Description of the Euphrates and the Pallacopas. While the triremes were being built for him, and the harbour near Babylon was being excavated, Alexander sailed from Babylon down the Euphrates to what was called the river Pallacopas, which is distant from Babylon about 800 stades.947 This Pallacopas is not a river rising from springs, but a canal cut from the Euphrates. For that river flowing from the Armenian mountains,948 proceeds within its banks in the season of winter, because its water is scanty; but when the spring begins to make its appearance, and especially just before the summer solstice, it pours along with mighty stream and overflows its banks into the Assyrian country.949 For at that season the snow upon the Armenian mountains melts and swells its water to a great degree; and as its stream flows high above the level of the country, it would flow over the land if some one had not furnished it with an outlet along the Pallacopas and turned it aside into the marshes and pools, which, beginning from this canal, extend as far as the country contiguous to Arabia. Thence it spreads out far and wide into a shallow lake, from which it falls into the sea by many invisible mouths. After the snow has melted, about the time of the setting of the Pleiades, the Euphrates flows with a small stream; but none the less the greater part of it discharges itself into the pools along the Pallacopas. Unless, therefore, some one 412had dammed up the Pallacopas again, so that the water might be t............