At length he returned to the bridge, where he found the preparations for the movement of the fleet and of the army nearly completed. He determined, before leaving the Asiatic shores, to erect a monument to commemorate his expedition, on the spot from which he was to take his final departure. He accordingly directed two columns of white marble to be reared, and inscriptions to be cut upon them, giving such particulars in respect to the expedition as it was desirable thus to preserve. These inscriptions contained his own name in very conspicuous characters as the leader of the enterprise; also an enumeration of the various nations that had contributed to form his army, with the numbers which each had furnished. There was a record of corresponding particulars, too, in respect to the fleet. The inscriptions were the same upon the two columns, except that upon the one it was written in the Assyrian tongue, which was the general language of the Persian empire, and upon the other in the Greek. Thus the two monuments were intended, the one for the Asiatic, and the other for the European world. At length the day of departure arrived. The fleet set sail, and the immense train of the army put itself in motion to cross the bridge.[H] The fleet went on through the Bosporus to the Euxine, and thence along the western coast of that sea till it reached the mouths of the Danube. The ships entered the river by one of the branches which form the delta of the stream, and ascended for two days. This carried them above the ramifications into which the river divides itself at its mouth, to a spot where the current was confined to a single channel, and where the banks were firm. Here they landed, and while one part of the force which they had brought were occupied in organizing guards and providing defenses to protect the ground, the remainder commenced the work of arranging the vessels of the fleet, side by side, across the stream, to form the bridge. [Footnote H: See Frontispiece.]