The representation of symbols in an
index
Hans H. Wellisch
A section from Wellisch's newly published guide, Indexing from A to Z, on the form, order, and place in which to
represent symbols in an index.
Symbols are tricky things: their number is unlimited,
be the graphic representation of the number one or of a
the same symbol may mean many different things, the
high frontal lax vowel (as in 'bit'), i.e., the letter I; it may
same thing may have many different symbols, they are not
represent the chemical element iodine or indicate electrical
easy to define, and they are difficult if not impossible to
current; or it may be a symbol for several other things—all
index—yet. indexed they must be if they appear in the text
depending on the context in which the symbol appears.
of a document. Only a little more than a decade ago, index-
The most
frequently
used graphic symbols are, of
ers were not overly much concerned with symbols. In his
course, numerals and letters, but their treatment in indexes
textbook on indexing, G. N. Knight still thought that 'It is
not easy to imagine circumstances in which a symbol may
is taken care of by long-standing rules of mathematics and
have to be used as the keyword of a heading', but allowed
problems, namely: in which form, or in what order, and
that a symbol 'might well come as the second word and so
where to represent them in an index.
affect the order where there are several headings with the
same keyword'.1 It was, of course, well known that mathe
matical, astronomical, chemical, and other scientific texts
filing, respectively. All other graphic symbols pose three
Form of representation
contained symbols that sometimes had to be indexed (and
All symbols have names or designations, otherwise it
Knight gave a few examples of these), but, even in those
would be impossible to talk or write about them, or to
types of text, symbols were generally not very numerous
explain what they stand for. The names are different
and could more or less easily be dealt with in an index.
depending on the field of application, but within one such
Little did anyone in the late 1970s foresee the proliferation
field any symbol can, in principle, have only one name: the
of symbols in the technical manuals for computer software
symbol O always means only the 15th letter of the English
which must now be indexed to guide users to the many
dozens of different symbols for commands, instructions,
alphabet, and no other; it signifies only zero, and no other
and applications, ranging from punctuation marks to icons.
istry and physics; only one blood type, and so on. (The dif
numeral; it means oxygen, and no other element in chem
ferent
names
for
an
oblique
stroke
in
writing
and
printing—solidus, shilling, virgule, fraction, stroke, bar—
What is a symbol?
are an unfortunate exception, rarely if ever found elsewhere
A symbol is something representing something other
in the various symbol nomenclatures.) Since users of a text
than itself by association, resemblance, or convention*. For
in which symbols are discussed qua symbols may be
the purposes of indexing, only graphic symbols, or
graphemes in linguistic terminology, need to be consid
expected to know their names within the given context, the
ered. Thus, a short vertical stroke, in and of itself, is not a
symbol is its name or designation, spelled out in full, fol
symbol; it becomes one when it is associated in some
lowed by the symbol itself in parentheses and by its loca
body's mind with another thing for which it may stand as a
tors, e.g.,
kind of shorthand expression. The short vertical stroke may
* This definition, from the American heritage dictionary of the
English language, avoids mentioning the term sign; the often con
troversial distinctions made in philosophy and linguistics between
sign and symbol are irrelevant for written communication.
easiest and most straightforward form of entry for any
infinity (°°) 37,42
Such an entry should, of course, be made only if the
symbol for infinity is discussed in the text, and not for the
concept of infinity which, if also dealt with in the same
text, should have a normal entry, with that for the symbol
as a subheading, e.g.,
From Indexing from A to Z. Copyright ©
1991
by Hans H.
Wellisch. Reprinted by permission of the H. W. Wilson Company,
New York. All rights reserved.
The Indexer Vol. 17 No. 4 October 1991
infinity 80, 84, 96
symbol (°°) 37, 42
239
THE REPRESENTATION OF SYMBOLS
This method fails, however, to do two things: it does
for an index of proof correction marks. This method, while
not help a user who remembers the shape of a symbol but
does not know or remember its name; and it is not helpful
easy to explain to users, will necessarily disperse related
for many software symbols, which either signify a phrase
all indexes. It is probably best to use it when the number of
(e.g.. an instruction to do something) or are icons whose
function cannot always easily be expressed by a succinct
heading. Consequently, there is a need to display the sym
bols themselves, which in turn raises the question of their
symbols, but so does alphabetical arrangement of entries in
symbols to be displayed is small, say, no more than a
dozen or so.
Classified order. All symbols referring to a particular
class are displayed together, further subarranged either
alphabetically or in an order readily recognized by users
arrangement.
familiar with the discipline or field, e.g., icons for editing,
drawing, coloring, etc., each group arranged by name or
Order of representation
instruction; another example would be symbols for the
The virtually infinite variety of shapes in which graphic
symbols may appear effectively precludes any order that
assures in and of itself that any uninitiated user would
automatically find a particular symbol within an array of
planets which, if only a few, may be subarranged alphabet
ically from Earth to Venus (which would be abhorrent to
astronomers) or, if all nine appear, in the order of their dis
tance from the Sun, that is,
differently shaped ones, the way we all know that the letter
M is somewhere in the middle of the Roman alphabet, more
3
Mercury
precisely between the letters L and N, and in no other place.
9
Venus
The same is true of any number written in Arabic numerals
in the decimal system. This is so because every literate
person has to learn these ordering systems by heart as a
child, and retains this knowledge throughout life. No such
universally known and recognized ordering system exists
for graphic symbols, yet users may want to find symbols in
indexes to texts dealing with astronomy, biology,
chemistry, geology, engineering, the military, linguistics,
genealogy, and heraldry, to name only a few fields that
employ symbols frequently, not to mention arbitrary
symbols sometimes invented ad hoc by authors for certain
concepts or purposes, as well as icons, the symbols used on
monitors to produce pictorial effects. Icons are discussed at
length in software manuals, and there are often several
dozens of them; but their shapes are more often than not
quite
arbitrary
and
their
meanings
are
not
always
immediately obvious, nor do they always have succinct
names or descriptions. For example, in a particular software
application, the image of a pencil in an icon is indeed
named 'pencil' and is used to draw lines, but the image of a
butterfly net is called a 'selection net' and is used to 'select
a non-rectangular drawing area for editing', something that
can only be learned from the printed manual and so is not
common knowledge.
