A Mark That Outlived Its Parent Script

The independent letter for long i is one of the signs of Brahmi whose descent can be followed across the whole family. It is present in the Gupta-period hands, in the Siddham of the Buddhist manuscript tradition, in the northern Nagari line and in the southern branch that produced the Grantha, Tamil, Kannada, Telugu and Sinhala alphabets, and in the scripts that reached Southeast Asia with Indian religion and Indian administration. Every one of them keeps a separate sign for it, and every one of them keeps it in fourth place in the recited order.

That continuity is what makes the order itself an object of study rather than a convenience. The sequence of letters was learned by heart and recited, and recitation is conservative in a way that writing is not: shapes drift with the hand and the writing surface, but a position in a memorised list does not. The result is that two scripts whose letters look nothing alike still agree on which letter comes fourth, and a scholar can line them up position by position with no need to reconstruct the shapes at all. Comparing the shapes then becomes a separate question with an independent answer, which is the ordinary working method of Indian palaeography.