The Eight Books of Thucydides' History, translated by R. Crawley.
"The long speech of the Athenians I do not pretend to understand. They said a good deal in praise of themselves, but nowhere denied that they are injuring our allies and Peloponnese. And yet if they behaved well against the Mede then, but ill towards us now, they deserve double punishment for having ceased to be good and for having become bad. We meanwhile are the same then and now, and shall not, if we are wise, disregard the wrongs of our allies, or put off till to-morrow the duty of assisting those who must suffer to-day. Others have much money and ships and horses, but we have good allies whom we must not give up to the Athenians, nor by lawsuits and words decide the matter, as it is anything but in word that we are harmed, but render instant and powerful help. And let us not be told that it is fitting for us to deliberate under injustice; long deliberation is rather fitting for those who have injustice in contemplation. Vote therefore, Lacedaemonians, for war, as the honour of Sparta demands, and neither allow the further aggrandizement of Athens, nor betray our allies to ruin, but with the gods let us advance against the aggressors."
With these words he, as ephor, himself put the question to the assembly of the Lacedaemonians. He said that he could not determine which was the loudest acclamation (their mode of decision is by acclamation not by voting); the fact being that he wished to make them declare their opinion openly and thus to increase their ardour for war. Accordingly he said: "All Lacedaemonians who are of opinion that the treaty has been broken, and that Athens is guilty, leave your seats and go there," pointing out a certain place; "all who are of the opposite opinion, there." They accordingly stood up and divided; and those who held that the treaty had been broken were in a decided majority. Summoning the allies, they told them that their opinion was that Athens had been guilty of injustice, but that they wished to convoke all the allies and put it to the vote; in order that they might make war, if they decided to do so, on a common resolution. Having thus gained their point, the delegates returned home at once; the Athenian envoys a little later, when they had dispatched the objects of their mission. This decision of the assembly, judging that the treaty had been broken, was made in the fourteenth year of the thirty years' truce, which was entered into after the affair of Euboea.
The Lacedaemonians voted that the treaty had been broken, and that the war must be declared, not so much because they were persuaded by the arguments of the allies, as because they feared the growth of the power of the Athenians, seeing most of Hellas already subject to them.
Reference address : https://www.ellopos.net/elpenor/greek-texts/ancient-greece/thucydides/history-1.asp?pg=43