There are said to have been twenty TRIUMPHAL ARCHES, of which five now remain, 1. The ARCH OF DRUSUS, on the Appian Way, erected in honor of Claudius Drusus. 2. The ARCH OF TITUS, at the foot of the Palatine Hill, built by Titus to commemorate his conquest of Judaea, The bas-reliefs on this arch represent the spoils taken from the temple at Jerusalem, carried in triumphal procession. 3. The ARCH OF SEPTIMIUS SEVERUS, built by the Senate in 207 A. D., at the end of the Via Sacra, in honor of the Emperor and his two sons for their conquest of the Parthians and Arabians. 4. The ARCH OF GALLIENUS. 5. The ARCH OF CONSTANTINE. There were two famous MAUSOLEA, that of Augustus, now in ruins, and that of Hadrian, which, stripped of its ornaments, is now the Castle of San Angelo. The COLUMNS commemorating persons or events were numerous. The most remarkable of these were erected for naval victories, and called COLUMNAE ROSTRATAE. The one of Duilius, in honor of the victory at Mylae (261 B. C.), still stands. It has three ship-beaks attached to each side. Columns were built in honor of several Emperors. That of Trajan is perhaps best known. The COLUMNA MILLIARIA was a milestone set up by Augustus in the Forum, from which all distances on the different public roads were measured. It was called _Milliarium Aureum_, or the golden milestone. CHAPTER XLVIII. COLONIES.--THE CALENDAR.--RELIGION. Colonies were established by Rome throughout its whole history. They were intended to keep in check a conquered people, and also to repress hostile incursions. Many were founded to provide for veteran soldiers; a practice which was begun by Sulla, and continued under the Emperors. No colony was established without a _lex_, _plebiscitum_, or _senatus consultum_. Religious ceremonies always accompanied their foundation, and the anniversary was observed. The colonies were divided into two classes, viz. Roman, and Latin or military. Members of the former class had all the rights of Roman citizens; those of the latter could not vote in the Comitia at Rome. The _Latini_, who were once Roman citizens, and who always felt equal to them, were uneasy in their subordinate position. But by the Julian law, passed in 90 B. C., they acquired the right of voting at Rome, and were placed on the same footing as Roman colonists. THE CALENDAR.