Avestan Sshe 𐬴

This is the fourth of the alphabet's sh type signs, transliterated with a dot beneath, and the manuscripts keep it apart from the other three. Four separate letters for sounds that most writing systems gather under one is the clearest single measure of how finely this alphabet cuts. The sibilants close the consonant section before the final letter, and they are the largest family in the alphabet: six signs, where the scripts around it managed with two or three. The group runs from the plain s and z through the sh sounds, of which there are four. It stands fifty-third in the alphabet as a whole and thirty-seventh of the thirty-eight consonants, between Avestan Shye and Avestan He. That position is not arbitrary.

The sequence follows a scheme, vowels before consonants and consonants by place of articulation, and each letter's place in it is a statement about the sound. The tradition calls the script din dabireh, the religion writing. It served the Avesta and very little else, and the shape of its letter list follows the sounds of that one language rather than any general requirement of writing in Sasanian Iran. Avestan is written from right to left, a direction inherited along with the letterforms. What was not inherited is the practice of writing every vowel, and that single departure is what makes the script legible to somebody who does not already know the word in front of them.

Four separate letters for the sh region of the sound system is a larger provision than any script of the period made, and it is the fact most often cited when the Avestan alphabet is called phonetically exact. The distinctions come from the recitation, not from the scribes. A script made in the Sasanian period for a text composed a thousand years and more earlier is an act of preservation rather than of composition. Nothing was being written down for the first time. What was being done was the fixing, in a form that would not drift, of something priests already held in memory. The script was put to a second use as well.

Pazand is Middle Persian written in Avestan letters, taken up precisely because those letters record vowels and the Pahlavi ones did not, and it is the clearest practical demonstration of what the alphabet was good for. In the digital record the letter is encoded at U+10B34 AVESTAN LETTER SSHE. The Avestan block sits wholly in the supplementary planes, and every letter in it takes four bytes in the encoding most of the web runs on. That is the practical reason Avestan text is still uncommon online, and why a page carrying it depends on the reader having a font that covers the range. Zoroastrianism is a living religion with a small community, and the Avesta is its liturgy rather than its archive. The letters of this alphabet are therefore not an antiquarian matter. They record sounds a priest is still expected to produce.