Gardner, Helen: Art through the ages: an introduction to its history and significance (London: G. Bell and Sons, Ltd., 1927)

140

ROMAN PERIOD

gives us some conception o£ the great extent of these baths and
also of the orderly planning that characterizes the organization
of the parts.2 Pl. 52. b reconstructs one hall of the Baths of
Caracalla. The impression is of vast spaciousness and, in the rich


Fig. 73. A. Barrel vault. B. Groin vault seen from above. C. Groin vault seen
from below.

marble facings, carvings, and coffered ceilings, of magnificence
and splendor. The technical problem here involved was how to
enclose and roof over a vast space, to give it proper illumination
and still to keep the space open and free of the columns that would
be necessary were
a flat roof used, as
in the hypostyle
halls of Egypt (Pl.
11). We have seen
the predilection of
the Roman for the
arch. Given the
problem of roofing
over a rectangular
room by the sim-
plest arch system,
the result will be a
barrel vault (Fig.
73 a) which is, in
essence, a succes-
sion of arches
joined together,
resting directly up-
on the side walls, which must be thick enough to support the
weight. This can be made of stone or brick masonry, or of con-
crete by building up a temporary wooden framework known as

Fig. 74. A. Basilica of Maxentius or Constantine.
Rome. 106-112. a.d. Section of a reconstruction.


2 For the influence of the Roman baths, in plan, upon the Bank of England, see Bailey, Legacy
of Rome, p. 405. The Pennsylvania Station in New York shows their influence in general design
and spaciousness, though not in structural principle.