The building must certainly have been roofed before it was decorated, and if Stubbs is accurate, and there is no reason to suppose that he is not, the work was completed by Thoresby. Thoresby died in 1373, and if he finished the presbytery, there was a gap of seven or eight years between its completion and the beginning of the choir. There is internal evidence to support this presumption. The presbytery, though Perpendicular in its main features, shows many traces of the transition from the curvilinear Decorated to the Perpendicular style, especially in the tracery of the great east window and the clerestory windows. In the choir proper these traces have vanished, and the work, though apparently of the same character as that in the presbytery, is altogether Perpendicular. A lapse of ten years in the continuity of the work would account for this change, and becomes still more probable when we consider that the circumstances of the time were not favourable for great expenditure on building. The presbytery had been completed unusually quickly. Indeed, we know that L627 were spent upon it in one year, and this was an unusual amount. The average expenditure, for instance, on the choir of Ely was L318. It was natural, therefore, that there should be a halt to collect further funds. The work of the choir itself proceeded much more slowly. There was a complaint in 1390 on the archbishop's visitation--_quod fabrica ecclesiae negligenter tardatur_--and it was not roofed in until 1400. The contract for the glazing of the great east window is December 10, 1405--that is to say, thirty years and more from the date of its construction. But there is nothing unusual in this. It was customary before filling windows with stained glass to cover them with linen cloth which admitted a sufficient amount of light, or to glaze them with plain glass; and it was only natural that a long time should elapse before stained glass could be supplied to the largest window in the world. Burying was begun at the east end soon after 1400, and Scrope was buried there in 1405. Bowet's monument also was erected there in 1415, while he was still alive. A new high altar was projected in 1418, and the new crypt was fitted with iron work and paved in the same year. The building of the choir had caused a subsidence in the crypt, so the work of Roger and others was broken into fragments and patched together, older capitals being placed on Roger's pillars, in the condition in which we now see it. Nothing is known of the history of the vaults of the choir and eastern transepts. Like those of the nave and transepts, they are of wood, though of the same shape and design as a stone vault.