Iravatham Mahadevan is a National Fellow of the Indian Council of Historical Research, and has been working on the Indus script for over 40 years. His publications include The Indus Script: Texts, Concordance and Tables (1977). A Tamil speaker, he has used historical linguistics and statistical studies to examine the Dravidian components in Vedic Sanskrit, and how these might point to interpretations of the Indus Valley script.
Dr. Gregory Possehl calls Mahadevan a "careful, methodical worker, taking care to spell out his assumptions and methods. . . 'Tentative conclusions' and 'working hypotheses' are more his style than set ideas and fait accompli" (Indus Age: The Writing System, p. 130).
The following paper by Mahadevan, An Encylopaedia of the Indus Script, is a review of Asko Parpola's Deciphering the Indus Script, and was published in the International Journal of Dravidian Linguistics (Trivandrum, Jan. 1997, reprinted by permission of the author). Mahadevan uses this opportunity to summarize and review the full breadth of Parpola's work, from evidence from the often misunderstood question of "Aryans" in the subcontinent to specific interpretations of various signs. An easily printed text-only version of the 14 sections that follow is also available.
There is also an ancient Indus script dictionary comparing Mahadevan's and Parpola's key seal sign interpretations.
Mahadevan's original article was not illustrated, except for drawings of Indus signs. The pages that follow include a number of images, mainly of sealings from Harappa, courtesy of the Harappa Archaeological Project (HARP).