Fig. 10.—Loches, Saint Ours.
elevation and side aisles which have now disappeared. Each nave bay is converted from a square into an octagon by flat triangular pendentives on very small trumpet arches. But instead of domes, the builders of Saint Ours substituted a hollow octagonal pyramid of stone over each bay. Such a system, while presenting the same aesthetic objection as that of Le Puy, had greater structural advantages. The pyramids could be built entirely without centering, and exerted almost no outward thrust, while the stones of which they were constructed could be faced on the exterior [(Fig. 9)] as well as the interior, and the steep roof thus formed provided adequate drainage for the rain and snow of the region.[34]
Tunnel Vaults
If the dome played but a small part in Romanesque architecture, such was not the case with the tunnel vault. Almost as old as civilization itself, this method of vaulting had been employed to a greater or less extent in every age from the Egyptian period to that of the Carolingian Empire. It is natural, therefore, to find it the principal method in use during the entire Romanesque era. Nor is it necessary to trace its history back to Persian or Armenian sources. The builders of the eleventh and subsequent centuries had plenty of examples nearer at hand. Roman vaults, some of them of stone, were still in a good state of preservation in many parts of the western world, and almost every country or province possessed examples dating from Carolingian days.[35] It is not the use of this roofing system, therefore, but the skill with which it was adapted to the naves and aisles of churches of basilical plan, that furnishes the most interesting features in the study of Romanesque tunnel vaulting. In fact, so distinct are the combinations and methods employed in different regions, that they constitute veritable architectural schools which may be classified and separately discussed.[36]