BYZANTINE ARCHITECTURE. The ancient town of Byzantium, the modern Constantinople, was mostly in ruins when Constantine the Great selected it for the new capital of the Roman Empire. He rebuilt the old town and named it after himself, and in the year A.D. 330 the inauguration of the new capital was celebrated. Later on, under Theodosius, the Roman Empire was divided, and Constantinople became the capital of the Eastern portion. It was the great connecting-point between the countries of the East and the West. The inhabitants of the new city being mostly Greeks, the native artists and architects employed by Constantine imparted a decided Grecian character to the ornament and decoration, especially of the churches and other buildings that were erected by this emperor. The occasion of the new political change and the rapid spread of the Christian religion served to give a great impetus to the building and lavish decoration of churches and public edifices. Although the new architecture was founded on the Roman originals, yet in the hands of the Greeks both architecture and ornament assumed a new and original character. From the time of the founding of Constantinople to the date of Justinian’s reign (A.D. 527-565), when the great church of Santa Sophia—holy wisdom—was built, on the ruins of an older church that was said to have been burnt down, we can guess that it must have been a time of experiments and developments from the basilica type of building to the well-defined domed style of architecture known as the Byzantine. The timber-roofed and vaulted style of structure now gave place to the dome, which resulted also in a change of the plan to the square form, instead of the rectangle. During the two hundred years previous to the building of Santa Sophia, the problem of dome construction, with others of a difficult nature in building, had been successfully solved by the Greek architects of the Eastern Empire. Justinian employed the Greeks, Anthemius of Thralles and Isidorus of Miletus, as the architects of Santa Sophia, and they succeeded in erecting a marvellous structure that may justly be reckoned as one of the wonders of the world. Four vast piers, arranged on a square plan, support four solid arches of masonry, semicircular in shape, and 100 feet span each. The four triangular spaces at the corners and the spaces formed by the angles, the semicircular arches and portions of the ring of the dome, are filled with “pendentives,” which may be described as continuations of the dome. These pendentives partly support the dome, and the other points of support are on the backs of the great arches. The four pendentives meet in the circular ring from which the dome springs. The dome is 46 feet in height from the level of its base, and 107 feet in diameter, and is rather flattish in shape.