The nave consists of seven bays on each side, divided by piers, alternately circular and octagonal, like those in the choir, with triple vaulting shafts on the north and south sides (the central shaft in each case being of Purbeck), and a single shaft on the east and west, corresponding with the interior order of the arches. The vaulting shafts are banded. The deeply moulded arches are somewhat loftier and more acutely pointed than those in the choir, placing the triforia on a slightly higher level, but the triforia of nave and choir are alike in that in both cases they consist of four arched openings in each bay. Every bay is walled off from its neighbours on either side, but has an opening at the back into a passage above the aisles, which is continuous throughout nave and choir. In the westernmost bay on either side, the triforium arcade has a wall immediately behind the shafts. In the other bays it is recessed, and open above the level of the aisle vaulting. In these respects the architect has reversed the old arrangement, as in the original nave the two westernmost bays had open triforia, the others simply containing a shallow arcading. This arrangement, taken in conjunction with traces of an incipient tower discovered within the two western bays, seems to show that these bays were intended to form a narthex, or vestibule, to the church, but it does not appear that the tower was ever erected, or that the vestibule ever went beyond the conception. The clerestory is lighted by plain lancet windows, enclosed in an elegant arcading. Entering the church by the great doorway at the south-west, and looking towards the east, we get a fine perspective of over two hundred feet, including the nave arcading in its three stages, the groined and vaulted roof, and a good view of the choir, terminating in Bishop Fox's fine stone screen, with the three-light window above it. [Illustration: _Photo._ _G.P. Heisch._ THE CHOIR VAULT.] In both aisles there is an interesting series of modern windows intended to memorialise the great names associated with the Church, the Borough of Southwark, and the history of England--all excellent specimens of the revived art of glass-staining, and all at present designed by Mr. C.E. Kempe. The visitor will find it convenient to begin his examination of the interior at the =North Aisle=. The window at the extreme west end of this aisle contains a figure of St. Augustine of Hippo, as Patron of the Augustinian Canons, introduced early in the twelfth century, when the Collegiate Church was transformed into a monastery.