64 Byzantine Architecture. of Byzantine architecture. But the best example of any is the church of St. Sophia, which is now the great mosque of Constantinople (Fig. 32). It was commenced by Justinian in 532, and completed in 537, but was much injured by an earthquake twenty years later. It is of no great beauty externally, but its internal arrangements are of a surpassing grandeur. The narthex consists of two fine halls, one over the other, and the church itself is almost a square, being 229 ft. north and south by 243 ft. from east to west, surmounted in the centre by a vast dome, 107 ft. in diameter, and rising to a height of 182 ft. from the floor of the church. East and west of this are two semi-domes of the same diameter, which are cut into by three smaller half-domes, supported on two tiers of columns. On the lower range of these columns stands a gallery, running all round the church except at the apse. North and south the galleries are surmounted by a wall instead of the semi-domes, and these walls are pierced with twelve small windows. The double narthex, galleries, and apse are lighted by two rows of windows, which extend all round the church. The central nave is lighted by one great western window and a number of smaller openings pierced in all the domes just above the springing. Another church at Constantinople, in which later Byzantine architecture can be studied in its completeness, is that called Theotocos (Mother of God). It was probably erected about the end of the tenth or beginning of the eleventh century. In other parts of the ancient Greek empire many ex- amples of Byzantine architecture still exist. At Salonica there are the remains of many churches. In Athens there is a small cathedral decorated internally with mural paint-
