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@pageheading{left "@value<sectiontitle>", even}
@pageheading{right "A SCRIBE Primer", odd}
@pagefooting{right "66-@value<page>", odd}
@pagefooting{left "66-@value<page>", even}
@comment(@pagefooting{centre "DRAFT @value<date>"})
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@centre[@b<A SCRIBE PRIMER>]
@begin[format]
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@=R.J.Hare@\@=Advisory Service@\@=D
@end[format]
@blankspace[1inches]
@centre[@b(Synopsis)]
This document introduces the use of SCRIBE Version @value(scribeversion)
on the  ICL 2900 series machines (EMAS and BUSH) at ERCC.
The document is not intended to be an exhaustive SCRIBE manual, the
locally produced SCRIBE reference manual @cite[ERCC84b], and the manual
provided by Unilogic @cite[UNILOGIC84] are @b[essential reading] for any
users intending to use SCRIBE for anything other than the simplest of
jobs.
@centre[Prepared using SCRIBE and printed on a Xerox X2700 laser printer]
@centre[@b(Keywords)]
Document formatting, SCRIBE, Text formatting
@newpage
@set[page=1]
@section[Introduction]
@subheading[Background]
SCRIBE is a sophisticated program for the preparation of documents in
several forms.

It is a local implementation of the well known SCRIBE Document
Preparation System, marketed by Unilogic.

Unilogic SCRIBE is implemented locally on the SERC DECsystem-10 and
ERCC VAX/VMS machines.
Access to these implementations of Unilogic SCRIBE may be available to
suitably demanding users in the future, though it is envisaged that the
EMAS and BUSH implementations described here and elsewhere should
adequately satisfy the requirements of most users most of the time.

SCRIBE was written by Brian K. Reid, and was originally distributed to
DECsystem-10 and DECsystem-20 users free through the auspices of the DEC
User's Society.

Eventually, the program was acquired by Unilogic who now handle the
marketing and maintenance of SCRIBE on an extended range of machines and
operating systems.

The SCRIBE instruction format has been accepted by ERCC as a suitable
standard for the preparation of input (manuscript) files for subsequent
formatting by SCRIBE into finished output (document) files.

Unfortunately, no implementation of SCRIBE is available from Unilogic which
will run on ICL 2900 series machines.
Accordingly, a local implementation of SCRIBE has been written.
This implementation does not provide full Unilogic SCRIBE functionality,
but, as implied above, it is intended that it satisfy the requirements of
most users for most of the time.
@subheading[Design Philosophy]
Unlike many other mainframe text processing programs, SCRIBE's design
philosophy is oriented to the idea that the input (manuscript) file to
be processed to produce a finished output (document) file should @b[not]
contain formatting instructions whose effect is immutable, but which
instead specify the required output format in some general way.

SCRIBE itself will then interpret these generalised instructions, and
will generate an output (document) file formatted for the specified
document type and output device.

The necessarily detailed information controlling the interpretation of
individual instructions for each document type and output device is held
in a SCRIBE database and the casual user need never know of the
existence of this database.

For a fuller exposition of SCRIBE's underlying design philosophy, the
user should consult the SCRIBE User Manual @cite[UNILOGIC84] and the
review article @cite[FURUTA82] which describes SCRIBE in the context of
many other mainframe text processors currently in use.

This design philosophy has been largely incorporated in the locally written
implementation of SCRIBE described here.

The article @cite[BROWNING84] describes briefly some of the problems
associated with computerised document preparation and production, though
not in the context of SCRIBE.
@subheading[Overview of Functionality]
SCRIBE allows the user to produce on the computer documents of various types
formatted for a variety of output devices, incorporating within the documents
a variety of text 'objects' or 'environments' and typefaces.

Several standard document types are built into the SCRIBE system, and
sophisticated users may set up their own document types, either from
scratch or, by modifying existing types as required.
The document types supplied as standard are @t[TEXT] (the default),
@t[ARTICLE], @t[REPORT], @t[MANUAL] and @t[LETTER].

Within each document type there exist standard 'environments' which are
formatted automatically by SCRIBE according to both the type of document
being processed and the output device requested.
The demanding user may set up new environments, or modify existing ones
as required.
The standard environments include, 
@t[VERSE], @t[ENUMERATE], @t[QUOTATION], etc.

