have been made worse by the removal of a superb Perpendicular stone rood-screen, crowned, as at Exeter, by a Renaissance organ. The removal of this has impaired the general effect of the interior, much lessening the apparent length of the cathedral. As usual, only the aisles and apses of the Norman cathedral were vaulted; the aisles here, as at Southwell, are vaulted in oblong compartments. It was dedicated to St. Peter, and served by secular Canons, of whom in 1520 there were thirty-one. In the triforium of the choir were semicircular transverse arches, precisely as in the choir of Durham. [Illustration: PRESBYTERY.] II. LATE TRANSITIONAL AND EARLY LANCET, from the fire of 1186 to the consecration of 1199, when the cathedral was re-dedicated to the Holy Trinity. About 1180 some work was going on in the western part of the Lady chapel, but in a great fire in 1186 the roofs and fittings of the whole cathedral were burnt, and the clerestories were no doubt damaged by falling timbers. The destruction, however, was by no means so great as at Canterbury in the fire of 1182, and no such drastic process of rebuilding was necessary. Bishop Siegfried confined himself to four objects: (1) To fireproof the cathedral by covering it with a stone vault, provided with the necessary buttresses and flying-buttresses. And as the clerestory which had to support the vault was much damaged, its inner arcade had to be rebuilt. (2) To replace the apse and ambulatory and chevet by a rectangular retro-choir with square eastern chapels. (3) To replace the transeptal apses by similar chapels. (4) To get rid of some of the rough and heavy appearance of the ground-story of the whole church. He did not touch the triforium. Siegfried probably commenced with the choir, which was most wanted. The masonry of the ground-story had probably been calcined by the roof-timbers blazing on the floor; the inner face of this was cased with good Caen stone. As at Canterbury, great use was made of Purbeck marble, in which were built angle-shafts and capitals to the piers, hood-moulds for the pier-arches, string-courses below and above the triforium, and arcading to the clerestory. In front of each pier a triple vaulting-shaft was run up, with a marble capital, supporting the new quadripartite vault. Externally, the clerestory wall was supported by flying-buttresses of heavy archaic type, similar to those of the choirs of Canterbury and Boxgrove. Later on, the same treatment was extended by Siegfried and his successors to the nave and transepts.