The west doorway and the north door-piece are interesting; the former, the south half of which has perished, and which was finished with a sloping gable and stone roof, is regarded as a rich specimen of the elaborate carved work that characterised the late Norman period. "The jambs contained five detached shafts set in nooks, and having Norman bases and carved caps. Over each of these shafts there springs a circular order, carved with rich Norman ornament, now, however, very much decayed. The jambs of the doorway also formed moulded shafts, supporting their order in the arch."[426] The door-piece of the north transept wall is a prominent feature, projects 4 feet 6 inches from the main wall, has two stories, and is roofed with a sloping stone roof. The shafts have the usual Norman caps and bases, and the mouldings of the arch are pronounced to be peculiar in their profile. The outer one is enriched with small medallions, the central with the billet, and the inner one with rosettes. Above the archway there is an arcade of interlacing round shafts--the shafts, which were destroyed, having Norman caps. "The tympanum of the gable is covered with a reticulation of round beads or rolls."[427] The south and west sides and a small portion of the north and east sides of the tower remain. It is 35 feet square over the walls, and "is carried up with plain masonry externally, but the interior has immediately over the great arches of the crossing an arcade of round moulded arches, supported on triple shafts similar to those of the choir. Above this arcade is another story containing simple round arched openings, which are lighted on the exterior by circular windows containing quatrefoils. Over this tier is the upper story, which contains three pointed and deeply-recessed windows on each side of the tower. Broad, flat buttresses are placed at each angle of the tower, similar to those of the main building, and these were, no doubt, originally finished with turrets like those of the transepts.... The upper part of the tower is later than the lower part. This is apparent from the pointed windows of the top story and the quatrefoiled circular windows of the story beneath. The lower story immediately over the great arches is, without doubt, of about the same date as the choir."[428] There were probably similar staircases in other parts of the structure now removed, but the approach to the upper floors is now by one staircase in the N.W. angle of the transept. Passages between the arcades and the outer walls went round the building on every floor, and in the angles of the tower there are small wheel stairs leading to every floor, and passages running round the tower on every story. These arcades and passages have tended to weaken the structure, and it has been found