This section is from the book "Some Contributions Of South India To Indian Culture", by S. Krishnaswami Aiyangar. Also available from Amazon: Some Contributions of South India to Indian Culture.
The famous Hathigumpha inscription of Kharavela which has been recently read and re-read and published by Mr. K. P. Jayaswal in the Bihar and Orissa Research Society's Journal, and the controversy over which is not yet unfortunately over, has one detail which seems clearly to refer to the sending of tribute or presents in the shape of elephants and valuable jewels from the Pandya country. These presents were sent over-sea. In itself, communication over-sea with Kalinga is quite possible, and that raises actually no difficulty; and if presents did come from there it must be of the character described. If the reading of the inscription in regard to that particular part is put beyond a doubt, that would establish communication between Kalinga and the south. In the period following, the great Chola Kari-kala went north as was pointed out already and received in his turn presents from the kings of Vajra, Magadha and Malva or Avanti. The existence of a country like Vajra in the valley of the Sone is brought to our notice only in this connection. And that possibility finds confirmation in another reference in the same Hathigumpha inscription where Khara-vela is said to have married a princess of the Vajra royal family. This reference seems to give the character of historicity to the references contained in Tamil literature, in a connection to which captious objections, may, it is just possible, be raised. This inscriptional reference to a geographical detail like that puts the character of the literary reference on a somewhat better footing. We shall have to revert to this point later.