It is therefore necessary to show symbols in an index in
their physical shapes, and three possible methods may be
used for this purpose, depending on the nature of the text
and the amount of symbols to be displayed:
Alphabetical order. Each symbol is first displayed in its
graphic form in a separate list, followed by its name or
description in alphabetical order, e.g.,
II
align 12
U1
brackets 17
C
close up 10
A
delete 9
240
© Earth
6
Mars
% Jupiter
h
Saturn
& . Uranus
\y Neptune
e
Pluto
Authorized list order. Symbols are listed in the order in
which they are found in authoritative sources, such as major
dictionaries or style manuals.
A small selection of symbols, mainly of interest in
computer contexts, is covered by two different ordering
sequences which are more or less familiar to many (but by
no means all) computer users.
One
is
the American
standard code for information interchange (7-bit ASCII)2,
whose acronym ASCII is pronounced 'askee'; it is virtually
identical with the international standard ISO 646.' The
system assigns a three-digit code to each numeral and letter,
as well as to a few dozen symbols, e.g., the numeral 0 is
048,9 is 057, A is 065 and i is 097, a dollar sign is 036, and
a comma is 044, and so on for a total of 256 codes. ASCII
codes
are
predominantly
employed
in
the
realm
of
microcomputers, and if a text deals only with symbols
covered by these codes it makes sense to list symbols in
ASCII order, because the prospective users of manuals and
guidebooks on microcomputer software can reasonably be
expected to be familiar with it. Thus, a sequence of entries
for commands occurring in a software manual, where
symbols are the only distinguishing elements in otherwise
homographic headings, may be arranged in ASCII order,
e.g..
The Indexer Vol. 17 No. 4 October 1991
THE REPRESENTATION OF SYMBOLS
out; for single symbols (that is, those not preceded or
allowed by a numeral or letters), the explication should be
enclosed in brackets.
Unmodified ASCII codes as commonly embedded in
word-processing software should, however, never be used
for the alphabetization of verbal index headings, because
this would play havoc with their proper sequence: e.g., a
term enclosed in quotation marks would precede all
numerically and alphabetically arranged terms, and all
upper-case letters would sort before lower-case letters.
Specialized indexing software provides modification of
ASCII, resulting in correct alphanumeric sorting.)
The other system for the arrangement of symbols used
in computer contexts is the Extended Binary Coded
Decimal Interchange Code, fondly known as EBCDIC,
preferred by IBM for texts dealing with mainframe
computer software. Symbols in indexes to such texts may
therefore be arranged in that order. Since the curse of Babel
has struck also man-made computer languages and their
appurtenant ordering systems, there is no compatibility
between ASCII and EBCDIC, nor do they list the same set
of symbols. Neither ASCII nor EBCDIC cover icons.
Whichever system is used to arrange graphic symbols in
an index, an introductory note must make it clear which one
has been chosen, and a double entry in the verbal part of the
index, followed by the image of the symbol, should always
be made, e.g.,
9 Venus 48, 62
and
Venus ( 9 ) 48, 62
If none of the three ordering methods is suitable,
symbols must be arranged arbitrarily, e.g., in the sequence
in which they appear in the text.
Filing of symbols
Where to display graphic symbols—either before all
alphanumeric entries or after them—is not really a crucial
issue. Most indexes containing symbols seem to prefer their
placement at the head of the index, but there are also many
examples of symbols being shown after all verbal headings,
and no amount of pseudological quibbling will result in
convincing arguments for or against one placement or the
other; it matters little, so long as it is explained to users in
The only exception to the rule of disregarding symbols
in filing is the symbol &, the ampersand, which, when not
disregarded, may optionally be filed as if it were spelled out
in the language of the heading.
References
1.
Knight, G. Norman. Indexing, the art of. London: Allen &
2.
American National Standards Institute. Information systems -
Unwin, 1979. 128
coded character set - 7-bit American national standard code
for information interchange (7-bit ASCII}. New York: ANSI,
3.
1986 (ANSI X3.4)
International Organization for Standardization. Information
processing: ISO 7-bit coded character set for information
interchange. Geneva: ISO, 1973. (ISO 646)
Hans H. Wellisch is Professor Emeritus at the College of
Library and Information Services of the University of
Maryland; author of Indexing and Abstracting: an interna
tional bibliography (1980) and Indexing and Abstracting
1977-81
(1984); President of the American Society of
Indexers 1984-5.
an introductory note.
Regarding symbols as parts of verbal headings, all post-
What can we say?
1980 filing rules agree that such symbols (including punc
tuation marks) should be disregarded and the headings filed
"\ would like to plead for an Index in every Excavation
as if the symbols did not.exist. This will primarily affect
quaint pseudonyms that were fashionable in the 18th and
19th centuries, as well as some quirky titles of books,
articles, or poems; neither type of heading is very numer
Report. This is a very simple task, and it can only be done
properly by the writer of the book or monograph. It helps
to avoid repetition in a text; nor does it take time, two or
three hours at most.'
ous. In all cases where the filing of such headings will
result in ambiguous or unfamiliar filing positions, double
entries should be made in which the symbols are spelled
The Indexer Vol. 17 No. 4 October 1991
- Dr Grace Simpson in Journal of Roman Pottery
Studies 3 1990.
241