The figures which stand in front of the attica have the Dacian costume, and have been removed from some one of Trajan’s buildings. Upon the side of the central archway can be still seen the traces of nails which fastened some Roman ensigns to the stones. Similar traces of nails are to be seen upon the arch of Severus as before mentioned. The inscriptions over the smaller arches refer to the decennalia or vicennalia, a festival celebrated after the time of Augustus every ten years of an emperor’s reign when he was supposed to have the imperium conferred upon him afresh. The meaning of the expression VOTIS X. VOTIS XX. seems to be that these inscriptions were put up on the “vota” or day when vows were made for the emperor’s safety at the beginning of the tenth and twentieth years of his reign. This is not an uncommon signification of the word “vota” in later Latin. The day which was usually called vota was either the first or third of January, and the custom of offering these vows was retained long after Christianity had been nominally made the state religion, so that it is not surprising to find it alluded to on Constantine’s arch.[68] The words on the other side of the arch SIC. X. SIC. XX. may be interpreted as the form of words used in making vows to the emperor. “Sic x. annos regnet; sic xx. annos regnet.” “May his reign last ten years more or twenty years.” The larger inscription which is cut upon the attica on both sides shows that the arch was erected in honour of the victory of Constantine over Maxentius, and the union of the empire under one sovereign. It is not, however, certain that the arch was built in the first year of Constantine’s sole reign, for not only do the words INSTINCTU DIVINITATIS “by inspiration of the Deity,” seem to indicate a more decided leaning to Christianity than Constantine showed at the beginning of his reign, but the title of Maximus, which is found in the inscription, does not occur in the coins of Constantine before the tenth year of his reign. The solid contents of this arch, as may be seen by ascending the staircase which is entered by a door at some height from the ground at the end nearest the Palatine Hill, are mainly composed of pieces of marble taken from other buildings, and it has even been suspected that the plan itself, which in beauty of proportion surpasses the Arch of Severus, was borrowed, together with the materials, from Trajan’s Arch or some older building now destroyed. [Illustration: The Coliseum, from the Palatine Hill.] [Sidenote: The Coliseum.]