The Turks originally applied the name Iron Gates (Demir Kapou) to the rapids just below Drenkova as well as to those near Orsova, calling them respectively Upper and Lower Iron Gates. The name, which signified obstructions to navigation rather than natural gateways in the mountains, is now commonly applied to the lower rapids only, and the traveller who has passed through the Kasan defile usually expects to find a still more wonderful gorge at the Iron Gates below. He is sure to be disappointed, for the Iron Gates are only a series of dangerous rapids at the point where the river broadens out after leaving the mountains, and the scenery there is, by comparison with that of the Kasan defile, tame and uninteresting. With the Carpathian ends the series of remarkable gorges and defiles which has marked the course of the river at intervals from its source down, for the vast plain of Roumania extends from the foot-hills here to the shores of the Black Sea. The Iron Gates have been since earliest history of great military and political importance, forming as they do a natural barrier on the great water-way between the East and the West. According to Strabo, the Danube ended here and the Ister began, for the lower river was known to the Greeks as the Ιστρος. There is no record of any mention of the upper Danube before the first century B.C., when it was discovered by the Roman armies under Cæsar, who probably gave it the name Danubius. Max Müller, in his study of the origin of the name of the Danube, says that the Latin name is probably a translation of the Aryan word _danu_, which, in the védas, means moist, or an adaptation of the old Persian word of the same spelling which means a river. It is scarcely necessary to add that the river has now a different name in several of the countries through which it flows. The Germans call it the Donau, the Hungarians the Duna, the Roumanians the Dunari, and the Servians, Bulgarians, and Russians the Dunai. The Iron Gates marks in the history of our trip the loss of the Admiral of the fleet who, having exhausted all the time at his disposal, was obliged to leave us here, to the regret of all of us and his own intense disappointment.