It is evident that the roof of the side aisles, in order properly to abut the central vault, had to be carried up to a considerable height. This height being more than was necessary in the aisles, is sometimes divided into two storys, the upper one forming a gallery—an arrangement which was frequently adopted in Lombardy and the Rhineland, and also, as we have seen, in the Syrian churches above referred to. One great objection to the Provençal system of vaulting is that the churches are very dark—a clerestory being obviously impossible consistently with safety. Numerous expedients were adopted to provide more light, such as by introducing windows in the gables, and by heightening the side walls so as to admit of a small clerestory over the roof of the aisles. But the latter was found to be a very unsafe course, and at the best only clerestory windows of very small size could be introduced, so that the long barrel vaults still remained dark and gloomy.

In Aquitaine an entirely different system of vaulting was accidentally introduced, and threatened at one time to spread itself over the whole of Southern Gaul. The story of the importation of this style, and the various modifications arising out of it, is somewhat strange and remarkable. Owing to the pirates who infested the Straits of Gibraltar, the trade from the Levant with the West of France and Britain, was carried on by means of caravans, which conveyed the goods across the country, from the Mediterranean to the Bay of Biscay. The goods landed at Marseilles or Narbonne were thus carried by Limoges to La Rochelle and Nantes, where they were again shipped for the North of France and Britain. The town of Perigueux, situated in the centre of Aquitaine, at that time probably the richest country in Gaul, became the head-quarters of the Venetian merchants, by whom this traffic was chiefly carried on. These Venetians, as they had in the tenth century imported the plan and decorations of St Mark’s at Venice, from the East, so they soon afterwards resolved to carry the same model with them into Aquitaine. At Perigueux they erected a church exactly after the plan of St Mark’s, being in the form of a Greek cross, crowned with one dome over the central crossing, and four domes over the four arms of the cross. The general idea of this church of St Front at Perigueux is undoubtedly borrowed from St Mark’s, but the execution seems to have been entrusted to a native artist; for, although the conception is Eastern, the style of workmanship, is that of the locality. In the original the arches and domes are spherical, while here they are polygonal and pointed, which we have seen was the Provençal system of construction. The pendentives which fill up the angles under the domes are rudely executed in horizontal corbelling, not dressed as portions of a spherical vault, as they would have been by a scientific Eastern architect.

The church of St Front at Perigueux had great influence on the subsequent architecture of Aquitaine and the West of France. The plan of St Mark’s was not followed in other examples, the old traditional basilican plan being preferred and adhered to; but the dome raised upon pendentives, as introduced at St Front, became the common form of vaulting in Aquitaine and the West of France in the eleventh and twelfth centuries. In the churches thus constructed the side aisles are frequently omitted, and the building consists of a single hall, roofed with a series of domes resting on transverse arches, which are abutted with large internal buttresses. We thus find in Aquitaine and the South generally two important derivations from St Front, viz., 1st, the domed system of vaulting, and 2nd, the single or aisleless nave,—the latter being sometimes vaulted with domes and sometimes with groined arches. As late as the thirteenth century the influence of the dome made itself felt in the churches of Aquitaine, Poitou, and Anjou; while the influence of the plan of the single aisleless nave continued to be prominent in the churches of Languedoc long after the dome was abandoned, and even after the Gothic of the North had invaded the Southern provinces.

It thus happens that early churches such as the Cathedrals at Toulouse ([Fig. 34]) and Fréjus (see [Part VI.]) present a mixture of these ideas, being sometimes found designed on the plan of the aisleless hall, but at the same time roofed with groined vaulting. The buttresses in all these single nave churches are frequently internal, and form deep recesses, which are utilised as side chapels.

At a distance from Perigueux as a centre, domes are sometimes used, as is the case, for instance, in Auvergne, but in Provence the dome is generally limited to the space over the crossing.

In the latter locality the Byzantine influence exhibits itself in a different direction, being chiefly confined to details and subordinate features. But here another factor comes into play. The presence of the Roman monuments still existing in Provence has evidently tended to impress a Roman character on the architecture of the district. So strikingly indeed does some of the Provençal architecture resemble Roman work, both in general design and detail, that it has frequently been maintained that it is actually the work of the Lower Empire.

The style of Provence in the twelfth century differs on this account considerably from that of the other Romanesque styles. The revival which took place all over Europe in the eleventh and twelfth centuries occurred in Provence also, but the result there was somewhat peculiar, the effect of the Roman remains being to produce in many of the features of Provençal architecture a closer resemblance to the Romanesque style of Rome and Italy than to that of the Rhineland and the North.

FIG. 34. TOULOUSE CATHEDRAL.