BRISTOL AND ELY same spatial motifs in the sacristy of the cathedral. Here the ribs of the little vault are accompanied by a skeleton of secondary flying ribs starting at a lower level than the others, shooting through the air and meeting the primary ones at the central boss. The effect is again one of deliberate and pleasing confusion. Classic Gothic ribs, just like classic Gothic arches, keep strictly to the strata of space assigned to them; they never stray into others. At Ely more than anywhere else the new attitude towards space has found an adequate form. Between 1322 and 1342 the crossing of the cathedral was rebuilt in the form of an octagon. The choice of this shape by the designer, who probably was the King's carpenter, Master William de Hurle, can have been nothing but a deliberate attempt at breaking the I3th-century's discipline of right angles. The diagonal axes, with their large windows and flowing tracery, destroy the precise dividing lines between nave, aisles, transepts and choir whichhad been the groundwork in the plan and elevation of a classic Gothic church. It has been argued that the glass of Amiens or the Sainte Chapelle also breaks this logicality of the earlier Middle Ages by opening the room towards a mysterious transcendental world. That is not so; the sheets of glass may give a diaphanous character to the enclosure, but it is an enclosure all die same. It doesn't really allow the eye to wander into dirn^ incomprehensible distances. The octagon of Ely has this very effect, an effect of surprise and ambiguity. The Lady Chapel at Ely (1321-49) achieved the same aim by subtler and more delicate means. The rectangular chapel isolated from the main building, as only chapter-houses usually are, has all the way round an exquisite arcading with crocketed ogee arches gathered together by larger three-dimensional or nodding ogee arches (pi. xxxvi). Ogee-curved quatrefoils with seated figures fill the spandrels. The arches are covered with a luxuriant growth of vegeta- tion, no longer as crisp as that of the I3th century, but with its un- dulations of knobbly leaves and its intricacy of minute detail at once more sophisticated and, strangely enough, more uniform in its general appearance. This is due to a treatment that makes it impossi- ble to isolate part from part/as one could in looking at the leaves of Southwell. Now all one sees is an incessant ripple and flow, lights and shadows whisking over bossy surfaces, fascinating but far re- moved from the clarity of a hundred years ago. The three-dimensional ogee arch is a motif of great significance. It does what the octagon does in Ely Cathedral, and the piers with- 59