B. TORKINGTON: Central Library and Documentation Branch, In-
ternational Labour Office. 0 At the time of writing, the author was head, 
Library Systems Department, University of California, San Diego. 

A description is presented of the project of the University of California 
Library Automation Program to cumulate the 1966 through 1971 supple-
ments to the Library of Congress Subject Headings. The University 
of California Institute of Library Research MARC processing soft-
ware, BIBCON, was used, with specially written programs. The resulting 
cumulation was edited, printed in book form, and made available to li-
braries. The final task involved merging six MARC files into one file of 
over 125,000 records and then printing that file in a format similar to that 
of LC Subject Headings. The project was a cooperative effort with partici-
pation by people from several UC campuses. 

INTRODUCTION 

The seventh edition of Subject Headings Used in the Dictionary Catalogs 
of the Library of Congress was published with a cutoff date of June 30, 
1964. The first supplement covered additions and changes from July 1, 
1964 through December 31, 1965. Subsequent supplements were issued an-
nually, with each annual cumulating quarterly over a one-year period.1• 2 

By 1972, when the supplement for 1971 was issued, it was necessary, when 
assigning or verifying subject headings, to use seven supplements ( 1964/ 
65, 1966, 1967, 1968, 1969, 1970, 1971) in addition to the seventh edition. 
The Supplement Cumulation Task of the University of California Li-
brary Automation Program aimed at alleviating that problem by merging 
the 1966 through 1971 annual supplements into one cumulation. Through 
the courtesy of the Library of Congress we were able to obtain unedited 
magnetic tape files of all supplements except the 1964/65; these files were 
in the LC internal format. 

The University of California Library Automation Program undertakes 
cooperative automation programs which will benefit UC libraries. The cu-

0 The views expressed in this document may not be considered those of the Inter-
national Labour Office. 



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Cumulating Supplements to LC Subject HeadingsjTORKlNGTON 225 

mulative supplement task was seen as a low-cost project which could result 
in a product useful to UC and other libraries. We intended to use soft-
ware already available at UC as much as possible. The available software 
was BIBCON, a group of MARC processing programs developed and used 
by the UC Institute of Library Research, Berkeley, and UC Santa Cruz, 
for production of the 1963-1967 UC Union Catalog Supplement and the 
UC Santa Cruz book catalog.8 The BIBCON programs to be used were: 
SKED, a sort key creator and editor; BIBLIST and BIBPRINT, record, 
column, and page formatters; and FIX, a record corrector. Essentially we 
considered the problem of cumulating the supplements as one of produc-
ing a book catalog by cumulating several annual catalogs. Thus we needed 
a program to convert the LC internal format to UC MARC (SUPCON) 
and a merge program ( SUPMRG) (see Figures 1 and 2) . 

MERGE TRANSACTIONS 

A special merge program was necessary, because merging the supplement 
files is more complex than merely interfiling entries. Frequent matches or 
<nits" modify each other. In fact, the merge logic was critical to the whole 
process and dictated the design of the record format. Assume that we have 
the following sequence of headings given in the seventh edition of Sub-
feet Headings and modified as shown by the 1966, 1968, and 1970 annuals 
supplements. (The word «Number" refers to classification numbers asso-
ciated with the headings. ) 

Seventh Edition 

1966 Supplement 

1968 Supplement 

1970 Supplement 

Heading (Old Number) 
xx TracingD 

Heading 
xx TracingA 

TracingC 

Heading (Direct) (New Number) 
CANCEL 
Heading (Old Number) 

xxTracingB 
CANCEL 

xxTracing C 

CANCEL 
Heading (Direct) (New N urn ber) 
CANCEL 

xxTracingA 
CANCEL 

xxTracingB 
CANCEL 

xx TracingD 



226 Journal of Library Automation Vol. 6/4 December 1973 

We planned the merge to take place annual by annual, beginning by 
merging the 1967 supplement into the 1966, producing a 1966-67 cumula-
tion. The 1968 supplement was then merged into the 1966-67 cumulation 
and so on, proceeding until all available files were cumulated. With the 
example given above, the following steps would be used to produce the 
final cumulation: ' 

