The outer narthex has a single door to the exterior, placed on the central axial line, and is planned symmetrically. The central bay is larger than the others, and is covered by a dome vault resting on shallow wall arches. On each side are two bays covered by similar dome vaults, but as the bays are oblong, the wall arches are brought forward strongly so as to give a form more approaching the square as a base for the dome. The transverse arches are strongly pronounced and have wooden tie beams. At the south end two bays are returned to form an entrance to the parecclesion. In these the transverse arches are even more strongly marked and rest on marble columns set against shallow pilasters. The cubical capitals are of white marble and very beautifully carved with figures of angels and acanthus wreaths. Any marble revetment which may once have covered the walls has disappeared, but mosaics depicting scenes in the Saviour's life still decorate the vaulting and the lunettes of the arches, whilst figures of saints appear upon the soffits. The mosaics are damaged and have lost some of their brilliancy; the background is of gold, and the mosaic cubes are small, averaging about 1/8 to 3/16 of an inch. [Illustration: FIG. 100.] The parecclesion is entered from the return bays of the outer narthex through a triple arcade, now partly built up. The capitals of the columns are Byzantine Corinthian, and retain sufficient traces of their former decoration in dark blue, gold, and red to give some idea of the effect of colour on marble in Byzantine churches. The parecclesion is in two bays. The western bay is covered by a high twelve-sided drum dome, with windows in each side separated by flat ribs. In the compartments are figures of the archangels in tempera, with the legend, 'Holy, Holy, Holy, is the Lord God.' The eastern bay is covered by a dome vault, and terminates in an apse semicircular within and lighted by a triple window. It has neither prothesis nor diaconicon of its own, but communicates with the original diaconicon of the main church. The three transverse arches in the bay are tied with wooden tie beams carved with arabesques and retaining traces of gilding. On the north and south walls of the western bay are large arches enclosed in square frames and with finely carved archivolts. Above the south arch is a slab inscribed with the epitaph to the memory of the celebrated general Tornikes. There are no indications of an entrance under the arch. It may have covered a niche, now built up, intended to receive a tomb, possibly the tomb of the sebastocrator Isaac.