A Place in the Table With Nothing in It

The long syllabic l is the one letter in the Brahmi vowel series with no word in the language behind it. Sanskrit does not use the sound. It appears in the grammatical literature in artificial forms constructed to complete a paradigm, and Whitney's grammar says as much plainly: the vowel occurs only in the grammarians' own made examples. The letter exists because the vowels are organised in short and long pairs, and the tradition preferred a table complete in its pattern to a table with an honest gap in it.

Stated that way it sounds like a flaw, and it is worth resisting that reading. The table is a piece of analysis before it is a list of signs, and the analysis is that Indian phonetics classified sounds by independent features rather than as a list of individual items. Place, quantity and manner are treated as varying independently, and a system built that way generates cells that the language happens not to fill, in the same way that a well-made chemical table has boxes waiting for elements nobody has yet made. The tradition kept the empty cell and marked it rather than quietly closing the table around it, which is the more informative choice and the one a modern reader can still learn from.