Page:General History of Europe 1921.djvu/224

158 General History of Europe 249. Protection of the Empire. We have seen that on the north and east the Roman Empire was open to attack. Owing to the pressure of the German barbarians, civilization was constantly in danger. Vespasian and his sons did much to make the northern boundary safe by building walls and fortifications along the THE EMPEROR TRAJAN SACRIFICING AT HIS NEW BRIDGE In the background we see the heavy stone piers of the bridge, supporting the wooden upper structure, built with strong railings. In the foreground is the altar, toward which the emperor advances from the right, with a flat dish in his right hand, from which he is pouring a libation. At the left of the altar stands a priest, naked to the waist and leading an ox to be slain for the sacrifice. A group of the emperor's officers approach from the left, bearing army standards. The scene is sculptured with many others on the column of Trajan at Rome, and is one of the best examples of Roman relief sculpture of the second century frontier. But on the lower Danube they were unable to crush the growing power of the Dacians (see map, p. 160). 250. Trajan (A.D. 98-nv) and his Wars. This left the whole threatening situation on the lower Danube to be met by the bril- liant soldier Trajan. He captured one stronghold of the Dacians after another, and finally destroyed their capital. Having built a massive bridge across the Danube, Trajan made Dacia a Roman