ROMANESQUE ARCHITECTURE IN EUROPE. 223 produced a new art founded on the old. This explains the birth of Romanesque, for on the collapse of the Western Roman Empire, the quarry of the ruins of ancient buildings largely influenced the work done, both in construction and decorative treatment, for the earlier buildings of the period were often built from the remains of ancient Roman buildings in the vicinity. In the course of time, however, a new style was evolved, for, putting aside spasmodic efforts, the period of the tenth to the twelfth centuries is remarkable for the tentative employment of a new constructive principle and a new use of material. The first was the principle of equilibrium which succeeded that of inert stability as used by the Romans, and the second was the employ- ment of dressed stonework in comparatively small pieces, con- nected with mortar beds of considerable thickness. This was a method not before attempted, because the materials in use up to that time had not demanded it. By this new employment of materials, the whole current of architecture was turned to a constructive system which should answer to its needs, and which, after many tentative experiments, was to lead to the next glorious period of architecture — the thirteenth century — in which elasticity of structure was joined to the principle of equilibrium. In Italy (page 228) there were various early Christian edifices erected at Ravenna from the fifth to the seventh centuries, for Ravenna was the principal city in Italy during this period, being the seat of the Exarch or representative of the Byzantine Emperor in the western part of his dominions. These buildings partake, naturally, of the elements of the fully developed Byzantine style, in the same way in which S. Mark, Venice, and S. Front, Perigueux, was the result of the close connection of these centres with the trade and commerce of the East (No. 84). In France (page 246), especially in the Western and Northern Provinces, the old traditional basilican plan was preferred and adhered to during the eleventh and twelfth centuries, with certain exceptions, notably S. Front, but the dome raised on pendentives became the common kind of vaulting, in the South, in conjunction with the aisleless nave. It is worthy of note also that the use of the pointed arch occurred in the South of France sooner than in the North, and it is considered by some, but with apparently little foundation, to have been derived from contact with the Saracens, who invaded this portion of France from 719-732. Further, the development of monasteries in the eleventh century gave a great impulse to civilization and agriculture, and exercised considerable influence on architecture. Provence was, moreover, in the twelfth and thirteenth centuries the chief centre of the growing traffic from the East, and the highway by which artistic and other products of the Levant were dispersed through France and the North of Europe. Similarly, the development from Roman to Gothic art was
