The History Of Herodotus Volume 2 of 2
Page: 21449. The herald having thus spoken waited for some time, and then, as no one made him any answer, he departed and went back; and having returned he signified to Mardonios that which had happened to him. Mardonios then being greatly rejoiced and elated by his empty 53 victory, sent the cavalry to attack the Hellenes: and when the horsemen had ridden to attack them, they did damage to the whole army of the Hellenes by hurling javelins against them and shooting with bows, being mounted archers and hard therefore to fight against: and they disturbed and choked up the spring Gargaphia, from which the whole army of the Hellenes was drawing its water. Now the Lacedemonians alone were posted near this spring, and it was at some distance from the rest of the Hellenes, according as they chanced to be posted, while the Asopos was near at hand; but when they were kept away from the Asopos, then they used to go backwards and forwards to this spring; for they were not permitted by the horsemen and archers to fetch water from the river..
50. Such then being the condition of things, the generals of the Hellenes, since the army had been cut off from its water and was being harassed by the cavalry, assembled to consult about these and other things, coming to Pausanias upon the right wing: for other things too troubled them yet more than these of which we have spoken, since they no longer had provisions, and their attendants who had been sent to Peloponnese for the purpose of getting them had been cut off by the cavalry and were not able to reach the camp..
51. It was resolved then by the generals in council with one another, that if the Persians put off the battle for that day, they would go to the Island. This is distant ten furlongs 54 from the Asopos and the spring Gargaphia, where they were then encamped, and is in front of the city of the Plataians: and if it be asked how there can be an island on the mainland, thus it is 55:—the river parts in two above, as it flows from Kithairon down to the plain, keeping a distance of about three furlongs between its streams, and after that it joins again in one stream; and the name of it is Oëroe, said by the natives of the country to be the daughter of Asopos. To this place of which I speak they determined to remove, in order that they might be able to get an abundant supply of water and that the cavalry might not do them damage, as now when they were right opposite. And they proposed to remove when the second watch of the night should have come, so that the Persians might not see them set forth and harass them with the cavalry pursuing. They proposed also, after they had arrived at this place, round which, as I say, Oëroe the daughter of Asopos flows, parting into two streams 56 as she runs from Kithairon, to send half the army to Kithairon during this same night, in order to take up their attendants who had gone to get the supplies of provisions; for these were cut off from them in Kithairon.