Gardners Art through the Ages A Global History

The diverse vistas and screenlike ornamented surfaces mask the
structural lines. The columnar arcades of the nave and second-story
galleries have no real structural function. Like the walls they pierce,
they are only part of a fragile “fill” between the huge piers. Struc-
turally, although Hagia Sophia may seem Roman in its great scale
and majesty, it does not have Roman organization of its masses. The
very fact that the “walls” in Hagia Sophia are actually concealed (and
barely adequate) piers indicates that the architects sought Roman
monumentality as an effect and did not design the building accord-
ing to Roman principles. Using brick in place of concrete marked a
further departure from Roman practice and characterizes Byzantine
architecture as a distinctive structural style. Hagia Sophia’s eight
great supporting piers are ashlar masonry, but the screen walls are
brick, as are the vaults of the aisles and galleries and the dome and
semicircular half-domes.
The ingenious design of Hagia Sophia provided the illumination
and the setting for the solemn liturgy of the Orthodox faith. Through
the large windows along the rim of the great dome, light poured
down upon the interior’s jeweled splendor, where priests staged the
sacred spectacle. Sung by clerical choirs, the Orthodox equivalent of
the Latin Mass celebrated the sacrament of the Eucharist at the altar
in the apsidal sanctuary, in spiritual reenactment of Jesus’ Crucifix-
ion. Processions of chanting priests, accompanying the patriarch
(archbishop) of Constantinople, moved slowly to and from the sanc-
tuary and the vast nave. The gorgeous array of their vestments rivaled
the interior’s polychrome marbles; finely wrought, gleaming candle-
sticks and candelabra; the illuminated books bound in gold or ivory
and inlaid with jewels and enamels; and the crosses, sacred vessels,

and processional banners. Each feature, with its great richness of tex-

ture and color, glowing in shafts of light from the dome, contributed

to the majestic ambience of Justinian’s great church.

The nave of Hagia Sophia was reserved for the clergy. The laity,

segregated by sex, were confined to the shadows of the aisles and gal-

leries, restrained in most places by marble parapets. The complex

spatial arrangement allowed only partial views of the brilliant cere-

mony. The emperor was the only layperson privileged to enter the

sanctuary. When he participated with the patriarch in the liturgical

drama, standing at the pulpit beneath the great dome, his rule was

again sanctified and his person exalted. Church and state were sym-

bolically made one. The church building was then the earthly image

of the court of Heaven, its light the image of God and God’s holy

wisdom.

At Hagia Sophia, the intricate logic of Greek theology, the am-

bitious scale of Rome, the vaulting tradition of the Near East, and

the mysticism of Eastern Christianity combined to create a monu-

ment that is at once a summation of antiquity and a positive asser-

tion of the triumph of Christian faith.

RAVENNAIn 493, Theodoric, the Ostrogoths’ greatest king,

chose the Italian city of Ravenna as the capital of his kingdom, which

encompassed much of the Balkans and all of Italy (see Chapter 11).

During the short history of Theodoric’s unfortunate successors, the

importance of the city declined. But in 539, Justinian’s general Beli-

sarius captured Ravenna, initiating the third and most important

stage of the city’s history. Ravenna remained the Eastern Roman

Empire’s foothold in Italy for two centuries, until the Lombards and

Early Byzantine Art 315

P

erhaps the most characteristic feature of Byzantine architecture
is the placement of a dome, which is circular at its base, over
a square, as in the Justinianic church of Hagia Sophia (FIGS. 12-2to
12-4) and countless later structures (for example,FIGS. 12-22and
12-24). Two structural devices that are hallmarks of Byzantine engi-
neering made this feat possible:pendentives and squinches.
In pendentive construction (from the Latin pendere,“to hang”) a
dome rests on what is, in effect, a second, larger dome (FIG. 12-5,left).
The top portion and four segments around the rim of the larger dome
are omitted so that four curved triangles, or pendentives, are formed.
The pendentives join to form a ring and four arches whose planes
bound a square. The weight of the dome is thus transferred not to the
walls but rather through the pendentives and arches to the four piers
from which the arches spring. The first use of pendentives on a monu-
mental scale was in Hagia Sophia (FIG. 12-4) in the mid-sixth century,
although Near Eastern architects had experimented with them earlier.
In Roman and Early Christian central-plan buildings, such as the Pan-
theon (FIGS. 10-50and 10-51) and Santa Costanza (FIG. 11-11), the
domes spring directly from the circular top of a cylinder (FIG. 10-6d).
The pendentive system is a dynamic solution to the problem of
setting a round dome over a square. The device made possible a
union of centralized and longitudinal or basilican structures. A sim-
ilar effect can be achieved using squinches (FIG. 12-5,right)—arches,
corbels, or lintels—that bridge the corners of the supporting walls

and form an octagon inscribed within a square (FIG. 12-22). To

achieve even greater height, a builder can rest a dome on a cylindri-

cal drum that in turn rests on either pendentives or squinches, but

the principle of supporting a dome over a square is the same.

Pendentives and Squinches

ARCHITECTURAL BASICS

12-5Dome on pendentives (left) and on squinches (right).

Pendentives (triangular sections of a sphere) make it possible to place a

dome on a ring over a square. Squinches achieve the same goal by

bridging the corners of the square to form an octagonal base.

Pendentives Squinches