on of the structure This will be taken up later.

Ravenna Capitals.

With the reign of Constantine, and the introduction of Christianity as
the acknowledged religion of Rome, Byzantine art, as such, made its
appearance. The culture of Rome was transferred to Byzantium, henceforth
to be known as Constantinople. Governed alternately by Greek and by
Persian, it had received a strong Oriental character from the Eastern
nations, and had added to the Greek subtlety and delicacy of expression
the Oriental love of detail. When converted by Constantine into New
Rome, it became a perfect treasure house of Eastern and Grecian art. The
Byzantine work, which spread over the East in the sixth, seventh, and
eighth centuries, is therefore a union of the refinement of the Greek,
the desire for color and detail of the Oriental, and the vigor of
constructional invention and conception of mass and grandeur of the
Roman. A portion of it was transplanted to Ravenna during Justinian's
reign, and there is a glorious afterglow in the Venetian splendor of the
tenth and eleventh centuries. The three great centres of Byzantine art
work are Constantinople, Ravenna, and Venice; and the three most noted
examples, the churches of Sta. Sophia, S. Vitale, and St. Mark's. Apart
from these, the cathedral at Monreale, and the Capella Palatina in
Palermo, Sicily, represent a variation from the Byzantine type affected
by Moslem design.

From the time of Constantine to that of Justinian, one hundred and fifty
years, is a period of formation. Under the reign of Justinian, Byzantine
art reached its height. Prominent among its factors is the use of
mosaic, the influence of which spread insidiously through its whole
system, until in the later work the cornices and entablatures of classic
design withered into long thin lines of moulding; projections which
disturbed the effect of color by the shadows they cast were discarded;
voussoirs disappeared under a mosaic veil; surfaces resolved themselves
into broad expanses of infinitely varied tones, bounded by narrow but
strongly contrasting bands and borders of marble. All ornament had
resolved itself into surface decoration, or as nearly that as possible.

In 539 Belisarius took Ravenna in the name of the Emperor Justinian, and
to celebrate this event Justinian decided to erect a magnificent
monument in the city. He chose to replace, by a more important
structure, the small church dedicated to S. Vitale, and