The oldest stone inscription featuring a numeral is the Tamil-Brahmi cave inscription from Tondur
How were numerals written in ancient times in the Tamil country, the land of Srinivasa Ramanujan, ‘The Man Who Knew Infinity'?
Literary sources in Tamil mention numbers only in words.
However, we do have ancient literary references specifically mentioning eN (‘numeral') as distinguished from ezhuttu (‘letter of the alphabet,' for example, Tolkappiyam 655.4, Tirukkural 392).
But as palm leaf manuscripts decay with time and hardly last for more than 200 years, we have to turn to durable stone or pottery inscriptions to know what the ancient Tamil numerals looked like. We illustrate two of them here, one from each class (Figs. 1 & 2).
The oldest stone inscription featuring a numeral is the Tamil-Brahmi cave inscription from Tondur, near Gingee, in Villupuram district, assigned to about the 3rd century C.E. (Fig. 1). The numeral 3 engraved at the end of a short two-line inscription in the cave is represented by three horizontal parallel lines.
The inscription records that the village of Agalur gifted three stone beds in the cave chiselled by Mosi.
The gift was made to the Jaina monks resident in the cave. The village still exists with the same name Agalur, near Tondur, both of which still have sizeable Jaina populations. The numeral 3 has the same form as in contemporary Prakrit inscriptions in the Brahmi script in North India.
A well-preserved pottery inscription from Alagankulam near Rameswaram has only the numeral incised in fairly large size (Fig. 2). The inscription is dated to the 1st or 2nd century C.E.
The number is read 408, from right to left, following the ancient convention of reading the digits from the right (ankaanaam vaamato gatih). The first digit at right looking like the cross is the symbol for 4.
It is followed by the symbol for 100 (resembling the Brahmi letter sa) and the last symbol at left is 8, incised in reversed direction.
As there is no accompanying text, we do not know the significance of the number. The find is still interesting for the absence of the place-value system. The convention of using symbols for 10, 100, and 1000 in expressing the higher numerals was current in Tamil Nadu until the advent of printing and the adoption of the international form of Indian numerals with place-value system.
The pottery inscription is also good evidence for widespread literacy, including numeracy, in the ancient Tamil country.