This issue’s limited edition print is of a Ladd P. Ehlinger sketch of S. Vitale in Ravenna, Italy. This church is archetypal and a paradigm of centripetal plan churches that were developed during the Byzantine empire during the reign of the Emperor Justinian and his Empress Theodora. S. Vitale was commissioned by the Episcopate of Ecclesius about the same time as S. Sergius and S. Bacchus were in Constantinople (present day Istanbul) in 526 AD, and was completed in 547 AD. It is hard to fathom that this church is almost 1,500 years old, yet looks like it was built maybe twenty years ago.
Centripetal plan churches were a radical departure from the original Christian basilican plan churches. Basilican plan churches were an adaptation of the Roman Basilica, a building type devoted to legal and public affairs. When used by the Romans, the rectilinear plan was entered from the middle of the long side. The entry was changed to the middle of the short side when the building form was adapted as a church and the length of the rectangle was lengthened as well to emphasize the processional aspect of one’s spiritual journey through processional rituals associated with Mass and other services such as Stations of the Cross.
In the centripetal plan churches, the emphasis shifted to expression of the unity and oneness of the spirit of all beings and of God, and architectural forms were sought to express that. This began at first in the eastern rite churches, where the emphasis today is still predominately centripetal plan churches. Square plans, round plans, octagonal plans (the next best thing to a circle) were incorporated with domes providing the roof enclosure to complete the space and emphasize the central focus that is in harmony with the unity of God.
S. Vitale has an inner octagon of 52' span and an outer octagon of 115' with an apsidal chancel for the main altar opening off one of the eight bays, while the other seven have apsidal shapes formed by columns to give an undulation and feeling of expansive movement to the central space. This is a precursor to the Baroque movement in architecture. The lower columns support the second level gallery while the upper columns support what are called squinches that meld the walls into the circle required for the drum and dome it supports in turn. The dome is unique in that it is constructed of fired clay pots nested one into the other and laid horizontally in the upper part to lighten the structure. The dome is roofed over with a timber roof unlike what the Romans did, that presages this medieval practice.
The interior is very rich and sculptural in the carvings of the capitals and other components, and dazzling in the array of polished marble, granite, and precious metals. This is in stark contrast to the almost barren, plain and unadorned exterior treatment. The only decorative elements on the exterior are the main doorway and the top of the campanile (bell tower).
The vacillation between centripetal plan churches and basilican or processional plan churches continues today in the design community and in the various religious communities. It really does depend upon the orientation of the congregation: spiritual processional journey or spiritual unity.
Ladd P. Ehlinger AIA