We do not know who was the original architect of _la Gatienne_. Étienne de Mortagne, who designed the Benedictine church at Marmoutier, is mentioned, in 1269, as master-of-works at the cathedral, but by that time its choir was completed. That choir, while making no pretense of being sublime, is a monument of noble robustness, displaying within and without the veriest genius of good taste. The vista closing the eastern end of the church is one of the most satisfactory in France, owing to its right proportion. In this, Tours derives directly from Amiens. Its pier arcade comprises one-third of the interior wall elevation; and the triforium and clearstory make up the other two-thirds--clearstory being double the height of triforium. At Tours the relation of span and height is admirable, and both are well correlated with length. Seen in perspective down the nave, the three stories of colored glass around the sanctuary are the supreme impression of this church interior, and seldom does one pass from its west portal without turning back for a lingering look at that harmonious chevet of consecrated light. Through the pier arches can be seen symmetrically the windows of the apse chapels. The design of the glazed triforium is excelled by no other in France; though serving as a kind of pedestal for the upper lights, it retains its own entity. When the choir of Tours was completed, the builders proceeded at once to erect the transept which, the stones themselves say, must have been finished as the XIII century closed. The nave's easternmost bays touching it belong to the first years of the next century, as do the two rose windows of the transept. The northern rose is irreproachable in design and of the same scintillating jewel tradition as XIII-century glass. The Hundred Years' War, here as elsewhere, checked building activities. When they were resumed at Tours, happily the first plans were adhered to, so that choir and nave are homogeneous. As the church advanced toward the west, the window tracery changed from Rayonnant to Flamboyant, the profiles grew prismatic, and the sculpture of the capitals became naturalistic rather than an architectural interpretation of foliage. The nave was made narrower than the choir, probably with the intention of joining it to the XII-century façade. Of the four triumphal piers at the transept-crossing, the two westernmost ones stand closer together than those flanking the choir, whose spacious procession path causes the side aisles of the nave to appear meager.