With writers of about fifty years ago, it was a favourite theory that the Christians converted the old basilicæ into churches, and that the "Halls of Justice" erected by the Romans in this country were also converted into Christian churches, and some authorities point to the walls and arches of Brixworth church in confirmation of this theory. The late Mr. J. W. Brewer, however, stated that unfortunately for this theory, no single example of a basilica being converted into a church has been found in this country and he himself held the theory that the word basilica was used by the Romans to describe any building which was supported by internal columns, and in that way the name came to be applied to Christian churches. As we have seen, the early Christians, after a short time, became dissatisfied with these buildings adapted from Pagan types, and the Byzantine form of church arose, the first people who practised this style of building being the Greeks. The style spread with rapidity all over the East, the great church of S. Sophia being its largest example and the smaller, but more perfect, church of S. Mark at Venice giving us the best idea of this form of church architecture. Largely modelled on this style, also, are the circular baptisteries of Italy and the round churches of England, France and Germany, the modern Russian churches and all the Mohammedan mosques. The Latin churches did not greatly favour this style and their use of it was confined, with few exceptions, to baptisteries, monumental chapels and the like, but for parochial, cathedral and monastic churches, the oblong plan was retained and ultimately developed into the Gothic church with its nave, transepts and chancel. The changes which the Christian basilica at first underwent were simple, _viz._, the use of the arch instead of the straight lintel, or the placing of an entablature between the columns; a little later, about the tenth century, the old wooden roof of the basilica gave place to the arched roof or vaulting, so called from its being composed of a series of vaults. The styles called Romanesque and Lombardic are but geographical varieties of the same architecture and from these the Saxon and Norman styles were soon to be developed. The vaulted basilica church soon became common over the north of Europe, the two most important and practically unaltered examples being the cathedrals of Speyer and Worms, in Germany, although our Anglo-Saxon cathedrals of Peterborough, Ely and Norwich may, so far as regards their naves, be justly regarded as the offspring of the vaulted basilica style of building.