But when day after day passed and still the other ambassadors did not come, the Spartans did not hide their suspicion that they were being deceived. When a rumour reached them that the Athenians had never ceased to build the wall, which was now nearly complete, they were angry indeed, and going to Themistocles they demanded that he should tell them the truth.
He still denied that the citizens had been building the wall in his absence, but if they doubted his word, he bade them send ambassadors to Athens, that they might see for themselves whether he was deceiving them or not.
So the Spartans sent ambassadors to Athens, and then Themistocles bade his colleagues join him, for he knew that now both he and they would be safe. The Spartan ambassadors would be hostages for their lives.
The first thing the Spartans saw as they approached Athens was a high, strong wall. Then they knew that they had been deceived, and they sent a messenger to tell their countrymen that Themistocles had played them false.
Themistocles was no coward. He went into the council and boldly told the Spartans that it was true he had deceived them, so that the walls of Athens might be built before they could interfere.
Indignant as the Spartans were and ashamed of their own folly in being deceived by the crafty Athenian, they dared not harm the ambassadors lest their own messengers should not return in safety.
So they sent them away, and Themistocles and his fellows returned in triumph to Athens.
Soon after this the city wall was finished, and Themistocles then urged the people to build another great wall round the Piraeus. When this was done, Athens had the largest and safest harbour in Greece.
The other states now appointed her to be the head of the allied fleet, and no one was more proud of this than Themistocles. For it was he who had first persuaded the Athenians to make themselves into a great sea-power.