================================================================
Archimedes Palimpsest encoding scheme for digital transcriptions
================================================================

:Authors: Alex Lee,  Doug Emery
:Date: April 7, 2010

.. contents::

Included transcriptions
=======================

The digital product includes the following transcriptions reporting the
readings of the manuscript undertext:

	================================ ============================
	Text                             As read by
	================================ ============================
	Equilibrium of Planes (PE)       Netz-Wilson
	Floating Bodies (FB)             Netz-Wilson, Heiberg
	Measurement of the Circle (DC)   Netz-Wilson
	Method (ME)                      Netz-Wilson, Heiberg
	Sphere and Cylinder (SC)         Netz-Wilson
	Spiral Lines (SL)                Netz-Wilson, Heiberg
	Stomachion (ST)                  Netz-Wilson, Heiberg
	Hyperides (HYP)                  ZPE publication
	================================ ============================

Transcriptions are available both as full treatises (e.g.
``FloatingBodies-NW-p5.xml``) or as individual folios (e.g.
``017r-016v_Arch07r_Tei_Netz-Wilson.xml``).

TEI conformance
===============

These transcriptions are presented as XML files conforming to the `TEI
P5 standard`_. The purpose of this document is to describe the
encoding decisions specific to these transcriptions; for all other
issues, the TEI standards should be consulted.

Only a subset of the available TEI modules are used in these
transcriptions: core, header, textstructure, analysis, figures, linking,
transcr, and gaiji.

The TEI `Roma`_ generator has been used to generate a `RelaxNG`_ schema
for validating the transcriptions. The Roma customization file is
provided as ``archie-tei.xml``; the schema file is ``archie-tei.rng``.

.. _TEI P5 standard: http://www.tei-c.org/
.. _RelaxNG: http://www.relaxng.org/
.. _Roma: http://www.tei-c.org/Roma/

Overall structure (``div``, ``milestone``, ``head``, ``ab``, ``lb``)
====================================================================

For treatises that are divided into books (e.g. FB), the content for
each book has been enclosed in a ``div[@type="book"]`` element. Other
treatises have their content directly within the ``body`` element.

The content itself comes as a series of ``milestone``, ``head``, and
``ab`` elements. Here the milestones indicate units of text such as
postulates or propositions. These are presented according to Heiberg's
edition.

Each ``head`` or ``ab`` element contains the words of the
transcription.  Preceding each line of transcription is an ``lb``
element, whose ``@n`` attribute indicates the number of the line that
follows.  Lines are numbered according to each column of the undertext
folio.

Within the ``head`` and ``ab`` elements there occur two further types of
milestones. Those of type "folio" indicate the overtext (= Euchologion)
folio number and undertext column number, e.g. *81v1*. Those of type
"underTextFolio" indicate the undertext (= Archimedes or Hyperides)
folio number, e.g. *Arch03v*.

In most cases, the undertext folio milestone will be followed by four
overtext folio milestones. For example, *Arch03v* is composed of
*81v1, 88r1, 81v2, 88r2*.

Words (``w``, ``unclear``, ``supplied``)
========================================

If a word has no further markup associated with it, it is simply
provided as text, e.g. "ὥστε τῶν μέρων". But if a word has any extra
markup, it is contained within a ``w`` element. *NB. All textual
whitespace at any level within a `w` element is to be ignored or
discarded.*

The tags ``unclear`` and ``supplied`` never span across words;
instead, separate tags are used for each word. So, for example, "κ̣α<ί
ἐ>στι" would be encoded as::

	<w>
		<unclear>κ</unclear>α
		<supplied reason="lost">ί</supplied>
	</w>
	<w>
		<supplied reason="lost">ἐ</supplied>στι
	</w>

Line breaks
-----------

When a word breaks across a line, it is presented in two parts, the
initial ``w[@part="I"]`` and the final ``w[@part="F"]``, with the
line break ``lb`` placed between. For example, given this text::

	5 ... ... ... συνε-
	6 χέων ... ... ...

the corresponding markup would be::

	... <w part="I">συνε</w>
	<lb n="6"/><w part="F">χέων</w> ...

Here the word συνεχέων breaks with συνε at the end of line 5 and is
completed by χέων in line 6.

In cases where a preceding or following folio is missing, it is possible
that a word-part will lack its complement.

Abbreviations (``choice``, ``abbr``, ``am``, ``g``, ``expan``, ``ex``)
======================================================================

All abbreviations are encoded as ``choice`` elements. Each ``choice``
element contains an ``abbr`` element giving the manuscript form of the
word and an ``expan`` element giving the editorially expanded form of
the word.

Partial-word abbreviations
--------------------------

For abbreviations in which only a portion of the word has been
abbreviated, such as "ἔχο(ν)", the entire word is represented by the
``choice`` element. An ``am`` element is used in the ``abbr`` to show
where the abbreviation occurs, and a corresponding ``ex`` gives the
expansion within the ``expan``. The ``am`` always contains a single
``g``, to represent whatever symbol was used for the abbreviation.
(No details are given about the symbols used, though this would be a
nice addition to the transcriptions down the road.)

::

	<choice>
		<abbr>ἔχο<am><g/></am></abbr>
		<expan>ἔχο<ex>ν</ex></expan>
	</choice>

Here an enclosing ``w`` element is optional.

