Augustus and his immediate successors had hoped that this broad waterway would serve as an impassable barrier, but subsequent events showed that they were mistaken. Neither the Danube, nor the Rhine, nor the _Limes Romanus_--a high stone wall connecting these two rivers--which had been constructed by the Emperor Probus, nor other defenses of the empire, which had been developed by his successors, were adequate to prevent the ever increasing incursions of the barbarians into Roman territory. Among them, besides the Marcomanni and the Quadi, whose warlike activities engaged the attention of Marcus Aurelius during his stay in Carnuntum and Vindobona--Vienna--were the Suevi, the Gepidæ, the Alemanni, the Vindelici, the Heruli, and other peoples of Celtic and Germanic stock. These were followed by Slavs, by the Avars, the Goths, the Huns, the Alani, the Vandals, the Langobardi, who in ever increasing numbers crossed the Danube and laid waste to lands far distant from their original homes, until eventually their impetuous hosts had swept the vast region from the Baltic Sea to the desert of Sahara, from the Caucasus to the Pillars of Hercules, and until Alaric “secretly aspired to plant the Gothic standard on the walls of Rome and to enrich his army with the accumulated spoils of a hundred triumphs.” Gliding down the tortuous Danube past picturesque towns and villages and through delightful woodlands and sun-kissed vineyards our steamer soon carries us over the short distance which intervenes between Carnuntum and loyal old Pozsony--the capital of Hungary before it was transferred to Budapest. In this cosmopolitan city of historic and traditional lore an incident is recalled which puts in strong relief the bravery and chivalrous character of the Hungarians and shows how quick they are to act when a strong appeal is made to their loyalty and patriotism. Queen Maria Theresa, finding herself threatened by enemies on all sides, convened the estates of the realm in the throne room of the castle of Pozsony. Here the fair young sovereign, with the crown of St. Stephen on her head and an infant son in her arms, delivered in Latin this brief but stirring address: