Alexander then returned to the river Oxus, with the intention of advancing into Sogdiana, because news was brought that many of the Sogdianians had fled for refuge into their strongholds and refused to submit to the viceroy whom he had placed over them. While he was encamping near the river Oxus, a spring of water and near it another of oil rose from the ground not far from Alexander’s own tent. When this prodigy was announced to Ptolemy, son of Lagus, the confidential body-guard, he told Alexander, who offered the sacrifices which the prophets directed on account of the phenomenon. Aristander affirmed that the spring of oil was the sign of labours; but it also signified that after the labours there would be victory. CHAPTER XVI. SUBJUGATION OF SOGDIANA.—REVOLT OF SPITAMENES. He therefore crossed the river with a part of his army and entered Sogdiana, leaving Polysperchon, Attalus, Gorgias, and Meleager there among the Bactrians, with instructions to guard the land, to prevent the barbarians of that region from making any revolutionary change, and to reduce those who had already rebelled. He divided the army which he had with him into five parts; the first of which he put under the command of Hephaestion, the second under that of Ptolemy, son of Lagus, the confidential body-guard; over the third he put Perdiccas; Coenus and Artabazus commanded the fourth brigade for him, while he himself took the fifth division and penetrated into the land towards Maracanda.[573] The others also advanced as each found it practicable, reducing by force some of those who had fled for refuge into the strongholds, and capturing others who surrendered to them on terms of capitulation. When all his forces reached Maracanda, after traversing the greater part of the land of the Sogdianians, he sent Hephaestion away to plant colonies in the cities of Sogdiana. He also sent Coenus and Artabazus into Scythia, because he was informed that Spitamenes had fled for refuge thither; but he himself with the rest of his army traversed Sogdiana and easily reduced all the places still held by the rebels.