It is elliptical in plan, is four stories in height; the three lowest are pierced with eighty openings, semi-circular arched, with columns and piers between. The first story is Doric, the second Ionic, and the third Corinthian. Each column and pier is raised on a stylobate, and the columns carry entablatures continuously around the building. [Illustration: Fig. 308.—Jewish Candlestick, Arch of Titus. (P. & C.)] An almost solid wall is the feature of the fourth story, which has a series of Corinthian pilasters, and projecting brackets for carrying the awning poles. The façade is built of stone quarried from the neighbouring hills, and the interior portions are built of brick. The dimensions are 620 ft. in length, 513 ft. wide, and 162 ft. in height. Double corridors run around the building on each floor, and it had seats for more than 80,000 spectators. Chariot races, mimic sea-fights, when the arena would be flooded artificially with water, gladiatorial combats, and fights with wild animals and bulls, were among the amusements of the Romans that were performed in the amphitheatres. [Illustration: Fig. 309.—Roman Composite Order, from the Arch of Titus.] Other monuments, such as triumphal columns and arches, were erected by the Emperors to commemorate their victories, and these were of the most elaborate and rich description. The column of Marcus Aurelius, known as the Antonine column, and the column of Trajan set up by that Emperor in Trajan’s Forum at Rome in commemoration of his victory over the Dacians, are the two best known of these commemorative monuments. The latter column has been reproduced, and a cast of it may be seen in the South Kensington Museum. The original is nearly 133 ft. high, and is richly sculptured with bas-reliefs on marble slabs fastened together in a spiral form around the central structure. The order is Doric, the shaft being set up on a large pedestal with very fine sculptures of figures, armour, and inscriptions. The triumphal arches are rectangular masses of masonry with arched openings, sometimes with one arch and sometimes three, a large one and two smaller ones, as the arches of Constantine and Septimus Severus; and sometimes smaller ones had piers and pilasters with a lintel entablature instead of an arch, as in the Goldsmith’s Arch in Rome. The arch of Titus (erected to commemorate the taking of Jerusalem A.D. 70), which is one of the finest of these monuments, is interesting for two reasons: one is that it has reliefs on it recording the capture of Jerusalem, with the representation of the seven-branched golden candlestick of the Temple (Figs. 307, 308), and the other is that the arch itself is one of the finest examples of the architectural order that was created by the Romans—the Composite—(Fig. 309), which is a grafting of the Ionic on the Corinthian.