For ten days the two armies remained in position without moving. The soothsayers on both sides reported that the sacrifices portended success to a policy of defence; disaster, if an attack should be attempted. It was to the Greek cause that the delay was more perilous. The army suffered greatly from the incessant attacks of the Persian cavalry; the scanty water supply was a great inconvenience and even a danger; and when, at the suggestion of his Theban friends, Mardonius sent his cavalry to cut off the supplies that were sent by the passes of Cithæron into the Greek camp, the dangers of the situation were still further aggravated. But the most serious peril of all was of another kind. The spirit of party, without which no free state can exist, but by which every free state is ultimately ruined, was rife in the Greek ranks. The traitors who had shown the signal of the shield after Marathon were not absent from the ranks at Platæa. The Thebans, with malignant sagacity, suggested to Mardonius that he should rely on the influences that were working for him, and avoid a general engagement. Happily for Greece, he refused their advice, which was discreditable, he said, to Persian honour. A people so superior in war had no need to resort to such expedients. He resolved to assume the offensive. The Greeks were apprised of this change of plan by a visitor from the Persian camp. After nightfall, Alexander, King of Macedonia, who claimed to be descended from the great hero Achilles, rode up to the Athenian outposts and demanded speech with the generals. They were fetched by the guard, and he told them that Mardonius had tried in vain to obtain from the sacrifices signs that promised success, but that, nevertheless, he was determined to attack. "Be prepared," he went on, "and if you prevail, do something for my freedom; I have risked my life for love of Greece, to save you from a surprise by the barbarians. I am Alexander of Macedon." When Pausanias heard the news he made a proposition to the Athenian generals, which, as coming from a Spartan, a race so punctilious in military honour, sounds very strange. He suggested that they should take the place of the Spartans on the right wing, where they would be opposed to the Persian infantry whom they had already conquered at Marathon, but whom the Spartans had never met in battle. The Athenians promptly agreed, but the movement was detected by Mardonius, and was met by a corresponding change in his line. On perceiving this, Pausanias reverted to the former arrangement. The first offensive movement on the part of Mardonius was eminently successful. His cavalry got past, or broke through the Spartan line, so as to get at the spring of Gargaphia. This they choked, and so deprived the Greek army of their only available water supply.