1966--67 Cumulation 

1966-68 Cumulation 

1966-69 Cumulation 

1966~ 70 Cumulation 

No change from 1966 annual 

Heading (Direct) (New Number) 
CANCEL 
Heading (Old Number) 

xx TracingA 
TracingB 

No change from 1966-68 

CANCEL 
Heading (Old Number) 
CANCEL 

xxTracingD 

After the final cumulation we see that the heading and its class number 
and tracing have all been canceled. A user checking both the seventh edi-
tion of Subfect Headings and the cumulated supplement would see that the 
heading and its tracing had been canceled and would not use it. 

The examples given demonstrate many of the transactions which occur 
in cumulating the supplement. Class numbers and tracings are added and 
deleted, direct/indirect status is changed, headings are canceled. Other 
transactions involve adding new headings and subdivisions, reinstating pre-
viously canceled headings, and canceling headings added in previous sup-
plements. In merging supplements into an old master file (i.e., producing 
an eighth edition), one would delete from the file a canceled heading or 
tracing. However, when cumulating a supplement one must differentiate 
between a cancellation and a deletion. Thus, in the example, the 1968 sup-
plement canceled Tracing C. Since Tracing C was added by the 1966 sup-
plement, the net result for the cumulation is to delete Tracing C (i.e., re-
move it from the file). In the 1970 supplement, Tracing D is also canceled. 
Since this tracing was added by the seventh edition the cancel information 
for it must remain in the file. A cancel transaction in a supplement ca n 
thus result in either deleting d ata from the cumulated file or adding data. 
If the original data first appeared in the seventh edition and is later can-
celed, the cancel record remains in the cumulated supplement. If the orig-
inal data first appeared in a supplement and is canceled in a later supple-
ment, the record is deleted, i.e., removed from the cumulative supplement. 
If the cumulative supplement were to be merged into the seventh edition 
file, all cancels would be deletes. 



Cumulating Supplements to LC Sub;ect Headings j TORKINGTON 227 

RECORD FORMAT 

At first we gave serious consideration to defining the record so that one 
heading (or heading and its subdivisions) and all its references and trac-
ings occurred as separate fields and/ or subfields in one MARC-structured 
record. This creates a serious problem in the merge when adding and delet-
ing references and tracings. Each of the transactions shown in the example 
would require adding data to, or removing data from, the variable fields 
of a MARC record. We decided to simplify the record structure along the 
lines of LC's internal format and thus simplify the merge program:' 

Since any heading, subdivision, reference, tracing, note, or class number 
in a supplement can be added, canceled, or deleted, the format is defined 
so that every one of those elements would establish a record. Direct/Indi-
rect information is carried in the heading or subdivision record as one 
character in the fixed field. Also, each record for a subdivision, class num-
ber, reference, tracing, or note contains the headings and subdivisions un-
der which it files. Each element occurs as a variable field in the MARC rec-
ord. Consider the following example from the 1967 supplement: 

Building materials 
sa Structural engineering 
-Research (Direct) (TA404.2) 

xx Materials research 

This is represented by five MARC records with variable fields tagged as 
shown in the following example. (Examples are only representations of 
MARC records. Tags actually occur in the directory. Indicators and delim-
iters associated with variable fields are not shown. ) 

Record 1: 150 Building Materials 
Record 2: 150 Building Materials 

710 Structural Engineering 
Record 3: 150 Building Materials 

201 Research 
(Direct Indicated in Fixed Fields ) 

Record 4: 150 Building Materials 
201 Research 
050 ( T A404.2) 

Record 5: 150 Building Materials 
201 Research 
711 Materials Research 

Cases in the printed supplements where a heading is canceled and then 
reestablished in order to change class number or Direct/ Indirect indica~ 
tion required special d efinition. Thus : 

