JTC1/SC2/WG2 N2632
Date: 2003-09-30

Proposal to Encode Phonetic Symbols with Middle Tilde inthe UCS
Date:

2003-09-30

Author:Address:

Peter Constable, Microsoft
One Microsoft Way
Redmond, WA 98052
USA+1 425 722 1867
petercon@microsoft.com

Tel:
Email:

A. Administrative
1.
2.
3.
4.
5.
6a.
6b.

Title
Requester’s name
Requester type
Submission dateRequester’s reference
Completion
More information to beprovided?

Proposal to Encode Phonetic Symbols with Middle Tilde in the UCS
INCITS/L2, UTC, SIL International (contact: Peter Constable)
Expert contribution
2003-09-30
L2/03-174r
This is a complete proposal
Only as required for clarification.

B. Technical—General
1a. New Script? Name?
1b. Addition of characters to existing block?
Name?
2. Number of characters in proposal
3. Proposed category
4. Proposed level of implementation andrationale
5a. Character names included in proposal?
5b. Character names in accordance withguidelines?
5c. Character shapes reviewable?
6a. Who will provide computerized font?
6b. Font currently available?
6c. Font format?
7a. Are references (to other character sets,dictionaries, descriptive texts, etc.) provided?

No
Yes — Phonetic Extensions
11A
1 (no combining marks or jamo)
Yes
Yes
Yes
SIL International
Yes
TrueType
Yes

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JTC1/SC2/WG2 N2632
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7b. Are published examples (such as samples
from newspapers, magazines, or othersources) of use of proposed characters
attached?
8. Does the proposal address other aspects ofcharacter data processing?

Yes

Yes, suggested character properties are included (see section E).

C.

Technical—Justification

1.

Has this proposal for addition of character(s) No
been submitted before?
Has contact been made to members of theYes
user community?
With whom?
Linguists
Information on the user community for theLinguists
proposed characters is included?
The context of use for the proposed characters Linguistics text books, linguistic descriptions (books, journalpublications, etc.); dictionaries.
Are the proposed characters in current use by Yes
the user community?
Must the proposed characters be entirely in
Preferablythe BMP?
Rationale?
If possible, should be kept with other phonetic symbols in theBMP.
Should the proposed characters be kept
Preferably
together in a contiguous range?
Possibly (see discussion in section F below)
Can any of the proposed characters be
considered a presentation form of an existing
character or character sequence?
Rationale for inclusion?
See discussion in section F below.
NoCan any of the proposed characters be
considered to be similar (in appearance orfunction) to an existing character?
Rationale for inclusion?
n/aDoes the proposal include the use ofNo.
combining characters and/or use of composite
sequences?
Does the proposal contain characters with any No.
special properties?

2a.
2b.
3.
4.
5.
6a.
6b.
7.
8a.

8b.
9a.

9b.
10.

11.

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D. SC2/WG2 Administrative
1.
2.
3.
4.

Relevant SC2/WG2 document numbers
Status (list of meeting number andcorresponding action or disposition)
Additional contact to user communities,
liaison organizations, etc.
Assigned category and assigned priority/timeframe

Other commentsE.

Proposed Characters

A code chart and list of character names are shown on a new page.

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Date: 2003-09-30

E.1

Code Chart
1D6 1D70



1



2



3



4



5



6



E.2
1D6C
1D6D
1D6E
1D6F
1D70
1D71
1D72
1D73
1D74
1D75
1D76

789ABCDEF

Proposal to Encode Phonetic Symbols with Middle Tilde in the UCS Page 4 of 10Peter G. Constable September 30, 2003 Rev: 2Character NamesLATIN SMALL LETTER B WITH MIDDLE TILDELATIN SMALL LETTER D WITH MIDDLE TILDELATIN SMALL LETTER F WITH MIDDLE TILDELATIN SMALL LETTER M WITH MIDDLE TILDELATIN SMALL LETTER N WITH MIDDLE TILDELATIN SMALL LETTER P WITH MIDDLE TILDELATIN SMALL LETTER R WITH MIDDLE TILDELATIN SMALL LETTER R WITH FISHHOOK ANDMIDDLE TILDELATIN SMALL LETTER S WITH MIDDLE TILDELATIN SMALL LETTER T WITH MIDDLE TILDELATIN SMALL LETTER Z WITH MIDDLE TILDEJTC1/SC2/WG2 N2632
Date: 2003-09-30

E.3

Unicode Character Properties

All of these characters should have a general category of Ll; no case mappings for these characters are proposed.
Other properties should match those of similar characters (e.g. U+026B LATIN SMALL LETTER L WITH MIDDLETILDE).

