The outer wall of the choir aisle is one of the most interesting portions of the building, from an archaeological as well as an architectural standpoint. It shows three of the arched heads of small twelfth-century windows that used to light the earlier triforium gallery. One of these has now a fifteenth-century insertion beneath it. This is in the second bay from the transept. It is a small window with a cusped head and a square label-mould above it. In the same area of walling there are shown the levels of the cut string-course that ran along under the sills of the twelfth-century aisle windows. It is the same string and at the same level as it appears upon the south-west angle of the transept and the south-west tower of the west front. It shows, too, in the second bay, the level of the old abaci which ran across from each capital in the window jambs and stopped against the sides of the buttresses. There is also the continuous chamfer course that ran along the walls above the heads of these aisle windows. In proof of these things there is even now one of these same old windows in almost its original state within the little chamber known as the priest-vicars' vestry. This window is in the bay of aisle walling immediately against the transept wall. The string-courses of the old windows were continued round the later buttresses. In the fourth bay, above the point of the window arch, the curve of the original apse of the ambulatory is just traceable; but beyond this point eastwards the twelfth-century walling has disappeared until we meet it again in the lady-chapel. There is a small buttress in the fourth bay marking the junction between the two periods of masonry. In the second and third bays part of the twelfth-century top to the aisle walls remains. The roof may have had eaves originally, but now there is a parapet of about the same date as the present buttresses; and the projection of this parapet is carried upon the corbels that were carved and built in before the second fire occurred. The space between each corbel is bridged over by small single stones cut out to the shape of a semicircular arch.
The windows in the second, third, and fourth bays differ in size and shape from each other; that in the second bay has a pointed arch and no tracery, square abaci and the remains of carved capitals. The angle shafts and bases are gone. They were all inserted at about the same time; but that in the third bay has had some poor modern tracery without cusps added to it, and that in the fourth bay is a more recent, insertion than the one next to it. In the third and fourth bays just above the low chamfered base of the wall are three semicircular markings cut on the wall, but there is nothing to explain their existence. In the fourth bay close beneath the sill of the window is a stone built into the wall, upon which a dedication cross is cut. At the fifth bay the east walk of the cloisters joins the wall of the aisle; its roof partly hides a window, above which is a square panel of the fifteenth century. This panel indicates the position of a window, for the jambs and mullions of its tracery may be seen within the church. They are rebated for shutters, the old hooks for which also remain. The south-east angle turret of the presbytery has lately been
rebuilt; so also has that on the north-east angle. They are each of them octagonal in form, but differ in detail, in imitation of those they replace.
The large rose window in the gable of the East End is of about the same date as the vaulting over the south transept, since they possess kindred details. In design it is a simple circle, with seven others within it of equal diameter. Portions of the coping of an earlier and lower pointed gable are bedded in the wall. Under the string beneath the rose window are three windows grouped as a triplet, with no label moulding. The centre light is higher than the others. Though each has been much repaired, the early thirteenth-century detail has been retained. The abaci of the capitals are square. The windows have no tracery, and are probably quite fifty years earlier in date than the large rose above them.
The exterior of the small chapel to the south has a square weathered angle buttress. On its south side is a window of the same date as the rest of the chapel, and like the triplet in the gable of the presbytery in character and date. Its east end has been altered since the chapel was finished. First a small rose window, recently renewed, of the same date and type as that in the presbytery gable, was inserted under the earlier narrow window close to the gable point; then the original east window was removed, and a larger one was put in, having three lights and a traceried head with cusped work of late fourteenth-or early fifteenth-century work. The sill of the old window was lowered to give more length. Most of the window now to be seen is the result of recent restoration. Parts of the old string-courses remain in the walling.
The south side of the Lady-Chapel beyond the chapel just described has four bays. In each of these is a large three-light window. The western and smallest one was probably first inserted. Then the two eastern ones were put in when the two east bays were added to the older lady-chapel. The other window appears the latest of the four; or else may it not be that before deciding to lengthen the lady-chapel, the builders first began only with the idea of inserting some new windows in the older walls? But before this scheme had been executed they concluded that they would add bodily to the chapel; and in order to allow the chapel to continue in use while this was being done, they built the