Heading (Direct) (Number) 
CANCEL 



228 Journal of Library Automation Vol. 6/ 4 December 1973 

Became one record: 

Also: 

Became three records: 

Heading (Number) 
l50Heading 
(Direct Indicated in Fixed Fields) 
Heading (New Number) 
CANCEL 
Heading (Old Number) 
150 Heading 

150Heading 
050 (New Number) 

!50 Heading 
050 (Old Number) 
(Cancel Indicated in Leader) 

Table 1. UC MARC Subject Supplement Variable Fields 
001 LC locator number 
008 Fixed fields 
045 Special sorting field 
050 LC classification number 
150 Heading 
201 Subdivision 1 
202 Subdivision 2 
203 Subdivision 3 
204 Subdivision 4 
500 Scope Note 
501 Example or note under 
510 General see note 
520 General sa note 
700 See reference 
701 x tracing 
710 sa reference 
711 xx tracing 
790 First See reference ~ Temporary tags set 
791 First x tracing and used only by 
792 First sa reference SUPPER and BIBLIST 
793 First xx tracing programs 
999 Special tag reserved for SKED and BIBLIST programs 

MERGE LOGIC 
The UC SKED program can generate 256-byte sort keys that will cause 

each record to sort in the desired sequence. Because of program and fund 
limitations, certain types of filing were ignored, e.g., chronological, geo-
graphic, diacritics, and some hyphenated headings. For acronyms, initial-
isms, and some abbreviations, we inserted special filing fields as part of the 
postmerge edit process. Generally, however, we were able to come quite 
close to LC Subject Headings filing by strictly programmatic means. Since 
the merge program logic requires records in sequential order by key, it was 
necessary to sort the files after adding keys to them, to correct for the dif~ 
ference between key order and LC Subject Headings filing. 

The greatest variation from LC Subject Headings filing practice occurs 
in our treatment of chronological and geographic subdivision. Instead of 
filing in chronological order: 



Cumulating Supplements to LC Subiect Headings/ TORKINGTON 229 

u.s. 
-History 
-Revolution 
-1783-1865 
-Civil War 

we file in alphabetical order: 

u.s. 
U.S.-History 
U.S.-History-1783-1865 
U.S.-History-Civil War 
U.S.-History-Revolution 

Surprisingly, there have been very few complaints from librarians about 
this filing method. It does not appear to have impaired the utility of the 
cumulation. 

The merge program ( SUPMRG) is shown in Figure 3. Annuals are 
merged into previous cumulations until an annual record ( ANNREC) and 
a cumulation record (CUMREC) have equal keys (AKEY=CKEY). For 
records with very long fields, usually scope notes, the key may require more 
than 256 characters. In these cases it is truncated. In only one case out of 
a series of merges involving over 100,000 records were truncated keys 
matched. 

As can be seen from Figure 3, the record format makes it possible for 
SUPMRG to merge the files without modifying any variable fields. 
SUPMRG, as a result, does not require modules for rebuilding and modi-
fying MARC records. 

Figure 3 shows that a match of reference, tracing, etc., records is error 
free only when one record is a cancel and the other is not. Otherwise the 
system is attempting to duplicate an add or a cancel. However, i~ the case 
of headings and subdivisions it is possible, and indeed common, to have 
matches of records which are not cancels. This occurs whenever new trac-
ings or references are added to a heading or subdivision already in the 
cumulated file. In our first example the first records from the 1966 supple-
ment will bt· · 150 Heading. From the 1968 supplement: 

150Heading 
(Direct Indicated in Fixed Fields) 

SUPMRG sets the Direct/ Indirect indicator, writes a record to output, and 
continues merging. An add-cancel match with references and tracings re-
sults in no record in the cumulation (e.g., Tracing C in the same example); 
the two records delete each other. In the case of headings and subdivisions, 
however, we cannot be certain that a canceled heading was added in a 
supplement and is not in the seventh edition. Hence, headings and sub-
divisions are never deleted. This leaves a few ghosts which should be de-
leted, i.e. canceled headings which were added in supplements and later 



230 Journal of Library Automation Vol. 6/ 4 December 1973 

Fig. 3. Supplement merge program (SUPMRG). 

