The choir, where, on the completion of the south arm of the transept, Bishop Nivelon of Chérisy continued the building of the Cathedral (1200–1212), is one of the earliest examples of Pointed Gothic—so-called on account of the sharp outline of the arches. A notable characteristic of this is the transformation of the wide galleries of the triforium into a narrow gallery, which gives greater importance to the wide arches of the ground floor and to the high windows of the upper story. Its general plan is similar to that of the nave, built immediately afterwards: lofty wide arches, narrow triforium, high windows (but without mullions, forming a single bay), and pointed vaults of rectangular plan. The Choir is flanked by side-aisles, off which open, on each side four rectangular chapels with groined vaults. The second chapel of the aisle has an inscription recording the date on which the Canons took possession of the Choir: _Anno milleno biscenteno duodeno hunc intrare chorum Cepit grex canonicorum tercio idus maii._ (In the year 1212, on the third Ides of May, the Canons first took possession of the Choir). [Illustration: THE CHOIR. _On the left and at the back sand-bags protected the art treasures._] The south side-aisle communicates with the chapel attached to the south arm of the transept by a 15th century vaulted corridor (_D on plan p. _18) in which there is a fine 16th century statue of the Virgin and Infant seated. The two side-aisles continue round the semi-circular apse, forming an ambulatory surrounded by five shallow radial chapels. The central chapel is consecrated, as usual, to the Virgin. The pointed vaults of the chapels unite with those of the ambulatory, eight pointed ribs meeting in the same key-stone. The choir, scarcely touched by enemy fire up to December 1916, suffered more serious damage then and in January 1917. Shells pierced the vault in two places and also penetrated several parts of the triforium wall, breaking the arches. In the apse, portions of the vault were injured and parts of the 13th century stained-glass, which it was not possible to remove from the high windows, were damaged. The vital parts of the choir escaped serious damage, and it was possible during the second half of 1917, to carry out temporary repairs after the retreat of the Germans. At the same time, in order to make the choir—as well as the transept, which had also escaped serious injury—once more available for public worship, a partition was built shutting off the nave (_photo p. _24). This protective partition shielded part of the building very effectively in 1918, when the Choir and Transept escaped serious damage. Most of the fine 13th century stained-glass windows were removed in 1915 to a place of safety. They were originally taken from the church of Saint-Yved-de-Braines and inserted during the 19th century in the high windows of the apse and those of the Lady Chapel.