VII. The next step, _c._ 1325, was to build another bay to the choir, thus joining it up to the Lady chapel. In this bay was placed a new shrine of St. Chad. But even this was not enough for the canons. They were seized with the mania for floods of light and acres of stained glass which raged like an epidemic through the fourteenth and fifteenth and sixteenth centuries. They pulled down all the choir except the piers and arches of the three westernmost bays—they would have removed these also but for fear of bringing down the central tower—built new piers and arches in the eastern bays, and a new clerestory along the whole length of the choir with huge windows of flowing tracery, two only of which are left. At the same time they replaced all the lancets of the aisles by big Curvilinear windows. The jambs of the clerestory windows they enriched with bands of quatrefoils; one of the windows of the south aisle of the choir, opposite to which the tomb of Bishop Langton formerly stood, and beneath which good Bishop Hacket’s tomb is now placed, has big crumpled leaves running up the jambs. The junction of the early Lancet piers and capitals with those of the fourteenth century is well seen in the vaulting and in the third pier from the central tower. Between the bays were placed statued niches, as in the contemporary church of St. Mary’s, Beverley, from which rose the vaulting-shaft. The whole design should be compared with the presbyteries of Wells and Chester, which were in course of “restoration” at the same time and in the same ruthless fashion. In the choir aisles is a delightful arcade of bowing ogee arches. [Illustration: CHOIR.] About the same time, or a little later, were built the central gable of the west front and the south-western spire. VIII. PERPENDICULAR AND TUDOR.—The equipment of the presbytery was completed, _c._ 1390, by the erection of a magnificent altar-screen after the fashion of those at Winchester and St. Albans. Six of its canopies are used up in the present sedilia. The northern spire also was copied from the southern one. More big windows were inserted in the transepts and the west end of the nave. The latter has been replaced by a modern geometrical window; that of the north transept by a fine quintet of lancets, largely composed of fragments of the original thirteenth-century window. Finally, the whole cathedral was rendered fireproof by the erection of vaults under both transepts and the central tower. The south transept, however, would seem to have had a vault before—but it may have been of wood—for a little lower than the Perpendicular abacus of the vaulting-shaft is one of the thirteenth century. To this period belongs the gallery of St. Chad’s chapel.