Write 
CIJMREC to 

Output 

canceled. The problem was judged to be unavoidable and relatively harm-
less. 

PRINT FORMAT 

Example 1 shows a sample of printed output from the cumulation. It 
varies from the printed format of LC Subject Headings as shown in Ex-

-



Cumulating Supplements to LC Subject Headings/ TORKINGTON 231 

Set Direct/ 
Indirect 
IDdkator 

Write 
CUMI\ECto 

Cltltput 

Fig. 3 (continued) 

No 

Set Direct/ 
Indirect 

Indira tor 

Print 
Reinstatement 

Message 

Write 
ANNI\EC 
to Otltpu t 

Set Direct/ \\trite 
lndltect CUMREC 
lndlcat.or fo Ontput 

W rite 
0 

ANNREC to 
Output 

ample 2. In the cumulation, headings and subdivisions are r epeated, only 
one type font is used, and diacritics are ignored both in printing and fil~ 
in g. Also, placement of (Direct ), (Indirect) and class numbers differs 
from the LC style. 

The cumulation was formatted and printed using three programs: 
SUPPER, BIBLIST, and BIBPRINT. BIBLIST and BIBPRINT are part 
of the Institute of Library Research ( ILR) BIBCON software package 
and were designed for printing book catalogs. SUPPER was written spe· 
cially for the supplement cumulation to prepare records for BIBLIST; it 
places records containing variable fields for ( Direct), (Indirect), and 



232 ]ourool of Library Automation Vol 6/ 4 December 1973 

Botany, Economic 
(Indirect) 

CANCEL 
Works on the economic botany of 

individual localities are entered under 
1. Botany, EconoMic. 2. Botany·- local 
subdivision 

sa Fiber plants 
Fungi--Economic aspects 

CANCEL 
sa Textile fibers 

Botany, Expe~lmental 
x Experimental botany 

Botany, Medical 
Botany, Medical--Pictori&l works 
Botflies 

sa Sheep botfly 
Botswana 
Botswana--History 
Botsvana--History--1966-
Botswana--History--To 1966 
Bottle qardens 

See Glass gardens 
Bottle tickets 

See Wine labels 
Bottlenosed dolphins 

(QL737. cq) 
xx Dolphins 

Bottles 
(Direct) 

(Art, NK5440: Technology, TP866) 
CllfC!L 

(TP866) 
sa Bitters bottles 

Miniature bottles 
Poison bottles 

x Flasks 
xx Glassware 

BottloA••Collectors and collecting 
(Direct) 

Bottles--Collectors and collectinq-·Caricatures 
and cartoons 

Example 1 



Cumulating Supplements to LC Subject Headingsj TORKINGTON 233 

Boenia and Herze~eonna t 
-History t 

-1878-1918 
-1918· 

Boeton Tea Party, 1773 t 
-Juvenile literature 

Botany t 
-Clauifteation t 

Ill Planta-ldentlfteation • 
-Ecology t 

111 Island flora 
-Experiments 
-Identification • 

See Planta-ldentifteation 
-Variation t 

Ill Island flora 

Botany, Economic t 
1t1 Fungi- Eeonomle upeeb 

Botawana • 
-History 

-To 1966 
-1966-

Bottle tickets • 
See Wine labels 

Bottles (Direct) (Art, NKI.t-'tJ; 
Technologv, TPB86) t 

CANCEL: 
Bottles (TP866) t 

~:r Glassware 

Bottles, American, [etc.) 
z American [etc.) bottlea 

Bottom relief, Ocean 
See Submarine topographY. 

