His attendants followed. The troops around him, the best in the army, gave way. Soon the field was dense with fugitives. So thick was the cloud of dust raised by the flying multitude that nothing could be seen. Amid the darkness were heard a wild clamor of voices and the noise of the whips of the charioteers as they urged their horses to speed. The cloud of dust alone saved Darius from capture by the pursuing horsemen. The left of the Persian army fought bravely, but at length it too gave way. Everything was captured,--camp, treasure, the king's equipage, everything but the king himself. How many were killed and taken is not known, but the army, as an army, ceased to exist. As at Issus, so at Arbela, it was so miserably managed that three-fourths of it had nothing whatever to do with the battle. Its dispersal ended the Persian resistance; the empire was surrendered to Alexander almost without another blow. Great a soldier as Alexander unquestionably was, he was remarkably favored by fortune, and won the greatest empire the world had up to that time known with hardly an effort, and with less loss of men than often takes place in a single battle. The treasure gained was immense. Darius seemed to have been heaping up wealth for his conqueror. Babylon and Susa, the two great capitals of the Persian empire, contained vast accumulations of money, part of which was used to enrich the soldiers of the victorious army. At Persepolis, the capital of ancient Persia, a still greater treasure was found, amounting to one hundred and twenty thousand talents in gold and silver, or about one hundred and twenty-five million dollars. It took five thousand camels and a host of mules to transport the treasure away. The cruel conqueror rewarded the Persians for this immense gift, kept through generations for his hands, by burning the city and slaughtering its inhabitants, in revenge, as he declared, for the harm which Xerxes had done to Greece a century and a half before. What followed must be told in a few words. The conqueror did not feel that his work was finished while Darius remained free. The dethroned king was flying eastward to Bactria. Alexander pursued him with such speed that many of his men and animals fell dead on the road. He overtook him at last, but did not capture him, as the companions of the Persian king killed him and left only his dead body to the victor's hands. For years afterwards Alexander was occupied in war, subduing the eastern part of the empire, and marching into India, where he conquered all before him. War, incessant war, was all he cared for. No tribe or nation he met was able to stand against his army. In all his career he never met a reverse in the field. He was as daring as Darius had been cowardly, exposed his life freely, and was more than once seriously wounded, but recovered quickly from his hurts.