SCRIBE includes fully automatic sub-systems for setting up pagination and,
for appropriate document types, section numbering, indexes and tables of
contents.

SCRIBE is capable of formatting input (manuscript) files, and producing
output (document) files for four output devices at present, namely
the line printer (@t[LPT]), the Phillips/Mullard GP300 dot-matrix printer
(@t[GP300]), a terminal file (@t[FILE]) and the Xerox X2700 laser printer
(@t[X2700]).

SCRIBE also has sophisticated error handling facilities, and diagnostic error
messages are displayed online as the errors occur.
These messages are also stored in a 'housekeeping' file created by SCRIBE which
may be inspected at leisure when the job is complete.
This file will be named according to the first six characters of the input
(manuscript) file, and will have the 'extension' @t[#ERR].

@section[Running SCRIBE]
SCRIBE forms part of the standard EMAS subsystem, and is therefore
available to all users automatically.
SCRIBE does however require large amounts of internal storage space when
processing large jobs, and in order to accomodate this requirement, your
maximum temporary file size should be increased.
This should be done with the command:
@begin[verbatim]
Command:OPTION AUXSTACKSIZE=256
@end[verbatim]
This procedure is a once and for all operation and does not
need to be re-entered every time you log on or run SCRIBE.
For full details of the @t[OPTION] command, please consult the EMAS 2900
User's Guide @cite[ERCC82].

@need[4]
You may now run SCRIBE by entering the command:
@begin[verbatim]
Command:SCRIBE @b[manuscript],@b[document]
@end[verbatim]
where @b[manuscript] is the name of the input (manuscript) file which contains
the text to be processed and the embedded SCRIBE instructions, and @b[document]
is the processed output (document) file, formatted for the required device.

SCRIBE's consumption of resources is heavy, so it may well be that it will
be necessary to @t[DETACH] any given job to run in the background stream.
Full details of the use of the @t[DETACH] command are given in the EMAS 2900
User's Guide @cite[ERCC82].

The criteria to be considered when deciding whether to run a SCRIBE job 'live'
or in the background stream are:
@begin[itemise, spread 0]
the length of the document

the output device being used
@end[itemise]
Briefly, the longer the document, and the more sophisticated the output device,
the longer will be the amount of CPU time consumed by the job.

The time consumed by a given job may be assessed by using the @t[METER] command
(see reference @cite[ERCC82] for details) immediately before and after
the job concerned, and any job consuming more than about 30 seconds of
CPU time should certainly be run in the background mode.
@section[Using SCRIBE]
Because of its flexibility, use of SCRIBE may be just as simple or as 
complicated as the user requires within the wide range of SCRIBE's functionality.

In its simplest form, use of SCRIBE will consist of merely typing in the
manuscript for a simple document, with blank lines between paragraphs and
perhaps section titles in upper case letters - that is with no SCRIBE
instructions in the file whatsoever.
If such a file is processed by SCRIBE, the result will be a paginated, filled
and justified output (document) file, with line widths, top and bottom margins
etc. selected according to the database entries for the line printer (@t[LPT])
which is SCRIBEs default output device.
The document type will be the default @t[TEXT].

At the other extreme, the sophisticated user may for example be producing a 
large document such as a book with many chapters.
In this case, the input (manuscript) file will consist of the text to be processed
intermingled with whatever SCRIBE instructions are necessary to produce the 
desired effect.

SCRIBE instructions are preceded by an '@t[@@]' character and may be
incorporated intimately in the text, or placed on separate lines as required.
In practice, it is convenient to embed instructions which only have a local effect 
intimately within the text, and those which have an effect extending over
more than one line on a line of their own (the example illustrated in section
@ref[Example] below should make this point clearer).

Whichever of these approaches is adopted, SCRIBEs sophisticated house-keeping
will ensure that if a new chapter, or a chapter with a changed number of pages
(for example) is inserted, it will not be necessary for the pagination of
subsequent chapters to be updated 'by hand'.
This will be done automatically by SCRIBE.