Boulou language • 
See Bulu language 

Boundary layer control t 
1e1 Vortex generators • 

Boxln~t accident! 
See Boxing- Accidents and lnjuriea 

Bora t 
1a Fathers and aona • 

Mothers and aona • 
-Prayer-books and devotionl 

(BV2B$.81) t 
CANCEL: 

-Prayer-books and devotions t 
CANCEL: 

8ubcltvlded by lan~tual(t!. 
:t Boys-Prayer-books and 

devotions- English 
-English 

See Boys-Prayer·booka and 
devotions 

-French, [German,Ualian. ete.) 

Braid t 
14 Braiding machinery 

Braiding machinery (TS1'111.1) 
zz Braid 

Textile machinery 

BraJn t 
1a Corpus callosum 

Globus pallidua 
Subthalamus 

-Abnormities and deformitiea t 
CANCEL: 

E:r:ample under Deformitie• 
-Blood-veasela t 

-Surgery 
-Diseases t 

14 Cerebral edema 
-Edema 

See Cerebral edema 
-Electromechanical analogle1 

:~:z Brain-Models 
-Models t 

1a Brain- Eleetromeebanleal 
analogie1 

-Reaearch 
See Brain research 

-surgery t 
111 Frontal lobotomy 

Example 2 

CANCEL in appropriate places in the merged file, and also strips keys 
from records. 

SKED and BIBLIST were originally designed to interface in producing 
book catalogs. In processing a MARC bibliographic master record, one 
wishes to explode the master record so that there is a keyed record for 
every subject heading and added entry. The records are then sorted on key 



234 Journal of Library Automation Vol. 6/ 4 December 1973 

and printed. With bibliographic data the first element of the key will be 
the first element printed. Title records are filed on title, and the title is the 
first printed element of a title entry; similarly, with name and subject eJ?.-
tries. The key itself is so edited by SKED (all uppercase, no punctuation, 
super blanks added) as to be useless for printing. As a result, sorted records 
coming into BIBLIST must have an indication of the tag which generated 
the first element of the key. This is accomplished by use of a 999 tag in the 
MARC record directory which contains the tag and sequence number of 
the appropriate field. SKED adds the 999 tag to the record and BIBLIST 
uses it to format print records. 

The problem with using this interface in printing the cumulated sup-
plements is that all keys begin with the 150 (i.e., heading) field, whereas 
print lines for tracings, references, etc., do not. The solution was to have 
SKED add the 999 tags, and have SUPPER modify them so that they point 
to the tags for the fields which are to be printed. 

Another problem with BIBLIST occurred when a series of, say, xx trac-
ings occurred under a heading. We wanted to follow LC Subject Headings 
format and print an "xx" preceding only the first "see also from" !:facing in 
the column. BIBLIST cannot distinguish between the first record contain-
ing a 711 variable field (i.e., xx tracing) and following records with 711 
fields. Either all would have xx printed or none would. To solve this prob-
lem we set up a special set of tag values for first x, and xx tracings, and 
first See and sa references. These values were used only by the print pro-
gram. SUPPER changed the appropriate directory entries, and BIBLIST 
used them in formatting lines. 

Obviously BIBLIST could have been modified to do all this processing. 
However, we judged it easier and quicker to write a relatively simple key 
stripper and tag changer (i.e., SUPPER) than to modify a complex, table-
driven program such as BIBLIST. 

COORDINATION 

The UC Library Automation Program (LAP) is a cooperative effort in-
volving representatives from all nine UC campuses and a central program 
office. The people working on the cumulation were scattered from San 
Diego to Berkeley. Three different IBM 360 computers were used, two of 
them under the OS, one under the DOS operating system. 

This decentralization was not the result of poor planning, but was done 
deliberately. The cumulation project was a minor task of LAP and there 
was not staff available at any one location to work on it. The only solution 
was to farm tasks out to available people, of whom there were few. Since 
the project manager was at San Diego and did not have access to an IBM 
360 running under OS, his programs ( SUPCON, SUPMRG, SUPPER, 
SUPUNK) were written to run on an available DOS system. Eventually, 
if LC does not cumulate supplements to the eighth edition of Subject 
Headings, the programs will be converted to run under OS. No program-



Cumulating Supplements to LC Subject HeadingsjTORKINGTON 235 

mer has been available to do this yet. Likewise, it was impossible to install 
the BIBCON programs at San Diego, since they ran under OS. Hence 
SKED, BIBLIST, and BIBPRINT were set up and run elsewhere. 