F.

Other Information

F.1

Rationale

In phonetic transcription, consonant symbols with overlaid tilde are generally used to represent consonants withvelarized or pharyngealized articulation. In the Americanist phonetic tradition, overlaid tilde has been used only for
simultaneous velar articulation. In the IPA tradition, overlaid tilde has been used for either velarization orpharyngealization. There is a newer IPA recommendation for transcribing velarization and pharyngealization in
distinct ways using modifier letters:

Figure 1. Distinct IPA notation for velarized and pharyngealized articulation (IPA 1999, p. 204).

Overlaid tilde is still approved IPA usage, however:

Figure 2. Overlaid tilde: current IPA usage (IPA 1999, p. 204).

Figure 3. Overlaid tilde: current IPA usage (IPA 1999, p. 173).

It is probably the case that the former notation is becoming the more common, both because it is more explicit, andbecause it poses fewer problems typographically. Nevertheless, symbols with overlaid tilde are still encountered inlinguistics reference books and phonetics textbooks, and also in language descriptions:Figure 4. From IPA (1949), p. 14.

Figure 5. From Heffner (1950), p. 134.

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Figure 6. From Floyd (1981), p. 102.

Figure 7. From Catford (1988), p. 110.

Figure 8. From Laver (1994), p. 559.

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Figure 9. Overlaid tilde used in African-language descriptions (Mann and Dalby 1987, p. 218).

Figure 10. Overlaid tilde used in African-language descriptions (Tucker 1971, p. 647).

While it is clear that characters with overlaid tilde are used, what is more difficult to assess is the inventory of suchcharacters needed. After “ɫ” (for the “dark l” of English), these characters appear to be most frequently used inrelation to Arabic (for pharyngealized “emphatic” consonants) and other Semitic languages; and following that, for
Russian (some describe Russian palatalized consonants as contrasting with velarized counterparts). Velarizationand pharyngealization do occur in other languages, yet not all languages have been described, and not all existing
descriptions can be examined. Therefore, while the possibilities for base characters that may require a modifier toindicate these secondary articulations are limited to at most the phonetic symbols for consonants, it is not clear just
how many of those are actually required.
Because velarization is said to contrast with palatalization in Russian, and because Russian has a large inventory ofpalatalized consonants, it may constitute a language requiring one of the larger inventories of consonants withvelarized modification. Such an inventory for Russian is described in IPA 1949:

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Date: 2003-09-30

Figure 11. Inventory of Russian velarized phones (IPA 1949, p. 28).

This corresponds almost exactly with the inventory of overlaid-tilde characters I have encountered in the linguistics
literature I have surveyed, and that are evidenced in the examples shown above, as summarized in Table 1:
Base Character
pbmfv
tdnlr
ɾsz

SamplesFigure 5
Figure 5
Figure 6
Figure 6(not encountered)Figure 4, Figure 5, Figure 7, Figure 9, Figure 10
Figure 3, Figure 4, Figure 5, Figure 7, Figure 9
Figure 3, Figure 6, Figure 8
Figure 2, Figure 6, Figure 7, Figure 8, Figure 9
Figure 9
Figure 8
Figure 4, Figure 6, Figure 7, Figure 9, Figure 10
Figure 4, Figure 6, Figure 7, Figure 9

Table 1. Base characters and samples in which they appear with overlaid tilde1

Of the base characters listed in IPA 1949 in relation to Russian velarized consonants (Figure 11), all are attested in
the literature I surveyed except “v”.
I have encountered descriptions of Hebrew and Arabic that cite pharyngealization of other consonants — ð, k, andʔ — but these descriptions did not use the overlaid-tilde notation. It is my impression that these consonants are notmentioned as often in Arabic and Hebrew descriptions in relation to pharyngealization as are others, particularly t,d and s.
It appears, then, that those characters with overlaid tilde that are illustrated in the samples above are probably theinventory that are most likely to be used by linguists. Therefore, I am limiting the proposed inventory to just thosefor which attestation can be demonstrated at this time. It is possible that a need for others may come to light atsome point in the future, though that is not anticipated at present.

