44. RHEIMS CATHEDRAL. PLAN
The perils inherent in such a system are more apparent at Rheims than elsewhere, because of the colossal proportions of the building. The arrangement of the flying buttresses, however, is more logical than at Laon, Paris, Sens, and Bourges, by reason of the quadripartite arrangement of the main vault. The thrusts being equally distributed among the supporting piers, each flying buttress performs an identical office; their equal strength and solidity is therefore perfectly appropriate and logical. But though theoretically correct in its disposition of flying buttresses of equal strength to meet thrusts of equal strength, the method is vitiated by its inherent weakness as a system of abutment. The fragility of the flying buttress exposed it to two grave dangers, active and passive; active, taking into account the constant strain upon it as an abutment; passive, in regard to the gradual reduction of its solidity by exposure to weather. In support of this statement, it is only necessary to refer to the restorations which it has been found necessary to make within the last few years, to preserve the nave. The flying buttresses have been strengthened from below, a proceeding without which the collapse of the huge building would have been inevitable.
But we shall find much to call for unqualified admiration at Rheims in the grandiose conception of the work and in its powerful execution, in the magnificent arrangement of its eastern façade, and in the perfect harmony of the ornamentation, where sculpture, capitals, friezes, crockets, and floriations are so many types of mediæval decorative art at its best.
The Cathedral of Amiens, which dates from about 1220, and is one of the largest as well as one of the most admired of Gothic masterpieces, is directly founded upon that of Rheims. The plan is on the same lines, with this exception, that at Amiens the choir is of greater importance relatively to the nave, and that the piers and points of support are weaker and much more lofty.
45. RHEIMS CATHEDRAL. SECTION OF THE NAVE
46. RHEIMS CATHEDRAL. FLYING BUTTRESSES OF THE CHOIR
The Rémois architects, while exercised by the problems of equilibrium which their system involved, sought to minimise its dangers, which they recognised no less fully than their predecessors, by prudently avoiding all false bearings. It will be easily seen by a comparison of the two sections (Figs. 45 and 48) that the builders of Amiens were troubled by no such misgivings, or that they were at least more venturesome if not more accomplished. They did not hesitate to base the columns which received the crowns of the flying buttresses on a corbel arrangement which had no solid bearing, as may be seen by following the direction of the dotted line X in [Fig. 48]. The boldness, or rather the imprudence of such
an arrangement is patent, for the failure of anyone of the courses, or the decay of any part of the pier into which the corbels are keyed, would necessarily involve a rupture in the flying buttresses, on which the stability of the main vault depends. The disintegration of the whole building and its total ruin could be the only result. The perils of such combinations, or rather such tours de force of equilibrium, are exemplified at Beauvais. The architects who built the choir, about the year 1225, basing it on that of Amiens, determined to raise a monument which should surpass, both in plan and elevation, all the structures of their epoch. They increased the breadth of the choir and of its bays, raising, in the latter, intermediate piers on the crowns of the lower archivolts, thus dividing the upper bays, and at the same time strengthening the vault by auxiliary transverse arches. They exaggerated the height of the archivolts and of the large windows, and diminished their thickness, in order to give greater elegance and lightness, and the main vault rose to a height of more than 160 feet above the ground level. This tremendous elevation, the exaggeration of which in proportion to the width of the nave is striking, necessitated a complicated system of flying buttresses surpassing in boldness all that had gone before. The section in [Fig. 51] will give some idea of what has been justly described as an architectural folly. It is astonishing that the structure should have stood as it has done, taking into account the false bearings of the intermediate piers, here again shown by the dotted line X ([Fig. 51]).