The bricks are as a rule about fourteen inches long and two inches thick; some vaulting bricks brought from the ruins by the porch on the east measured fourteen inches square and two inches thick; on one side of them were scratched lines probably made by the three fingers of the maker, and on the other was an oblong label inclosing an inscription (1); another had a different inscription (2); and a third, not from this vault, but of the same size, was also inscribed (3). [Illustration] [(1) Reads Constantius or Constantine. (2) May be rendered “the church which is being erected,” by reading a participle of ἐγείρω for the second and third letter. (3) This is also given in the _Revue Archéologique_, 1876, with some slight differences in second and third lines; it is there said to have been found between SS. Sophia and Irene. It probably reads, “Lord, help Philemon: Indiction 7.” The two first vowels of Philemon have changed places, and the contraction form after “ΙΝΔ” is also turned the wrong way.] At the base of the dome the bricks are 27 × 9 inches, and two inches thick. Some appear to be twenty-seven inches square; but at the apex of the dome, by the hole intended for the lamp-chain, the thickness is twenty-four inches. There was no trace of the light bricks made in Rhodes which the Anonymous mentions; although in the pendentives a light substance, whitish, with impressions of plants in it, was used in irregular masses. The mortar has a red colour, and was evidently mixed with crushed brick; the joints are from one to two inches thick. The marble of Proconnesus, which somewhat resembles the architectural marble of Carrara, is employed for the cornices, capitals, and bases of the columns, and for the windows. In Salzenberg’s plans the materials are expressed by different depths of tint; the darkest being marble, slightly lighter is stone, and a still lighter brickwork; the additional buildings are represented in the lightest tones, and the Turkish buildings with strokes and dots. _Construction._--The outside walls average a height of seventy feet: those on the north and south have a thickness of three and a half feet, that on the east is four and a half feet, and that on the west between the nave and narthex five feet. Where the arches rest on the walls there are piers which project about two feet: thus the west wall, for instance, has in parts a thickness of seven feet. As a general rule, the interior vaults of wide span continue through the walls, and appear as arches on the outside face. The window and door openings are semicircular. The marble finishings were inserted after the completion of the walls.