could at any moment, if watchful, bring the bridge to their own side of the river, and then secure it with all their ships till Darius should appear on the farther shore. But the Scythians send Scopasis with his army. He tells the Ionians that he knew that Darius had ordered them to wait sixty days; they were to wait till the time had passed and then sail away. When the Greeks had undertaken to do this Scopasis marches with his army to the north. He joins Idanthyrsus again when Darius has begun his retreat. The united army reaches the bridge long before Darius. A second time we have negotiations with the Ionians. The sixty days are past, and the Scythians entreat the Ionians to sail away now, at any rate. They are satisfied when the Greeks remove a part of the bridge, saying that they have begun to break it up and will now sail home. They do not wait till they see all the ships sailing down the stream. They have cut off Darius; he cannot escape them and reach the Danube. But they turn back into the steppe, and miss him again. Still more unintelligible and extraordinary is the conduct of Darius. When the Danube has been crossed he commands the Greeks to break down the bridge; the crews are to join the army on land. It would follow from this that Darius thought the bridge no longer necessary. It was not his intention therefore to return to the Danube, but to march round the Black Sea, and over the Caucasus, if indeed he did not mean to skirt the northern shore of the Caspian and return home over the Oxus. If this was his object why did he not avail himself of the important assistance which the fleet could afford him, and command it to accompany the march of the army along the northern shore of the Black Sea? It would then have brought provisions to the army, or to the mouths of the rivers, and supported any attacks on the Greek cities of these coasts; on Tyras at the mouth of the Dniester, on Ordessus on the Teligul, on Olbia at the mouth of the Bug, and Panticapaeum on the Cimmerian Bosphorus. To leave the attack on the Greek cities to the Greek ships only would be dangerous, but there was no danger in giving them a share in it if the main point was to strengthen the army on land. But Darius wished neither to use the fleet, nor to allow the bridge to stand, which is the more remarkable as the bridges on the Bosphorus were not removed but allowed to remain, obviously under the protection of Greek men-of-war. At the Danube Darius has to be informed for the first time by a Greek that a way must be left open for his return. Nevertheless he does not order the Greeks to keep the bridge till further notice, or till his return. For sixty days only after his departure does he leave the means for his return open; so long the bridge is to remain; when that time has expired, the fleet is to sail away. What interest had Darius in allowing the Greeks to depart home as quickly as possible? In order to fix this