Circular Buildings.
One of the best known, as well as one of the largest examples of this class of buildings in Italy, is the baptistery at Pisa (seen partially on the left side of Woodcut No. [465]). Internally it is, as nearly as may be, 100 ft. in diameter, and the walls are about 8 ft. 6 in. in thickness. The dome itself, however, is only 60 ft. in diameter, and is supported on four piers and eight pillars. These serve to separate the central space from the aisle which runs round it, and which is two storeys in height, but singularly ill-proportioned and clumsy in detail. The worst part of the design, however, is the dome, if dome it can be called. Internally it is conical in form, and thrust through an external hemispherical dome in a manner more clumsy and unpleasing than any other example of its class. Externally, these defects are to some extent atoned for by considerable richness and beauty of detail. It had originally only one range of blind arcades, with three-quarter columns, surmounted by an open arcade; an arrangement exactly similar to that of the two lower storeys of the cathedral and the leaning tower (Woodcut No. [488]). A considerable amount of pointed Gothic decoration was afterwards added, which, though somewhat incongruous, is elegant in itself, and hides to some extent the original defects of the design. But the outline of the building and its whole arrangements are so radically bad, that no amount of ornament can ever redeem them.
Taken altogether, the Pisan baptistery is so very peculiar, that it would be interesting if its design could be traced back to some undoubted original. That this is possible will hardly be doubted by any one at all familiar with the subject; meanwhile, the building most like it that has been illustrated is the little church of San Donato, at Zara. The church was probably built according to Mr. Jackson by Bishop Donatus III. at the beginning of the 9th century, with materials taken from ancient buildings, some of them of the best period of Roman architecture. The two monolithic columns in front of the triple sanctuary, and which are 30 ft. in height, bear testimony to the size and importance of the temple they originally adorned, and the great thickness of the walls and the size of the piers suggest a wealth of material at the disposal of the builders. The rectangular building on the south side Mr. Jackson considers to be coeval with the church; and the chamber over it, which was on the same level and originally opened on to the gallery round the aisles, formed a second church intended for the use of the catechumens. The church is so built round that it is impossible to say what its external appearance may have been. Both from its resemblance to the Pisan baptistery and its own merits, it is an interesting addition to our knowledge of those circular churches which were such favourites with all the Christian architects in the Carlovingian period. The resemblance in this instance is the more remarkable, because the façade of the cathedral at Zara (Woodcut No. [467]) is in the Pisan style, only slightly modified by local peculiarities. From what we already know, it seems undoubted that there was a close connection—architecturally, at least—between Pisa and Zara. If this were fully investigated, it would probably throw considerable light on the origin of the Pisan style, which has hitherto seemed so exceptional in Italy, and also explain how the Byzantine element came to be so strongly developed in what at first sight appears to be a Romanesque style of art.
486. Ground and Upper Storey of San Donato, Zara. (From Jackson.) Scale 100 ft. to 1 in.
487. Section San Donato, Zara. Scale 50 ft. to 1 in.