Numerous representations of forts, boats, different kinds of troops, skirmishes, and sieges follow, ending with the surrender of Decebalus and the return of Trajan to Rome, where a great festival is celebrated. The arrival at Rome, and the crowd of Romans going to meet the great conqueror, are very vividly drawn. An immense number of bulls for sacrifice, altars, camilli, and half-naked popæ are introduced into the triumphal rejoicings, and the first campaign ends with the figure of Trajan offering incense on the altar of Jupiter Capitolinus. [Sidenote: Trajan’s second campaign in Dacia.] A somewhat similar series of scenes are represented in the sculptures which depict the second campaign. Perhaps the most interesting is that of the great bridge over the Danube, made of wood supported on stone piers, the foundations of which may still be seen in the bed of the river. Apollodorus, the architect of the Forum, designed this immense work, which crossed the Danube at a spot where it is not less than 1300 yards wide, near the village of Gieli. A permanent road into Dacia and secure communications with his basis of operations having thus been secured, Trajan gradually advanced from post to post, driving the Dacians into the mountainous parts of the country. The sculptures represent a number of skirmishes and assaults upon fortified places, but no regular pitched battle. At last the ghastly spectacle of the head and hands of Decebalus is exhibited on a board by two soldiers in front of the Prætorium. This disgusting scene is followed by a representation of the storming of the last strongholds of the enemy in the mountains, and a mournful procession of fugitives carrying away their goods and driving their cattle into exile forms the close of the sculptured history of the Dacian campaigns of Trajan.[76] In these curious bas-reliefs we have a treasury of information on the religion, the military science, the habits and dress of the Romans of the Empire far more valuable than ten thousand pages of descriptive writing. The lover of Roman antiquities will learn more by studying Fabretti’s engravings of these reliefs, or the casts at the French Academy at Rome, and at the Kensington Museum, than by much book-labour. The descriptions of Livy and Polybius, Cæsar and Tacitus, receive life, and movement, and interest as we look at the actual figures (oculis subjecta fidelibus) of the general and his staff; the Prætorian guards marked by their belts over the left shoulder; the fierce-looking standard-bearers and centurions with their heads covered by lions’ skins, the shaggy manes of which stream down their backs; the rank and file carrying enormous stakes; the master masons, sappers, and pioneers, with their axes and crowbars; the lancers, heavy and light cavalry, and royal chargers; the Sarmatian horsemen, clothed, both riders and steeds, in complete scale armour, and the Moorish cavalry, riding without reins.