useless. The object of the chariots was to create unsteadiness in the ranks against which they were driven, and squadrons of cavalry followed close upon them to profit by such disorder. But the Asiatic chariots were rendered ineffective at Arbela by the light-armed troops, whom Alexander had specially appointed for the service, and who, wounding the horses and drivers with their missile weapons, and running alongside so as to cut the traces or seize the reins, marred the intended charge; and the few chariots that reached the phalanx, passed harmlessly through the intervals which the spearmen opened for them, and were easily captured in the rear.
A mass of the Asiatic cavalry was now, for the second time, collected against Alexander's extreme right, and moved round it, with the view of gaining the flank of his army. At the critical moment, when their own flanks were exposed by this evolution, Aretes dashed on the Persian squadrons with his horsemen from Alexander's second line. While Alexander thus met and baffled all the flanking attacks of the enemy, with troops brought up from his second line, he kept his own horseguards and the rest of the front line of his wing fresh, and ready to take advantage of the first opportunity for striking a decisive blow. This soon came. A large body of horse, who were posted on the Per-