History of the Peloponnesian War
Thucydides
Thucydides, Vol. 1-4. Smith, Charles Foster, translator. London and Cambridge, MA: Heinemann and Harvard University Press, 1919-1923.
And touching first at Scione, which was still under siege, and taking on from there some hoplites of the garrison, he then sailed down to the port of Cophus, which is not far distant from the city of Torone.
From there, on learning from deserters that Brasidas was not in Torone and that the inhabitants were not a match for him in battle, he advanced with his land-force against the city, but sent ten ships to sail round into the harbour.
And first he arrived at the new wall which Brasidas had built round the city for the purpose of taking in the suburb, having pulled down a part of the old wall and made one city of Torone.
But Pasitelidas, the Lacedaemonian commander, and the garrison that was present came to the defence of this wall and tried to ward off the Athenian assault. But they were hard pressed and the ships that had been sent round were now sailing into the harbour; so Pasitelidas, in fear that the ships might take the town, undefended as it was, before he could get there, and that if the new fortifications were carried he might be captured in them, left them and hurried back into the town.