The nave and transept clerestory windows mainly depict saints and Old Testament prophets. Some Romanesque churches have barrel vaulted ceilings with no clerestory. The apse clerestory, the upper section of the ambulatory, is recessed slightly inward. Sometimes another gallery set into the wall space above the triforium and below the clerestory. The nave was largely rebuilt in about 1485 with a Perpendicular Gothic clerestory. The elevation is in three stages, arcade, triforium gallery and clerestory. The arches of the new nave arcade were exceptionally high in proportion to the clerestory. The ceiling of the nave, above the clerestory, is eight stories high. Inside are spiral staircases ascending to the clerestory and the vaults of the naves. There is a tunnel-vaulted passage between the inside and outside window openings of the clerestory. The halls were longitudinal, aisled, and flooded with light from large clerestory windows. The width between the overhanging clerestory walls is . Another important element in creating daylighting is the use of clerestory windows. Dietrichson emphasized the clerestory, arcades and capitals. The north and south arcades and most of the clerestory windows are Early English Gothic.