the eighteenth century. The rotunda is lighted only by a circular opening 30 feet across in its center, which is said to be far the noblest conception of lighting a building to be found in Europe. The great bronze doors 30 feet high are still in place, and were originally plated with gold. The gilded bronze roof tiles were used by Urban II to make the great canopy in St. Peter's. The exterior lower story was faced with marble above which the wall was covered with stucco decorated with pilasters. The dome is a marvellous piece of construction. As we have said above, it is the ancestor of all later domes in the world. Later development of Roman work under the Antonines, 138-161 A.D., was expressed in the attention paid to the embellishment of cities, especially in Asia Minor. Roman temples were the homes of deities more frequently than they were the halls of worship, and were often used for secular purposes and for exhibition of works of art. For instance, the Temple of Concord was sometimes the meeting place of the senate; that of Castor and Pollux was an office of weights and measures; that of Saturn a treasury, while the Temple of Mars Ultor was filled with statues of famous generals. The cells were usually uninterrupted by columns, four only having interior columns forming aisles. The largest temple in Rome was that of Venus and Roma, built by Hadrian near the Colosseum; two temples back to back, surrounded by a double row of columns 450 feet by 700 feet, within a peristyled court 650 feet by 1000 feet, the columns of granite and porphyry. The legend is that Numa Pompilius in 715 B.C. built a wooden circular temple to Vesta, goddess of the hearth, as symbolical of the primitive circular huts, and successive temples to Vesta retained that form. Hence it has been assumed that the circular Roman temple was not derived from the Greek tholos at Epidaurus. The existing Vesta temples are later than these; the one at Tivoli is probably of the time of Augustus. It has a cella 21 feet in diameter surrounded by 18 Corinthian columns with a fine entablature. Whereas the Greek theatre was excavated on a hillside, this was only occasionally true of the Roman, but where the towns were on level ground their theatres were built up in tier after tier of seats with vaulted corridors beneath them, the outer corridors being lighted by open arcades; staircases ascending to the seats. The corridors served for shelter in rain as did the covered porticoes of excavated theatres. The arches of the exterior were between engaged columns of the three orders of architecture - Doric, Ionic, and Corinthian superposed, each with its entablature, creating a most impressive motive of architecture which henceforth, whether with the engaged columns or with pilasters only, was universally used in classic work. The tendency in late Greek theatres was to bring the stage out into the orchestra so that the actors might be near the audience. In the Roman theatre the orchestra was a semicircle with the front of the stage upon its diameter, and the scena, or back wall of the stage, made into a high and elaborate piece of architectural design with arches, columns, niches, and statues, and with a rich wooden cantilever roof projecting at an angle of 30 degrees from its top over the stage. Again in the Greek theatre the scena had no connection with the walls of the theatre, whereas in the Roman it joined them and made one architectural enclosure. On either side and back of the scena were great halls or foyers, used for rehearsals and for shelter from storms. Arcades and colonnades were carried around above the top row of seats, and above these masts were placed from which cords were stretched. On these was run the velarium or awning to protect the audience from the sun. The stage at times was 40 feet deep and 200 feet wide. The earliest amphitheatre known is that of Pompeii, about 180 B.C., elliptical, and about 300 feet by 450 feet. The largest is the Colosseum in Rome, built upon the site of Nero's |