It has been supposed by some that a chapter-house once existed within the paradise close by the west angle of the transept. The south end of the transept rises on the north side of the cloister garth. At the south-west angle a great part of the twelfth-century masonry in the broad flat buttresses remains. The south-east angle and buttresses are quite different. They are perhaps part of the work done during the thirteenth century, though it is possible that they were introduced when Langton inserted the large south window of the transept. This window has been very much restored since the seventeenth century, when it was almost knocked in pieces. Wooden props served instead of mullions for many years to hold up the tracery above. The repair that has been effected retains the old design. Above each angle of the transept is a turret, octagonal in form. Neither of them is complete. They were only required in the fifteenth century as a means of access to the roofs at the parapet level from the staircases in the angle buttresses. The gable of the transept rises above the parapet just described, but it is not in the same vertical plane as the face of the wall below. The top of this gable was for many years in a very wrecked condition. The design of the tracery in the rose window is in two orders, based upon equilateral triangles filled in with cusps.
Close to the ground on the south-west corner buttress are two string-courses. The lower of these is a billet-moulded course cut, like those to be seen on the south-west tower. Its presence here, and at this level, shows that this was the original level of the sills of all the old Norman windows on the outside walls until about the close of the twelfth century.
On the east side of this part of the transept, at the clerestory level, are two round-headed windows. Both originally were all of twelfth-century workmanship. But now the southern one has abaci, capitals, angle-shafts, and base, which are thirteenth-century work, and the early label-mould has been changed. The other window shows partly what was once probably the character of both of them. But the greater part of this window was restored when the central tower and spire were
rebuilt after 1861. Between the windows is a buttress that was introduced when the vault was added. The south-east angle on this side retains part of the twelfth-century flat buttressing. There are on this wall and the turret different types of masonry, which represent five distinct periods of building, from the twelfth to the nineteenth century. But the junction between the work of two of these periods, being a weak part, shows by the crack down the wall from the parapet that some movement has taken place here.
Projecting eastwards from the transept is the square chapel (now a vestry), which took the place of the early apsidal one. Neither of its three windows has any tracery. The window on the south side is pointed. The arch-mould is the same as that to the round-headed window on the east; but there is a label-mould over this south one and not on the other. The abaci are new, and the angle-shafts and bases as well, but the capitals are old, though decayed. The parapet on the south is of the same character and date as that over the wall of the choir, but earlier than that above the south window of the transept, which is of the same date as that on the south wall of the nave.
The roof of this chapel appears, from the raking channel on the transept wall, to have once been higher, with a sharper pitch. The finish to the present gable point has disappeared. On the east wall and on the south-west buttress of the transept there are two interesting old lead rain-water heads. The east wall of the chapel runs on northwards till it becomes a part of the buttress of the choir. The wall between the north buttress of the chapel and the buttress of the choir aisle close by is pierced with two small cusped windows of fifteenth-century date. Below these is a larger and sharply pointed arched head. It has no mouldings. But the square-headed small light under it has splayed jambs. This opening was probably once a round-headed twelfth-century window, as the old abacus is still in position.
The South Side of the Choir is externally divided into five bays. There are five flying-buttresses to carry down the vault thrusts, with a pinnacle above the buttress at the south-east angle. The first, second, and third bays from the east side of the transept have still the round-arched windows of the twelfth century set in the walling of the same date. But
it should be noted that part of the window in the first bay was rebuilt after 1861. The fourth and fifth bays have pointed windows, carved capitals, and angle-shafts. These, though now entirely renewed, were built when the whole of this part of the choir was added. Part of the walling for a few feet below the parapet was renewed at the same time. The flying-buttresses are thirteenth-century additions of the same date as the vaults within; and those three nearest the transept abut on parts of the twelfth-century flat buttresses. The flat projection was continued up to the parapet at a later date, probably when the parapet itself was built on. But the fourth buttress also abuts upon a slightly projecting flat strip of buttressing. In this case, however, but not in the others, the flat strip and the flying-buttress are of the same width and built as one piece of structure. The third and fourth flying-buttresses have a secondary, and apparently later, arch of fine grained white stone beneath their larger arches.
The copings on the backs of these buttresses are not weathered like those of the nave, and, except the one next the transept, each is covered with lead. There are no pinnacles to them above the aisle wall. The fourteenth-century builders had not touched them, as they did those south of the nave. There are, too, no gutters along their backs. It is curious that this method of carrying the water away from the upper roofs over the lower ones should not have been adopted when the parapets were put up.