Whichever of these approaches is adopted, the following diagrammatic
illustration of the process of creating a SCRIBE input (manuscript) file,
processing it through SCRIBE to produce an output (document) file, and
finally printing the finished document on the selected output device should
make the whole process clearer.
@begin[format, need 2inches]
@tabclear
@tabdivide[7]
@begin{r8,spacing 3.0 millimetres}
@tabclear
@tabset[0.01 inch, 22 mm, 46 mm, 68 mm, 91 mm, 113.5 mm, 137 mm, 159 mm]
@\@&_@\@=prepares@\@&_@\@\@&_@\@=lists on@\@&_@\
@\|@=New@\|@=using the@\|@=Input@\|@=submitted@\|@=Output@\|@=chosen@\|@=Paper@>|
@\|@=User at the@\|@=--------->@\|@=(Manuscript)@\|@=--------->@\|@=(Document)@\|@=----->@\|@>|
@!@\|@=terminal@\|@=favoured@\|@=File@\|@=to SCRIBE@\|@=File@\|@=output@\|@=Copy@\|@/@\@&_@\@\@&_@\@\@&_@\@\@&_@\
@\@\@=text editor@\@=@\@=@\@=@\@=device@\@\
@end{r8}

@end[format]
@centre[Figure 3.1 Creating a document with SCRIBE]
@section[Example]
@label[Example]
Perhaps the best way to introduce the new user to SCRIBE is to consider its use
in a simple example, explaining briefly the use of the instructions as they are
encountered within the input (manuscript) file.

The example, shown on the following two pages consists of: on the first page,
a simple SCRIBE input (manuscript) file, and on the second page
the final copy produced by printing the resultant output (document) file.

Both the input and the output should be studied carefully in conjunction with
one another and with the aid of the immediately following explanatory notes.

This should give some insight into how a SCRIBE input (manuscript) file is
structured.

Note that although in the following example, SCRIBE instructions are capitalised
for purposes of emphasis, SCRIBE instructions may be entered in either upper or
lower case.
@newpage
@begin[verbatim]
@tabclear
@tabdivide[3]
@@MAKE[TEXT]@\@\@b[;see note 1]
@@DEVICE[X2700]@\@\@b[;see note 2]
@@HEADING[Memo]@\@\@b[;see note 3]
@@SUBHEADING[SCRIBE Service on EMAS and BUSH]@\@b[;see note 4]
@@CENTRE[To all EMAS and BUSH Users]@\@b[;see note 5]
This memo serves to announce the introduction of a SCRIBE service on
EMAS and BUSH.
SCRIBE as implemented on EMAS and BUSH will eventually incorporate
approximately 70% of the functionality of the Unilogic SCRIBE
implementations currently running on the SERC DECsystem-10 and the 
ERCC and @comment[Computer Science ]VAX/VMS machines.

For the benefit of the uninitiated, SCRIBE is a sophisticated text
processing program which allows the user to extend considerable control
over many of the aspects of a document being prepared on the computer.

These include:
@@BEGIN[ITEMIZE]@\@\@b[;see note 6]
choice of output device, eg: LPT, GP300, X2700, etc.

choice of document type, eg: MANUAL, REPORT, LETTER, etc.

choice of different text 'environments' within document types,
eg: TEXT, EXAMPLE, DISPLAY, etc.

choice of typeface, eg: @@B[bold], @@G[greek],@\@b[;see note 7]
@@C[small capitals], etc.

automatic pagination, section numbering and where appropriate
contents page generation

automatic indexing
@@END[ITEMIZE]@\@\@b[;see note 6]
It is hoped that SCRIBE will become the text processor of choice on
EMAS and BUSH for the forseeable future, and, with this hope in mind,
local documentation is in the process of being prepared.
This will comprise:
@@BEGIN[ENUMERATE]@\@\@b[;see note 8]
A 'primer' serving as a brief introduction to SCRIBE, its design
philosophy and use

