intersection of two or more vaults--is necessary to the complete development of the vaulting system; and for this the Romance architecture in which Mr. Richardson preferred to work, and which in a general way may be called the style of his design for Albany, does not provide.[E] The churches of the Provençal Romanesque were vaulted, but with a continuous tunnel vault, supported equally at all points, and demanding an enormous thickness of wall, pierced by few and small openings, to withstand the lateral thrust of the arch. The introduction of groined vaults involved a concentration of the supports and of the counterforts--that is to say, a series of buttresses in place of a continuous wall. The piers of the nave and the exterior buttresses, connected by flying buttresses with the vaults the thrust of which they withstood, thus constituted the framework of the building, and the wall between the buttresses became a mere screen, as finally it did become an avowed screen of painted glass. The history of this development of the vault is the history of the transition from Romanesque to Gothic architecture. The mediæval architects carried this development to its extreme, leaving at last, as in the Sainte Chapelle, no wall at all, and their work has been described as an attempt to “etherealize matter.” It may very well be doubted whether the architect of a modern cathedral should not stop short of the result they reached, and strive for a simpler and more robust treatment than theirs--in other words, for a treatment more Romanesque. But if we assume that the cathedral shall be ceiled in material as durable and monumental as that of its walls, we cannot reject the labors of the generations of artistic builders who concerned themselves with that problem, and attained so brilliant a solution of it. To take the instance before us, the clere-story of the nave and of the choir is in effect a continuous arcade of narrow-pointed lancets. It needs a second glance to note that they are grouped in pairs, and that the piers between the pairs are slightly broader than the piers dividing the openings of each pair. The slight increase in mass quite suffices to account in the interior for the principal roof timber which rests upon it, and, with the vaulting-shaft, to continue upward the line of the nave-pier. But if the flying buttress, necessary to transfer the thrust of the vault, were built at this point, the arcade of the exterior would be effectually interrupted, and the space between the buttresses set off into a single bay, as in the wall of the aisle below, which does, in fact, represent a vault. In that case a single large opening would naturally take the place of the pair of lancets, still further emphasizing the division into bays, and the side of the nave would at once bear a much stronger resemblance than it now bears to the accepted type of a cathedral. In the choir a like result would follow, and it would be emphasized at the east end. The circle of