Multiple ``am`` and ``ex`` instances are possible, so long as they
occur in pairs. The doubly abbreviated word "τ(ου)τ(έστιν)" would be
encoded as::

	<choice>
		<abbr>τ<am><g/></am>τ<am><g/></am></abbr>
		<expan>τ<ex>ου</ex>τ<ex>έστιν</ex></expan>
	</choice>

If the abbreviation has been flagged by the editors as ``supplied`` or
``unclear``, these tags will go outside of the ``am`` and the ``ex`` (it
is not permitted by the schema to have them within those elements, nor
would this have any clear meaning).

Full-word abbreviations
-----------------------

For many common, short words, the entire word is represented with a
symbol. In such cases any extra markup, such as ``supplied`` or
``unclear``, is placed outside of the choice. For example, suppose that
a symbol representing the word καὶ has been supplied by the editors; the
word is demanded by the context, and the manuscript shows only a
one-character space, so an abbreviation is necessary. The word would be
encoded as::

	<supplied reason="lost"><choice>
		<abbr><am><g/></am></abbr>
		<expan><ex>καὶ</ex></expan>
	</choice></supplied>

Abbreviations at word breaks
----------------------------

One final complication occurs when an abbreviated word occurs at a line
break. Here the word is divided into two parts, ``w[@part="I"]`` and
``w[@part="F"]``, as mentioned above. When one of those parts contains
an abbreviation, its entire contents will be contained within a
``choice``.

So, given the following text::

	1 ... ... ... ἔχ(ου)-
	2 σαν ... ... ...

the corresponding markup would be::

	<w part="I"><choice>
	<abbr>ἔχ<am><g/></am></abbr>
	<expan>ἔχ<ex>ου</ex></expan>
	</choice></w>
	<lb n="2"/><w part="F">σαν</w>

Because the initial part of the word, before the line break, contains an
abbreviation, its entire contents are given in a ``choice`` element. The
final part of the word, which resumes after the line break, needs no
``choice`` because it does not contain an abbreviation.

Encoding of other features (``hi``, ``figure``)
===============================================

The manuscript contains marginal numbers (typically indicating a
proposition), as well as a few instances of marginal text. These are
enclosed within ``hi[@rend="margin"]`` elements.

Cases of raised text are enclosed within ``hi[@rend="superscript"]``
elements.

Diagrams are represented with ``figure`` elements, each of which has an
``@n`` attribute and a short ``figDesc`` within it. Note that these
elements are also included when the manuscript merely contains space for
a figure, even though no figure has been drawn in.

Some features of the manuscript, including large text, extra spaces, and
out-dented text, have not been included in this transcription.

Editorial additions
===================

All diacritics, word spacing, and punctuation are editorial additions.
Punctuation always appears within ``pc`` tags (so that punctuation can
easily be stripped out if so desired).

On occasion the reading in the manuscript is such that it could be taken
for an error in the transcription (for instance if there has been
scribal error or some other form of corruption). These readings have
been flagged with a ``sic`` element. Such elements can span multiple
words.

Whitespace
==========

As mentioned above, in certain elements whitespace must be ignored. This
can be accomplished, in XSLT for instance, by the following template::

	<xsl:template match="w/text()|unclear/text()|supplied/text()|choice//text()">
		<xsl:value-of select="normalize-space(.)"/>
	</xsl:template>

The need for this workaround is regrettable, but it seems to be the
most robust way of accounting for the whitespace-handling behaviors of
various XML tools.

Linking to text images for individual folios (``facsimile``, ``surface``, ``graphic``, ``zone``)
================================================================================================

Each individual folio transcription (e.g.
``017r-016v_Arch07r_TEI_Netz-Wilson.xml``) is mapped to the
accompanying images of the corresponding folio using the ``facsimile``
section following the TEI header. A single ``surface`` element is
used, containing one ``graphic`` element for each image file and one
``zone`` element for each mapped line or other element (such as
figures, and identified proposition and book enumerations). The
following shows a portion of a facsimile element.

::

    <facsimile>
       <surface ulx="0" uly="0" lrx="8160" lry="10880">
          <graphic url="014r-019v_Arch02r_Sinar_LED365_01_pack8.tif"/>
          <graphic url="014r-019v_Arch02r_Sinar_LED445_01_pack8.tif"/>
          <!-- ... -->
          <zone lrx="3404" lry="1140" ulx="1052" uly="834" xml:id="zArch02r_14r1_01"/>
          <zone lrx="3404" lry="1380" ulx="1052" uly="1138" xml:id="zArch02r_14r1_02"/>
          <!-- ... -->
       </surface>
    </facsimile>

The ``surface``'s ``@ulx``, ``@uly``, ``@lrx``, and ``@lry``
attributes provide the pixel dimensions of the images referenced by
the enclosed graphic elements. The ``zone``'s ``@ulx``, ``@uly``,
``@lrx``, and ``@lry`` attributes describe a box containing the
referenced component.  The ``zone/@xml:id`` begins with "z", followed
by the undertext folio, prayer book folio and column (if applicable),
and the ``@n`` attribute value of the referenced element. Elements
that are not lines, such as figures, have the element type in the ID
in lieu of the column number, for example: ``zArch02r_14r_fig_1``.

In the text portion of the file, each mapped element will employ the
``@facs`` attribute to reference the corresponding ``zone`` by its
``@xml:id``, as follows::

    <ab><milestone n="14r1" unit="folio"/>
       <lb n="1" facs="#zArch02r_14r1_01"/><w part="F"
          >φο<unclear>τέ</unclear>ρ<supplied reason="lost">ου</supplied></w> τᾶς