are not usually pierced by many or large lights
(Fig. 180); and when there is a central feature, as a tower, or even a
dome, little or no light is introduced through it. On the other hand,
the Byzantine churches depend largely for light upon the ring of
windows which commonly encircles the base of the central dome, and
sometimes that of the subsidiary domes; and the gables are pierced
so as to supply any additional light required, so that windows are
infrequent in the lower walls. Broadly speaking, therefore, the
Western churches have side-lighting and the Eastern top-lighting.

[Illustration: FIG. 180.--CHURCH AT ROSHEIM. UPPER PORTION OF
FACADE.]

The great arches which carry the main domes form a notable feature in
Eastern churches, and are of very bold construction. In the basilican
churches one great arch, called "the arch of triumph," occurs, and
only one; this gives access to the apse: and a similar arch, which we
now denominate "the chancel arch," usually occupies a corresponding
position in all Romanesque churches. The arches of the arcade
separating the nave from the aisles in all Western churches are
usually of moderate span. In some ancient basilicas these arches are
replaced by a horizontal beam.

_The Columns._--In basilicas these were of antique type; very often
they had actually been obtained by the demolition of older buildings,
and when made purposely they were as a rule of the same general
character. The same might be said of those introduced into Byzantine
buildings, though a divergence from the classic type soon manifested
itself, and small columns began to appear as decorative features. In
Romanesque buildings the columns are very varied indeed, and shafts
are frequently introduced into the decoration of other features. They
occur in the jambs of doorways with mouldings or sub-arches springing
from them; long shafts and short ones, frequently supporting
ornamental arcades, are employed both internally and externally; and
altogether that use of the column as a means of decoration, of which
Gothic architecture presents so many examples, first began in the
Romanesque style.

The capitals employed in Romanesque buildings generally depart
considerably from the classic type, being based on the primitive cube
capital (Fig. 181), but, as a rule, in Eastern as well as in basilican
churches, they bear a tolerably close resemblance to classic ones.

[Illustration: FIG. 181.--CUBIC CAPITAL.]