What Comes After the End

Because this letter closes the received order, everything an alphabet adds is placed after it, and what a given script has in that position is a compact statement of which languages it was made to serve. Brahmi itself puts the retroflex lateral there, a sound classical Sanskrit does not treat as separate but Vedic recitation keeps and several Middle Indo-Aryan dialects use. Tamil-Brahmi puts three further consonants after that, for Dravidian sounds no Indo-Aryan text needs. Several traditions add the cluster of the retroflex sibilant with the velar stop, recited as though it were a letter.

The convention of adding at the end rather than inserting in place is not a matter of tidiness. The order was a memorised sequence recited whole, and inserting a letter in the middle would have obliged every reciter to relearn the list, whereas an addition at the end leaves the sequence intact and adds one item. The same instinct produced the dotted letters of the later northern scripts, which file a new sound under the existing letter it resembles rather than claiming a position of its own.

So the tail of an Indic alphabet is where its history is written. The letters before the aspirate are inherited; the letters after it are what a particular script and a particular language needed and went and got.