with unabated fury. It was not till almost every leader had fallen that the Persian cavalry gave way. Elsewhere in the field the victory was more easily won. The _élite_ of the Persian army had been brought together to oppose Alexander, and the remainder did not hold their ground with equal tenacity. When the phalanx had made its way across the river, and reformed itself again on the eastern bank, it encountered no opposition. There still remained, however, a force to be dealt with which, had it been properly handled, might have been found a serious difficulty for the conquerors. The infantry, as has been said, was posted in reserve, and of this force not less than a half, numbering as many as ten thousand, consisted of Greek mercenaries. These had remained in absolute inaction, idly watching the struggle on the level ground below. They had no responsible leaders; no orders had been issued to them. The Persian generals, confident in the strength of their special arm, the cavalry, neglected to make any use of this invaluable force. And yet they might have known what ten thousand Greeks, well led, could do! Alexander came up and charged the unprotected flank of the Greek force. "He had the defects of his virtues," and was too eager in "drinking the delight of battle." His charger--not the famous Bucephalus, which had fallen lame, but another horse--was killed under him. The light infantry also delivered an attack, but the mercenaries still held their ground. But when the phalanx came up, their strength or their courage failed. The front ranks were crushed by the advance of the ponderous machine, and the rest first wavered, then broke up in hopeless confusion. Not less than half of their number were killed in their places or in the attempt to escape. The rest were either admitted to quarter, or contrived to make their way to some place of safety. FOOTNOTES: [Footnote 13: Cambyses, in a fit of frantic jealousy--so the story ran--had put his brother Smerdis to death. Cambyses died in Egypt. The magi, Median soothsayers and priests, contrived that one of their number should personate the murdered prince. After he had occupied the Persian throne for a few months, seven nobles conspired against him and slew him. One of the seven, Darius, became king; the others were rewarded by perpetual immunity from taxes, for themselves and their descendants, and other privileges.] II THE IRRESISTIBLE PHALANX