The Life of Apollonius of Tyana, by Philostratus, tr. F.C. Conybeare, , at sacred-texts.com
SO they remained the next day as well, for Indian would not let them go, and he gave them a letter for Iarchas, written in the following terms:—
p. 226 p. 227
"King Phroates to Iarchas his master and to his companions, all hail!
Apollonius, wisest of men, yet accounts you still wiser than himself, and is come to learn your lore. Send him away therefore when he knows all that you know yourselves, assured that nothing of your teachings will perish, for in discourse and memory he excels all men. And let him also see the throne, on which I sat, when you, Father Iarchas, bestowed on me the kingdom. And his followers too deserve commendation for their devotion to such a master. Farewell to yourself and your companions."
AND they rode out of Taxila, and after a journey of two days reached the plain, in which Porus is said to have engaged Alexander: and they say they saw gates therein that enclosed nothing, but had been erected to carry trophies. For there was set up on them a statue of Alexander standing in a four-poled chariot, 1 as he looked when at Issus he confronted the satraps of Darius. And at a short distance from one another there are said to have been built two gates, carrying the one a statue of Porus, and the other one of Alexander, of both, as I imagine, reconciled to one another after the battle; for the one is in the attitude of one man greeting another, and the other of one doing homage.
p. 228 p. 229
AND having crossed the river Hydraotes and passed by several tribes, they reached the Hyphasis, and thirty stades away from this they came on altars bearing this inscription: "To Father Ammon and Heracles his brother, and to Athena Providence and to Zeus of Olympus and to the Cabeiri of Samothrace and to the Indian Sun and to the Delphian Apollo."
And they say there was also a brass column dedicated, and inscribed as follows:
"Alexander stayed his steps at this point." The altars we may suppose to be due to Alexander who so honored the limit of his Empire; but I fancy the Indians beyond the Hyphasis erected the column, by way of expressing their pride at Alexander's having gone no further.
1:227:1 i.e. with eight horses.