The similarity of the form of this church to the Roman basilicas will be evident on referring to the representations of those buildings, more especially to that of San Vincenzo alle Tre Fontane (Woodcut No. 408), though the details have nothing in common except in the use of flat tiles between the cornices of the arches, which is singularly characteristic of Roman masonry. The points in which this example is most evidently the source of some of the important peculiarities of the true Gothic, are the subordination of the side-aisles to the central one, and the perfectly developed clerestory. These are not found in any of the styles of France hitherto described. Eventually, as we shall shortly see, stone became the material used in the interior ceiling of Gothic vaults, but protected externally by a wooden roof. This stone vault was not, I believe, attempted in France before the 11th century. In the meanwhile, wooden-roofed churches, like that at Beauvais, seem to have been usual and prevalent all over the North of France, though, as may be supposed, both from the smallness of their dimensions and the perishable nature of their materials, most of them, have been either superseded by larger structures, or have been destroyed by fire or by the accidents of time. M. Woillez describes five or six as existing still in the diocese of Beauvais, and varying in age from the 6th or 7th century, which probably is the date of the Basse Œuvre, to the beginning of the 11th century; and if other districts were carefully examined, more examples would probably be found. Normandy must perhaps be excepted, for there the rude Northmen seem first to have destroyed all the churches, and then to have rebuilt them with a magnificence they did not previously possess. Churches of the same class, or others at least extremely similar to them, as far as we can judge from such representations as have been published, exist even beyond the Loire. There is one at Savonières in Anjou, and a still more curious one at St. Généreux in Vienne, not far from Poitiers, which shows in great perfection a style of decoration by triangular pediments and a peculiar sort of mosaic in brickwork. [Illustration: 609. Decoration of St. Généreux. (From Gailhabaud.)] The same style of decoration is carried out in the old church of St. Jean at Poitiers, which probably is even older than the Basse Œuvre of Beauvais. The old church, which now forms the ante-church to St. Front at Périgueux (Woodcut No. 562), seems also to belong to the same class; but, if M. Félix de Verneilh’s restoration is to be trusted, it approaches nearer to a Romanesque style than any other of its class, of which it may nevertheless possibly be the most southern example.