A 'reference manual' giving a full description of all the facilities
available in SCRIBE as implemented on EMAS and BUSH.
@@END[ENUMERATE]@\@\@b[;see note 8]
Both of these documents will however need to be read in conjunction
with the SCRIBE User Manual @cite[UNILOGIC84] by any user intending to
become a SCRIBE 'wizard', particularly those users who will need
to modify the default settings for line spacing, facecode and 
general document layout etc.
@@FLUSHRIGHT[Roger Hare@\@\@b[;see note 9]
ERCC
@@VALUE[DATE]]@\@\@b[;see notes 9, 10 and 11]
@end[verbatim]
@newpage
@begin[text, spacing 1]
@HEADING[Memo]
@SUBHEADING[SCRIBE Service on EMAS and BUSH]
@CENTRE[To all EMAS and BUSH Users]
This memo serves to announce the introduction of a SCRIBE service on
EMAS and BUSH.
SCRIBE as implemented on EMAS and BUSH will eventually incorporate
approximately 70% of the functionality of the Unilogic SCRIBE
implementations currently running on the SERC DECsystem-10 and the 
ERCC and @comment[Computer Science ]VAX/VMS machines.

For the benefit of the uninitiated, SCRIBE is a sophisticated text
processing program which allows the user to extend considerable control
over many of the aspects of a document being prepared on the computer.

These include:
@BEGIN[ITEMIZE]
choice of output device, eg: LPT, GP300, X2700, etc.

choice of document type, eg: MANUAL, REPORT, LETTER, etc.

choice of different text 'environments' within document types,
eg: TEXT, EXAMPLE, DISPLAY, etc.

choice of typeface, eg: @B[bold], @G[greek],
@C[small capitals], etc.

automatic pagination, section numbering and where appropriate
contents page generation

automatic indexing
@END[ITEMIZE]
It is hoped that SCRIBE will become the text processor of choice on
EMAS and BUSH for the forseeable future, and, with this hope in mind,
local documentation is in the process of being prepared.
This will comprise:
@BEGIN[ENUMERATE]
A 'primer' serving as a brief introduction to SCRIBE, its design
philosophy and use

A 'reference manual' giving a full description of all the facilities
available in SCRIBE as implemented on EMAS and BUSH.
@END[ENUMERATE]
Both of these documents will however need to be read in conjunction
with the SCRIBE User Manual @cite[UNILOGIC84] by any user intending to
become a SCRIBE 'wizard', particularly those users who will need
to modify the default settings for line spacing, facecode and 
general document layout etc.
@FLUSHRIGHT[Roger Hare
ERCC
@VALUE[DATE]]
@end[text]
@newpage
@subheading[Explanatory Notes]
@begin[description]
This is an example of the @t[@@MAKE] instruction which specifies the type of document
to be prepared.
The format is self-explanatory, namely:
@begin[verbatim]
@@MAKE[@b(documenttype)]
@end[verbatim]
where @b(documenttype) is the SCRIBE name for the type of document to be
produced.
Currently, the document types available are:
@begin[description, unnumbered, leftmargin +8, indent -8]
@t[TEXT]@\@t[TEXT] is the default document type - that is, it is what is
assumed to be  required if no @t[@@MAKE] instruction is encountered in
the input (manuscript) file.
@t[TEXT] will be processed to produce filled justified paragraphs, with
the first line indented from the margin and with paragraphs separated by
blank lines.

@t[ARTICLE]@\As @t[TEXT], with the addition of; numbered @t[SECTION]s,
@t[SUBSECTION]s, @t[PARAGRAPH]s and @t[APPENDIX]es; unnumbered
@t[PREFACESECTION]; numbered @t[THEOREM]s, @t[LEMMA]s, etc on numbered
pages.
A table of contents is generated automatically.

@t[REPORT]@\as @t[ARTICLE] with the addition of numbered @t[CHAPTER]s.

@t[MANUAL]@\as @t[REPORT] with the addition of an index.

@t[LETTER]@\Produces a letter. @t[LETTER] has several dedicated
environments such as @t[ADDRESS], @t[GREETING], @t[RETURNADDRESS],
@t[BODY] etc.
@end[description]


This is an example of the SCRIBE @t[@@DEVICE] instruction which
specifies the device for which the output (document) file is to be
formatted.
It has the form:
@begin[verbatim]
@@DEVICE[@b(device)]
@end[verbatim]
where @b[device]
is the SCRIBE device name.
Currently, the devices available are:
@begin[description, unnumbered, leftmargin +8, indent -8]
@t[FILE]@\unpaged terminal file.
The file produced will not incorporate any bold-facing, underlining,
superscripting etc., but is ideal for quick 'proof-reading' at the terminal.

