surrendered themselves. After waiting four days in the camp, he took up those who had been left behind on the march, all of them advancing in safety except the Agrianians, who, while guarding the rear, were attacked by the barbarian mountaineers. But these soon drew off when they got the worst of it in the skirmish. Starting from this place, he advanced into Hyrcania as far as Zadracarta, the capital of the Hyrcanians. In this place[475] he was rejoined by Craterus, who had not succeeded in falling in with the Grecian mercenaries of Darius; but he had thoroughly traversed the whole country, gaining over part of it by force and the other part by the voluntary capitulation of the inhabitants. Erigyius also arrived here with the baggage and waggons; and soon after Artabazus[476] came to Alexander with three of his sons, Cophen, Ariobarzanes, and Arsames, accompanied by Autophradates, viceroy of Tapuria, and envoys from the Grecian mercenaries in the service of Darius. To Autophradates he restored his viceregal office; but Artabazus and his sons he kept near himself in a position of honour, both on account of their fidelity to Darius and because they were among the first nobles of Persia. To the envoys from the Greeks, begging him to make a truce with them on behalf of the whole mercenary force, he replied that he would not make any agreement with them; because they were acting with great guilt in serving as soldiers on the side of the barbarians against Greece, in contravention of the resolution of the Greeks. He commanded them to come in a body and surrender, leaving it to him to treat them as he pleased, or to preserve themselves as best they could. The envoys said that they yielded both themselves and their comrades to Alexander, and urged him to send some one with them to act as their leader, so that they might be conducted to him with safety. They said they were 1,500 in number. Accordingly he sent Andronicus, son of Agerrhus, and Artabazus to them. CHAPTER XXIV. EXPEDITION AGAINST THE MARDIANS.