CYRUS ATTACKS BABYLON. 213 hig to Herodotus, was the incident which postponed for one year the fall of the great Babylon ; but in the next spring Cyrus and his army were before the walls, after having defeated and driven in the population who came out to fight. But the walls were artificial mountains (three hundred feet high, seventy-five feet thick, and forming a square of fifteen miles to each side), within which the besieged defied attack, and even blockade, having previously stored up several years' provision. Through the midst of these walls, however, flowed the Euphrates ; and this river, which had been so laboriously trained to serve for pro- tection, trade, and sustenance to the Babylonians, was now made the avenue of their ruin. Having left a detachment of bis army at the two points where the Euphrates enters and quits the city, Cyrus retired with the remainder to the higher part of its course, where an ancient Babylonian queen had prepared one of the great lateral reservoirs for carrying oft' in case of need the superfluity of its water. Near this point Cyrus caused another reservoir and another canal of communication to be dug, by means of which he drew off the water of the Euphrates to such a degree that it became not above the height of a man's thigh. The period chosen was that of a great Babylonian festival, when the whole population were engaged in amusement and revelry ; and the Persian troops left near the town, watching their oppor- tunity, entered from both sides along the bed of the river, and took it by surprise with scarcely any resistance. At no other time, except during a festival, could they have done this, says Herodotus, had the river been ever so low; for both banks throughout the whole length of the town were provided with quays, with continuous walls, and with gates at the end of every street which led down to the river at right angles : so that if the population had not been disqualified by the influences of the moment, they would have caught the assailants in the bed of the river " as a trap," and overwhelmed them from the walls along- side. Within a square of fifteen miles to each side, we are not surprised to hear that both the extremities were already in the power of the besiegers before the central population heard of it, and while they were yet absorbed in unconscious festivity. 1 1 Herodot. i, 191 This latter poition of the story, if we may judge from
