Constantine the Great, in the early part of the 4th century, embraced Christianity. The new religion required structures capable of holding large assemblages of people at certain periods; and notwithstanding the magnificence of some of the Roman structures, none could be found appropriate to the required use, save the Basilicas, or Halls of Justice, at Rome. The form of these structures was oblong, and the interior consisted of a central avenue and two side aisles, divided from the centre by a double row of columns, the central avenue terminating in a semicircular recess with the roof rounded off. It will be at once apparent that such buildings were admirably adapted to the purposes and observances of the new religion; and, accordingly, in A.D. 323, when Constantine removed the seat of empire from the West to the East, from Rome to Byzantium (Constantinople), the Roman Basilica probably served as a model for the Christian churches which he rapidly raised in his new city. But on this point we have little authentic information; time, the convulsions of nature, and the destructive hand of man, have long since lost to us the original churches built on Constantine’s settlement at Byzantium, and the oldest monument with which we are acquainted, that of Santa Sophia, built in the early part of the 6th century by Justinian, bears no relation in its plan to the long basilica of the Western Empire. [Illustration: Greek Cross.] [Illustration: Latin Cross.] The great characteristic of Byzantine church architecture was a plan formed on the Greek cross, and surmounted at its points of intersection by a central dome. The direct imitation of the antique capitals was eschewed, and a foliated capital was introduced in its place, varying considerably in pattern even in the same building: the arch was in general semicircular, and the use of mosaic ornament universal, but it was some time before the Byzantine style received its full development; for the earlier Christians generally maintained a profound antipathy to all Art, as ostentatious, and savouring overmuch of worldly delights. It is not, however, in the nature of man to exist for any length of time in this world, wondrously adorned as it is by its Divine Creator, without imbibing a love for the adornment so profusely displayed around him. This natural feeling, which St. Augustine and the stricter Christians vainly sought to decry and repress, was strengthened and aided by the more forcible notion of holding out some attraction to the pagans, who, accustomed to the ceremonies and charms of their old rites, might be repelled by the apparent gloominess of the new creed. As the number of converts increased, a demand for church ornament made itself felt, and Art once more awoke, not in the excelling beauty of its former life, but rude, unpolished, and crippled by religious necessity, which placed, as in Egypt of old, a restriction upon the forms of nature, lest