Siddham Cha 𑖔

Cha is the aspirated partner of the letter that heads the palatal class, and it holds the second slot exactly as the velar aspirate does in the class before it. The pair are learned together as the voiceless half of the group, and the relationship between them is one feature and nothing else.

Sanskrit uses the letter considerably less than its unaspirated partner. Its place is fixed by the shape of the table rather than by the vocabulary, which is a pattern repeated throughout the consonant section: an arrangement by articulation gives every crossing of place and feature a slot, whether or not the language fills it generously. The table is a description of the sound system, and the vocabulary distributes itself across it unevenly.

The letter behaves ordinarily on the page. It takes the full range of vowel marks, enters conjuncts, and carries the inherent short a like every other consonant sign, so standing alone it is read cha rather than ch. In the recitation of the table it is named immediately after its partner, and a learner who has the rule of the class can supply it without having seen it.

Its low frequency makes it one of the letters most likely to be miscopied in a tradition where scribes reproduce shapes rather than read words, because a hand that has written a character only a few times has no fluency to fall back on. In the East Asian material, where a great deal of copying was done by people who could not read Sanskrit, the rare letters are correspondingly the least reliable witnesses.

The Chinese Buddhist canon is not only a collection of sutras and commentaries. It also carries the working apparatus that the translation effort produced, and part of that apparatus is a set of compendia about the Siddham script itself: tables of the letters, accounts of their sound values, explanations of how the vowel marks attach and how consonants combine, and lists of the conjunct shapes. They were compiled in China during the centuries when Sanskrit texts were arriving in quantity and monks needed to be able to handle the originals.

Those compendia are the channel through which the script reached Japan as a subject rather than as a curiosity. A Japanese monk studying shittan was in large part studying this Chinese literature, and the Japanese tradition of Siddham scholarship grew directly out of it, adding its own manuals, dictionaries and commentaries over the centuries that followed.

Their survival is a piece of good fortune with a plain cause. The Chinese canon was copied, catalogued, carved into blocks and reprinted repeatedly by institutions with the resources to do it, so material that was never popular survived because it was inside something that was. A great deal of what can now be said about how Siddham was read in East Asia rests on documents that were preserved as part of a set rather than for themselves.