halfway round the arch they are cut back to receive the arch, which is there commenced. In the same way the cinquefoiled arches of the upper arcade have their lowest cusps formed by the stone abacus, the intermediate cusps by bricks laid horizontally and cut at the edge, and the upper central cusp alone has any of its masonry constructed as an arch. The upper stage of the mosque called De las Tornerias is Moorish work of the same plan as the Cristo de la Luz; but I am much inclined to doubt whether it is equally ancient. The rosettes cut in the vaults, and the cusped openings, give this impression, and the vaults are quadripartite and domical in section, the centres of the nine small bays of vaulting being raised higher than the others, and having two parallel ribs crossing each other both ways, in the way I have already noticed in the Chapter-house at Salamanca, and the Templars’ Church at Segovia. There is, so far as I know, no other mosque in the city so little altered as these; but among the churches some are said to have been first of all built for mosques. San Roman is one of these. It was converted into a parish church at the end of the eleventh century,[211] and the column and arches between the nave and aisles are probably of this date. The arches are of the horseshoe form, and the capitals are, I think, commonly quoted as some of the earlier works re-used by the Moors. But I very much doubt whether their style justifies my attributing to them any date earlier than the eleventh century. The church was not consecrated until June 20th, 1221, but there can be no doubt that it was built before this date. The noble steeple is one of the works built by Moorish architects for Christian use, and it will be better, perhaps, to reserve it for description with other works of the same class.