Sonneb issi was a hand-based means of communication used by Tibetan and Burmese-speaking Buddhist monks in the 11-14th centuries. It was used by those who had taken a vow of silence, or to talk with deaf, mute and/or blind people. It was also used to record the original pronunciation of scriptures such as the Tripitaka, from which the spoken language had begun to diverge. The page describes the system used for Tibetan, but it was modified for other languages including Burmese.
The system was unusual in being regular and based on phonetic principles. For consonants, thumb would touch one of the other fingers, and the position of against the finger represented the place of articulation, i.e. where the tongue made contact with the roof of the mouth, or the lips pressing together. Thus touching the tip of the finger represented the bilabial consonants /p/, /pʰ/ (aspirated p), /b/ or /m/ (depending on the finger, top finger was /p/). Further back, touching the first joint represented the dental consonants /t/, /tʰ/, /d/ or /m/.
Sibilants (/ s/, /ʃa/, /ʒa/, /za/ were represented by the finger approaching the place of articulation but not touching, and waved from side to side if necessary for clarity. Affricates started touching and moved downward.
Vowels used the fingers, held together, to represent the vocal cavity. /i/ was near the tip of the first finger, and /u/ need the base of that finger. /a/ was in the centre of the little finger. /e/ and /o/ were on the second finger, below /i/ and /u/ respectively. Lax vowels were more centralized. Glides (diphthongs) were simple slides from one vowel position to another.
Tones were represented by the height of the hand.
Sometimes two fingers were used together to represent a consonant, for example a sound which could be pronounced /s/ or /z/ would use both the first and second fingers, or unvoiced nasal consonants in Burmese would use the first finger (for unvoiced) and the little finger (for nasalized).
References
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