Mongolian Cha ᠴ

Cha writes the voiceless palatal affricate, the sound English spells ch in church, and it is the twentieth letter of the alphabet. It is native, common and distinctly written, and with the voiced affricate that follows it it forms a pair on the same model as the sibilants and the stops. Unicode encodes cha at U+1834. The affricates entered Mongolian's ancestry from a letter that had originally written something else, which is the ordinary history of a borrowed alphabet: as a script passes from language to language, letters are reassigned to whatever the new language needs a sign for, and the sound a letter writes today may have little to do with the sound it was invented for.

The Aramaic abjad from which this script ultimately descends had no palatal affricate, and the sign that ended up carrying it in Mongolian did other work in earlier stages. A reader tracing correspondences between Mongolian and its Semitic ancestors should therefore expect the vowels and the plain consonants to line up cleanly and expect the affricates to be where the alignment breaks down. The letter is common in native vocabulary and also frequent in Tibetan loanwords, where it renders more than one source sound.

Traditional Mongolian is written in vertical columns that advance from left to right across the page, and that combination is close to unique. Chinese, Japanese and Korean have all been written vertically, but their columns advance from right to left. Mongolian goes the other way, and the reason is inheritance. Its ancestor was written horizontally from right to left, in the manner of the Aramaic family, and was turned a quarter turn counterclockwise to run down the page. Rotate a right to left line that way and its lines, which formerly ran down the page, now run across it to the right. The script therefore carries a record of its own reorientation in the one feature everybody notices first.

Why the rotation happened at all is usually explained by contact with Chinese vertical writing, a plausible account that places the change among the Uyghurs rather than the Mongols. The consequences are practical and continuing. Mongolian sits badly in horizontal layouts, needs special handling in web pages and word processors, and produces bilingual signs in Inner Mongolia in which the Mongolian runs down and the Chinese runs across, sharing a surface without sharing an axis. Book design inherits the same problem: a Mongolian volume opens and paginates on its own logic, and pairing it with a horizontally set language in one binding forces a choice that neither tradition makes on its own.