@t[LPT]@\line printer.
This is the default device, that is the device which is selected if no @t[@@DEVICE]
instruction is present in the input (manuscript) file.

@t[GP300]@\The Phillips/Mullard GP300 dot-matrix printer (Warning: there is a real money charge for using this device, please
contact the Advisory service for details of current charges).

@t[X2700]@\The Xerox X2700 laser printer (Warning: there is a real money
charge for using this device, please contact the Advisory service for details
of current charges.
@end[description]


This is an example of a SCRIBE @t[@@HEADING] instruction which has the form:
@begin[verbatim]
@@HEADING[@b[headingtext]]
@end[verbatim]
where @b[headingtext] is the text to be used as a heading.
Other SCRIBE titling or sectioning instructions are; @t[@@MAJORHEADING] and
@t[@@SUBHEADING] which are unnumbered and do not appear in the table of
contents; @t[@@PREFACESECTION] and @t[@@UNNUMBERED] which are unnumbered and do
appear in the table of contents, and; @t[@@CHAPTER], @t[@@SECTION],
@t[@@SUBSECTION], @t[@@PARAGRAPH], @t[@@APPENDIX] and @t[@@APPENDIXSECTION]
which are all numbered and do appear in the table of contents.

This is an example of another of the SCRIBE sectioning instructions described 
briefly in the previous note.

This is an example of the use of the unfilled @t[CENTRE] environment in the form:
@begin[verbatim]
@@@b[environmentname][text to be processed]
@end[verbatim]
where @b[environmentname] is the name of the SCRIBE environment.
There are many environments within SCRIBE, a few of which are described briefly
in the following notes.

This is an example of another of SCRIBE's environments, this time a filled one.
@tag[ItemizeNote]
@t[ITEMIZE] produces an itemised list, each item being marked with a 'bullet'
character (in this case a hyphen).
Note the slightly different form which may be used as an alternative to that
illustrated above for an excursion into any SCRIBE environment:
@begin[verbatim]
@@BEGIN[@b[environmentname]]
   .
text to be processed
   .
@@END[@b[environmentname]]
@end[verbatim]
Note also that although in the processed output, the items are single spaced; in
the input (manuscript) file each item is separated by a blank line.
This is the usual way of separating items/paragraphs etc within a SCRIBE 
environment in the manuscript file.
@blankspace[2.25 lines]
Other filled environments are @t[TEXT] (the default, and the only SCRIBE
environment which is also a document type), @t[DESCRIPTION],
@t[ENUMERATE] (see note @ref[EnumerateNote] below), and @t[QUOTATION].

This line contains examples of shifts into and out of some of SCRIBE's typeface
environments.
Illustrated are shifts into @b[bold], @g[greek] and @c[small capitals]
respectively.
Other typeface environments include @@I (italic), @@P (bold italic), @@U
(underline), etc.

This is an example of a different kind of list (see note
@ref[ItemizeNote] above).
@tag[EnumerateNote]
The @t[ENUMERATE]d list has each item set off from the surrounding text with a 
numeral rather than a 'bullet' character.
@t[ENUMERATE] is another example of a SCRIBE filled environment.
Both @t[ENUMERATE]d and @t[ITEMIZE]d lists may be nested to the required level,
each level having a different 'bullet' character or numbering style.
The 'bullet' character and numbering style repeat after the second and third
levels of nesting respectively.

This is an example of the unfilled @t[FLUSHRIGHT] environment.
The name is more or less self explanatory, each line in the input (manuscript)
file is flushed against the right hand margin in the output (document) file.
There is also a @t[FLUSHLEFT] environment.

This is an example of the use of the @t[@@VALUE] instruction.
The argument to the @t[@@VALUE] instruction may either be a user-defined
string set up with an @t[@@STRING] instruction:
@begin[verbatim]
@@STRING[@b[name]="@b[text]"]
@end[verbatim]
where @b[name] is the users name for the string @b[text], or a predefined
string, several of which exist within SCRIBE.
@t[DATE] is a predefined string, others are @t[TIME], @t[YEAR], @t[TIMESTAMP], @t[SECTIONNUMBER],
@t[SECTIONTITLE] etc.

