Tonal Notation of Indic scripts in Mainland Southeast Asia

(35) c¯pWA:{cii pwaa:} ‘prosperity’ (l.1.)
nH`luM{nha
luM} ‘heart’ (l.2.)
s˘t`N¸suM{si
tang’suM} ‘(of monks) reside at a certain place’ (l.5.)
tuik¸tW`n’{tuik’twan’}
‘urge’ (l.7.)
ekAN¸{kong’} ‘good’ (l. 7,9.)
etAN¸{tong’} ‘ask, beg’ (l.10.)
kYâlW`n’{kyuu
lwan’} ‘violate’ (l.10.)
In the ink inscription, also the tonal distinction of the open rhymes
/-E/, /-O/ had already been reflected in the spellings. Here we will get
the tonal notation system almost same as in modern orthography, with
the difference that {-:} has not been extended to other rhymes yet.
Conclusion
In Modern Thai script, the indication of tone class are done exclusively
by a distinct set of tone marks. Indeed one-to-one correspondence
between tone marks and tones was lost due to the tonal bifurcation, but
each tone mark uniquely represents a tone, as far as a single group of
initial consonant is concerned. Tone marks are independent of notations
of (non-checked) rhyme.
On the other hand, in Burmese script tone classes are indicated
partly by the selection of a vowel sign, and partly by the addition of
a tone mark. Unlike Thai script, the occurrence of tone marks depends
on the (non-checked) rhyme.
The difference in nature of two tonal notation systems stems from
their different provenances. Since none of Thai tone marks find its
source in the Khmer script, they must be newly invented to represent
tones not found in Khmer language. Although new members were
added to the set, the nature of tone marks has remained unchanged.
On the other hand, tone marks of Modern Burmese script trace back
to glyphs for segmental sounds in Mon script. To transcribe some phonetic
feature of a tone, putting aside whether it is principal or concomitant,
Burmese of the time utilized the notation of Mon segmental sound
which is heard similarly.
To transcribe the phonetic feature of Creaky tone, whether glottal
stop or laryngealization, Burmese script introduced ‘short’ vowel symbols
and/or {-@’} from Mon script, together with variance among them.
To breathiness, the phonetic feature of Heavy tone in open rhymes, it introduced
{-h’}/{-:} which were used for /-h/ in Mon script. 22
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