The 13th and 14th centuries gave the church its ornate chancel arch, with four depths of moulded spandrels and foliage capitals set on Purbeck marble piers. An engraving of the church in 1806 shows the original lower ridge of the nave roof, giving a better proportion to its relationship with the fine tower with its carved pinnacles and strange gargoyles. At that time there were only four round clerestory windows on each side of the north and south walls of the nave. In the 1860s the roof was raised and the clerestory windows increased to six on each side; Pevsner writes "The clerestory windows, however, are Victorian, of an oddly playful kind, quite out of keeping with the church or Wiltshire – pentagon and hexagon surrounds and cinquefoils and sexfoils".