Note the nesting of one SCRIBE environment or instruction within another
environment (the @t[@@VALUE] instruction within the @t[@@FLUSHRIGHT] environment).
This is quite acceptable within SCRIBE, and generally, any instruction or 
environment may be nested within another environment.
The nesting of environments in particular may be carried to an arbitrary level,
but it is the responsibility of the user to ensure that such nesting is
actually sensible!
@end[description]
@section[Where To Go From Here?]
Well, the first thing you should do is to try using SCRIBE on a short
simple file - an internal memo say, or a handout for a lecture.

Then you could try inserting SCRIBE instructions one at a time, starting
with say an @t{@@DEVICE[GP300]} or @t[@@DEVICE<X2700>] instruction in
order that you can see how much nicer the output from a high quality
printer is than that from a line printer (though in general, it is good
practice to use the line printer or a terminal file for all but the
final drafts of any document).
In order to see a sample of the character sets (fonts available) with
the GP300 printer, please consult reference @cite[ERCC84a] - at this
stage you are @b[not] recommended to try changing fonts within SCRIBE
other than by using the typeface instructions - this is not a suitable
exercise for new users.

Also, be warned that a real money charge is made on a per sheet basis
for using the GP300 and X2700 printers.
For details of current charges, please consult the Advisory Service.

As you gradually increase the complexity and number of SCRIBE
instructions in your file, you should be able to see how SCRIBEs
powerful facilities will enable you to produce documents formatted more
or less at will.

Once you have exhausted the facilities briefly described or mentioned in
passing in this primer, you should study the companion SCRIBE Reference
Manual @cite[ERCC84b] and if you require even further information about
SCRIBE you should graduate to the SCRIBE User Manual @cite[UNILOGIC84]
which contains fuller descriptions of SCRIBE's facilities than are
included in the locally produced Reference Manual.

The additional facilities described in the Reference Manual include:
@begin[itemize,need 8.4]
indexing

cross-referencing to other sections within a document

tabulation

page headings and footings

modification of existing, and, definition of new environments

control of overall document style
@end[itemize]

If you eventually feel that SCRIBE as implemented on EMAS does not have
enough facilities for your application (and this should not happen often!),
you should consider using the implementations of SCRIBE on either the SERC
DECsystem-10 or the ERCC VAX/VMS.
Facilities exist for the remote use of Unilogic SCRIBE on both of these
machines, and for direct use on the ERCC VAX/VMS.
For further information on these facilities, please contact the Advisory
Service.
@section[Typography and Typesetting]
Finally, a few words on the terminology and practices of typography and
typesetting are probably in order.
These brief notes are based on the relevant sections of the
Manual "Getting Started on the Lasercomp" @cite[lasercomp].
@subheading[Terminology]
@define[ssh=subheading, flushleft, above 1, below 0]
@ssh[Picas and Points]
Picas and points are units of distance traditionally used in the
printing trade.
there are 6 picas to the inch, and 12 points to the pica.
It follows that there are 72 points per inch.

@ssh[Ascenders, Descenders and x-Height]
Ascenders and descenders are respectively those parts of a character
(usually a letter which extend above the x-height or below the baseline
of a line of type, eg: the 'top' portion of a 't' or an 'h' are
ascenders, and the tails of a 'y' or a 'g' are descenders.


