Alexander Changes the Disposition of his Forces. Meantime when Alexander perceived that nearly all the Persian cavalry had changed their ground and gone to his left towards the sea, and that on his side only the Peloponnesians and the rest of the Grecian cavalry were posted there, he sent the Thessalian cavalry thither with speed, ordering them not to ride along before the front of the whole array, lest they should be seen by the enemy to be shifting their ground, but to proceed by stealth in the rear of the phalanx.249 In front of the cavalry on the right, he posted the lancers under the command of Protomachus, and the Paeonians under that of Aristo; and of the infantry, the archers under the direction of Antiochus, and the Agrianians under that of 98Attalus. Some of the cavalry and archers also he drew up so as to form an angle with the centre250 towards the mountain which was in the rear; so on the right his phalanx had been drawn up separated into two wings, the one fronting Darius and the main body of Persians beyond the river, and the other facing those who had been posted at the mountain in their rear. On the left wing the infantry consisting of the Cretan archers and the Thracians under command............