1

Note: Some of the sources from which these samples were taken included overlaid tildes with other base characters than what thegiven sample reflects. The overall inventory encountered is that shown in the table, however.

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F.2

Representation as sequences with U+0334

Question 8a of section C above asks whether these characters can be considered presentation forms of existing
characters or character sequences. They could possibly be viewed as sequences involving U+0334 COMBINING
TILDE OVERLAY, but I suggest that this would be inappropriate and is irrelevant. While combining marks ingeneral are assumed to be applicable to arbitrary characters in a generative manner, allowing dynamic
representation of text elements such as Latin small a with bridge below, there are certain combining marks for which
this is not appropriate. I suggest that U+0334 COMBINING TILDE OVERLAY is among them.
Linguistically, there simply are only certain base characters that have any likelihood of being modified with a tildeoverlay. There are far more characters, even when limiting discussion to phonetic symbols, for which there would
be little motivation to add a tilde overlay. For instance, it would be silly (for typographic reasons as well as linguistic)
to encode a character sequence < U+026B LATIN SMALL LETTER L WITH MIDDLE TILDE, U+0334
COMBINING TILDE OVERLAY >. In practice, there is a very limited inventory of characters that are used withtilde-overlay modification, because there are very few speech sounds that can have velarized or pharyngealized
secondary articulation.
Also, whereas it is feasible to create font/rendering implementations that can productively display sequences
involving arbitrary base characters followed by a combining mark such as U+0300 COMBINING GRAVE ACCENT
using mechanisms such as glyph attachment points, this is not as readily feasible for U+0334 COMBINING TILDEOVERLAY: the way in which a base character is modified using a tilde overlay is dependent on the particular basecharacter involved. It may be necessary to have different attachment positions, tildes of varying sizes and shapes,
and possibly even adjustments to the design of the outline for the base character. Such issues cannot be dealt withby a font developer in a generalized manner but must be handled on an individual basis.
Thus, in terms of usage requirements and the realities of implementation, dynamic composition using U+0334
COMBINING TILDE OVERLAY is not a good choice, and should be avoided.
Note that this view is corroborated by existing characters in Unicode itself in that the characters U+026B LATIN
SMALL LETTER L WITH MIDDLE TILDE does not have a decomposition. The combining mark U+0334
COMBINING TILDE OVERLAY is not currently used in any decomposition.
Therefore, since there are good reasons why productive use of U+0334 COMBINING TILDE OVERLAY is notrecommended, and insofar as existing characters with tilde overlay are not considered presentation forms ofexisting sequences, it is suggested that the characters proposed here are likewise not to be considered presentation
forms of existing sequences.

G. References
Catford, J.C. 1988. A practical introduction to phonetics. Oxford: Clarendon Press.
Floyd, Rick. 1981. Manual for articulatory phonetics. Dallas: Summer Institute of Linguistics
Heffner, R-M. S. 1950. General phonetics. Madison, WI: University of Wisconsin Press.
International Phonetic Association (L’association Phonétique Internationale). 1946. “parti administratiːv.” Lemaître phonétique 85:1, p. 16–7.
——. 1999. Handbook of the International Phonetic Association. Cambridge: Cambridge University Press.
Laver, John. 1994. Principles of phonetics. (Cambridge textbooks in linguistics.) Cambridge: Cambridge UniversityPress.
Mann, Michael, and David Dalby. 1987. A thesaurus of African languages: a classified and annotated inventory of thespoken languages of Africa with an appendix on their written representation. London: Hans Zell Publishers.
Tucker, A.N. 1971. “Orthographic systems and conventions in Sub-Saharan Africa.” Current trends in linguistics,
volume 7: Linguistics in Sub-Saharan Africa, ed. by Thomas A. Sebeok, 618–53. The Hague: Mouton.
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