The x-height of a particular typeface is the height of those characters
which have neither ascenders nor descenders, eg: 'a'.
@ssh[Point size]
The size (height) of type is usually expressed in points.
In principle, the point size is the distance from the top of the highest
ascender to the bottom of the lowest descender, though in practice
the convention adopted for different typefaces may be different.
@ssh[Baseline]
The baseline is an imaginary horizontal line upon which the characters
in a line of typesetting are considered to rest.
@ssh[Leading]
Leading is the distance from one baseline to the next (above or below),
expressed in points.
Effectively this is the line spacing of the text.
The leading may be the same as the point size, but increasing the
leading can make the text easier to read.
The amount of extra leading required varies according to the typeface in
use and the length (measure) of the line of text, usually a leading
one or two points greater than the point size will suffice.
Leading and point size are often expressed together using the compound
term:
@begin[quotation]
"point size" on "leading"
@end[quotation]
for example, "10 on 12" meaning a 10 point typeface used with a 12 point
leading or line spacing.
@ssh[Measure]
The measure is effectively the length of the line in the processed text.
@ssh[Typeface and Fonts]
A font is a set of characters designed together, eg: Kosmos 10 point.
A typeface is a family of fonts designed to be used together, eg:
Kosmos 10 point, Kosmos 10 point italic, Kosmos 10 point bold.
The devices available from within SCRIBE do not allow the use of very
many typefaces or fonts because of their limited capacities.
@ssh[Filling and Justification]
Filling id the process whereby the line of processed text has as many
words placed on it as possible, without crossing over the boundary
of the right hand margin.
Justification is the process whereby each line of filled text is
made the same length as every other by varying the amount of white
space between words on the line.
The end result is that both the left and right margins are straight, 
and (usually) that the length of the line will be equal to the
measure.
@subheading[Introductory Notes on Typography]
@ssh[Choice of Typeface]
The typeface chosen for any job should as far as possible be suited
to the requirements of the job.
Some characteristics of different typefaces are enumerated:
@begin[enumerate]
Serif or sans-serif.
A sans-serif typeface such as Kosmos should not be used in the body
of a long text or in long reports.
Itis difficult to read and may cause eye strain.
@blankspace[2]
Having said this, bear in mind that the 'serifs' in a sans-serif typeface
may 'fill-in' depending on the method of reproduction being used.
This manual is Xeroxed, and a sans-serif typeface is used.

The 'set' of the typeface being used should be considered.
This is determined by the width of the lower case 'm'.
Some typefaces are much wider than other, this fact becoming more
obvious the larger the point size used.
In general, typefaces with narrow sets are to be preferred for column
work.

Typefaces with large x-heights require more leading.

Some typefaces are darker than others.

Some typefaces are better when used in larger sizes, and some when
used in smaller sizes.

Many jobs require italic and bold fonts as well as the Roman
font.
Care should be taken when mixing fonts from different typefaces.
@end[enumerate]
@ssh[Measure]
@begin[enumerate]
Type set with too long a measure is difficult to read.
A measure should ideally have an average of 65-70 characters.
When setting for A4 paper (the only size available on ERCC
high quality printers), it may be desirable to increase the 
size of margins to achieve this goal.

Too short a measure may produce an unacceptable amount of white space
between words.
@end[enumerate]
@ssh[Point Size]
@begin[enumerate]
9, 10 and 11 are suitable point sizes for normal text work.

Beginners often make headings too large.

Dictionaries and catalogues are specialis publications whose
requirements may differ from the norm.
A small point size may be acceptable because only specific 
entries, not large bodies of text are being read.

Footnotes are usually set two points smaller than that of the main text.
@end[enumerate]
@ssh[Leading]
@begin[enumerate]
Judiciouse use of leading can aid legibility.
It can also alter the aesthetic effect of a typeface.
The denser a typeface is set, the blacker it appears.

Proportionally, more leading is required when using larger point sizes.
Similarly, the wider the measure, the more leading is required.
Readability is the crucial consideration

Large bodied typefaces usually benefit from a leading of 1.5-2 points
greater than the point size of the typeface.
@end[enumerate]

@section[References And Further Reading]
@begin{bibliography}
Browning@tag[browning84] G.K.S., Automatic Typesetting., University Computing,
Vol @b[6], No 2, pp 95-98, 1984.

Furuta@tag[furuta82] R., Scofield J., Shaw A., Document Formatting
Systems: Survey, Concepts and Issues, ACM Computing Surveys, Vol @b[14], No 3,
pp 417-472, September 1982.

Hamilton-Smith@tag[ercc82] N., Murison J.M. (editors), EMAS 2900: User's Guide,
ERCC, October 1982.

Hare@tag[ercc84b] R.J., McArthur C.D., McKendrick A., SCRIBE Reference Manual,
ERCC User Note 67, March 1985.

Murison@tag[ercc84a] J.M., Phillips GP300 Printer: Character Sets, ERCC User
Note 50, October 1984.

Oxford University Computing Service, Getting Started on the Lasercomp, 
June, 1983.@tag[lasercomp]

Reid@tag[unilogic84] Brian K., SCRIBE Document Preparation System - User
Manual, Unilogic Ltd.,
April 1984.
@end[bibliography]