[373] Xenophon, Cyropæd. iii, 3, 26, about the πολυχειρία of the barbaric kings. In whatever manner the difficulties of approaching Babylon may have been overcome, the fact that they were overcome by Cyrus is certain. On first setting out for this conquest, he was about to cross the river Gyndês (one of the affluents from the East which joins the Tigris near the modern Bagdad, and along which lay the high road crossing the pass of Mount Zagros from Babylon to Ekbatana), when one of the sacred white horses, which accompanied him, insulted the river[374] so far as to march in and try to cross it by himself. The Gyndês resented this insult, and the horse was drowned: upon which Cyrus swore in his wrath that he would so break the strength of the river as that women in future should pass it without wetting their knees. Accordingly, he employed his entire army, during the whole summer season, in digging three hundred and sixty artificial channels to disseminate the unity of the stream. Such, according 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 Euphratês; and this river, which had been so laboriously trained to serve for protection, trade, and sustenance to the Babylonians, was now made the avenue of their ruin. Having left a detachment of his army at the two points where the Euphratês 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 off 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 decree 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 opportunity, 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,