The proffered alliance of the Olynthians was thus rejected, as the entreaty of the Amphipolitans for aid had previously been. Athens had good reason to repent of both. The secret negotiation brought her no nearer to the possession of Amphipolis. It ended in nothing, or in worse than nothing, as it amused her with delusive expectations, while Philip opened a treaty with the Olynthians, irritated, of course, by their recent repulse at Athens. As yet he had maintained pacific relations with the Athenians, even while holding Amphipolis contrary to his engagement. But he now altered his policy, and contracted alliance with the Olynthians; whose friendship he purchased not only by ceding to them the district of Anthemus (lying between Olynthus and Therma, and disputed by the Olynthians with former Macedonian kings), but also by conquering and handing over to them the important Athenian possession of Potidæa.[492] We know no particulars of these important transactions. Our scanty authorities merely inform us, that during the first two years (358-356 B. C.), while Athens was absorbed by her disastrous Social War, Philip began to act as her avowed enemy. He conquered from her not only Pydna and other places for himself, but also Potidæa for the Olynthians. We are told that Pydna was betrayed to Philip by a party of traitors in the town;[493] and he probably availed himself of the secret propositions made by Athens respecting the exchange of Pydna for Amphipolis, to exasperate the Pydnæans against her bad faith; since they would have good ground for resenting the project of transferring them underhand, contrary to their own inclination. Pydna was the first place besieged and captured. Several of its inhabitants, on the ground of prior offence towards Macedonia,[494] are said to have been slain, while even those who had betrayed the town were contemptuously treated. The siege lasted long enough to transmit news to Athens, and to receive aid, had the Athenians acted with proper celerity in despatching forces. But either the pressure of the Social War—or the impatience of personal service as well as of pecuniary payment—or both causes operating together—made them behindhand with the exigency. Several Athenian citizens were taken in Pydna and sold into slavery, some being ransomed by Demosthenes out of his own funds; yet we cannot make out clearly that any relief at all was sent from Athens.[495] If any was sent, it came too late. [492] Demosthenes, Philipp. ii. p. 71. s. 22. [493] Demosthen. adv. Leptinem, p. 476. s. 71. ... φέρε δὴ κἀκεῖνο ἐξετάσωμεν, οἱ προδόντες τὴν Πύδναν καὶ τἄλλα χωρία τῷ Φιλίππῳ τῷ ποτ᾽ ἐπαρθέντες ὑμᾶς ἠδίκουν; ἢ πᾶσι πρόδηλον τοῦτο, ὅτι ταῖς παρ᾽ ἐκείνου δωρειαῖς, ἃς διὰ ταῦτα ἔσεσθαι σφίσιν ἡγοῦντο; Compare Olynthiac i. p. 10. s. 5. This discourse was pronounced in 355 B. C., thus affording confirmatory evidence of the date assigned to the surrender of Pydna and Potidæa.