Initially, this project was conceived as part of a test of cooperative de-
velopment. In this case, cooperation was successful. However, a task of 
systems development in line operations, such as acquisitions or circulation, 
involving large scale changes in library procedures, might not be successful 
under such conditions. This project was a relatively small but iJ.iteresting 
task which did not involve changes in library operations. 

Running on more than one computer and under two different operating 
systems caused problems. Tapes were continually sent by intercampus bus 
between Santa Barbara and San Diego, a distance of 200 miles. The prob-
lem was compounded when multireel files were involved and we wished to 
label them. Unfortunately, IBM 360 DOS tape labels and IBM 360 OS 
tape labels are mutually incompatible-a noteworthy nuisance. Program 
testing was also difficult. Frequently, the best test of a program is to run its 
output through the next program in the system. When the next program 
is 200 miles away and a tape must be mailed, delays become routine. 

CUMULATION SYSTEM 

Figures 1 and 2 depict the cumulation system. Figure 1 shows the steps 
involved in producing a preliminary 1966-70 cumulation. This cumula-
tion was edited by part-time student assistants using procedures developed 
by a librarian working on the project. Corrections were made by the 
BIBCON program FIX, and the corrected cumulation was rekeyed and 
sorted. Figure 2 shows the annual cycle. We began this cycle with the 1971 
supplement and the edited 1966-70 cumulation. A new cumulation (in this 
case, 1966-71) was printed. The new cumulation is retained with sort keys 
and becomes next year's old cumulation, obviating the necessity of rekey-
ing and resorting this large file (over 125,000 records). 

COSTS 

The cost of the project was less than six thousand dollars, including sal-
ary costs of editors and keypunchers, but not of the project manager at 
UCSD and the programmer at UCSB who worked on this project along 
with several others, contributing varying amounts of time. The cost in-
cludes the cost of all computer runs, from testing and debugging through 
production. Printshop costs are excluded. However, the cost of computer 
runs to print out reproducible copy for both the 1966-70 and 1966- 71 
cumulations is included. The cost of one annual cycle (excluding print-
shop and labor costs) is about five hundred dollars. It should be noted that 
the cost of a quarter-time analyst and programmer will easily double these 
costs. 



236 Journal of Library Automation Vol. 6/ 4 December 1973 

CONCLUSION 

The cumulation was well received by librarians; copies have been sold, 
to non-UC libraries, grossing more than enough to repay the cost of -the 
project. Future plans are extremely dependent upon LC's cumulation pat-
tern after the eighth edition of Subject Headings. If LC cumulates its 
supplements annually or if it brings out new editions at frequent inter-
vals, say, every three years, there will be no more need for the UC Cumula-
tion and it will be discontinued. 

REFERENCES 

1. U.S. Library of Congress. Subject Cataloging Division, Subject Headings Used in 
the Dictionary Catalogs of the Library of Congress (7th ed., Washington: Library 
of Congress, 1966) and its Supplements. 

2. Robert R. Holmes, "Introduction to the Seventh Edition of Subject Headings Used 
in the Dictionary Catalogs of the Library of Congress," Library Resources and 
Technical Services 12:323-29 (Summer 1968). 

3. Liz Gibson, "BIBCON; A General-Purpose Software System for MARC-Based 
Book Catalog Production," Journal of Library Automation 6:237-56 (December, 1973). 

4. Henriette D. Avram, Lenore S. Maruyama, and John C. Rather, "Automation Activi-
ties in the Processing Department of the Library of Congress," Library Resources 
and Teclmical Seroices 16:195-239 (Spring 1972).