murdered. The posthumous veneration of Becket transformed the cathedral into a place of pilgrimage, necessitating both expansion of the building and an increase in wealth, via revenues from pilgrims, in order to make expansion possible. Rebuilding of the quire In September 1174 the quire was severely damaged by fire, necessitating a major reconstruction, the progress of which was recorded in detail by a monk named Gervase. The crypt survived the fire intact, and it was found possible to retain the outer walls of the quire, which were increased in height by in the course of the rebuilding, but with the round-headed form of their windows left unchanged. Everything else was replaced in the new Gothic style, with pointed arches, rib vaulting, and flying buttresses. The limestone used was imported from Caen in Normandy, and Purbeck marble was used for the shafting. The quire was back in use by 1180 and in that year the remains of Dunstan and Ælfheah were moved there from the crypt. The master-mason appointed to rebuild the quire was a Frenchman, William of Sens. Following his injury in a fall from the scaffolding in 1179 he was replaced by one of his former assistants, known as "William the Englishman". Trinity Chapel and Shrine of Thomas Becket In 1180–1184, in place of the old, square-ended, eastern chapel, the present Trinity Chapel was constructed, a broad extension with an ambulatory, designed to house the shrine of St Thomas Becket. A further chapel, circular in plan, was added beyond that, which housed further relics of Becket, widely believed to have included the top of his skull, struck off in the course of his assassination. This latter chapel became known as the "Corona" or "Becket's Crown". These new parts east of the quire transepts were raised on a higher crypt than Ernulf's quire, necessitating flights of steps between the two levels. Work on the chapel was completed in 1184, but Becket's remains were not moved from his tomb in the crypt until 1220. Further significant interments in the Trinity Chapel included those of Edward Plantagenet (The "Black Prince") and King Henry IV. The shrine in the Trinity Chapel was placed directly above Becket's original tomb in the crypt. A marble plinth, raised on columns, supported what an early visitor, Walter of Coventry, described as "a coffin wonderfully wrought of gold and silver, and marvellously adorned with precious gems". Other accounts