[191] Xenoph. Hellen. i, 3, 5-7; Diodor. xiii, 66. The blockade of the town was now made so sure, that Alkibiadês departed with a portion of the army to levy money and get together forces for the siege of Byzantium afterwards. During his absence, Theramenês and Thrasybulus came to terms with Pharnabazus for the capitulation of Chalkêdon. It was agreed that the town should again become a tributary dependency of Athens, on the same rate of tribute as before the revolt, and that the arrears during the subsequent period should be paid up. Moreover, Pharnabazus himself engaged to pay to the Athenians twenty talents on behalf of the town, and also to escort some Athenian envoys up to Susa, enabling them to submit propositions for accommodation to the Great King. Until those envoys should return, the Athenians covenanted to abstain from hostilities against the satrapy of Pharnabazus.[192] Oaths to this effect were mutually exchanged, after the return of Alkibiadês from his expedition. For Pharnabazus positively refused to complete the ratification with the other generals, until Alkibiadês should be there to ratify in person also; a proof at once of the great individual importance of the latter, and of his known facility in finding excuses to evade an agreement. Two envoys were accordingly sent by Pharnabazus to Chrysopolis, to receive the oaths of Alkibiadês, while two relatives of Alkibiadês came to Chalkêdon as witnesses to those of Pharnabazus. Over and above the common oath shared with his colleagues, Alkibiadês took a special covenant of personal friendship and hospitality with the satrap, and received from him the like. [192] Xenoph. Hellen. i, 3, 9. Ὑποτελεῖν τὸν φόρον Καλχηδονίους Ἀθηναίοις ὅσονπερ εἰώθεσαν, καὶ τὰ ὀφειλόμενα χρήματα ἀποδοῦναι· Ἀθηναίους δὲ μὴ πολεμεῖν ~Καλχηδονίοις~, ἕως ἂν οἱ παρὰ βασιλέα πρέσβεις ἔλθωσιν. This passage strengthens the doubts which I threw out in a former chapter, whether the Athenians ever did or could realize their project of commuting the tribute, imposed upon the dependent allies, for an _ad valorem_ duty of five per cent. on imports and exports, which project is mentioned by Thucydidês (vii, 28) as having been resolved upon at least, if not carried out, in the summer of 413 B.C. In the bargain here made with the Chalkêdonians, it seems implied that the payment of tribute was the last arrangement subsisting between Athens and Chalkêdon, at the time of the revolt of the latter. Next, I agree with the remark made by Schneider, in his note upon the passage, Ἀθηναίους δὲ μὴ πολεμεῖν ~Καλχηδονίοις~. He notices the tenor of the covenant as it stands in Plutarch, τὴν Φαρναβάζου δὲ χώραν μὴ ἀδικεῖν (Alkib. c. 31), which is certainly far more suitable to the circumstances. Instead of Καλχηδονίοις, he proposes to read Φαρναβάζῳ. At any rate, this is the meaning.