of private bath-rooms. The side and rear blocks
contained numerous halls and porticoes, the precise object of which
it is now very difficult to ascertain. As Byron says:

"Temples, baths, or halls?
Pronounce who can."

This belt of buildings surrounded an open courtyard or garden, in
which was placed the principal bathing establishment (Fig. 133), a
building 730 ft. by 380 ft., which contained the large piscina, or
swimming-bath, various hot baths, dressing-rooms, gymnasia, and other
halls for athletic exercises. In the centre of one of the longer sides
was a large semicircular projection, roofed with a dome, which was
lined with brass: this rotunda was called the solar cell. From the
ruins of these baths were taken some of the most splendid specimens of
antique sculpture, such as the Farnese Hercules and the Flora in the
Museum of Naples.

The baths of Diocletian, erected just at the commencement of the
fourth century A.D., were hardly inferior to those of Caracalla, but
modern and ancient buildings are now intermingled to such an extent
that the general plan of the buildings cannot now be traced with
accuracy. There are said to have been over 3000 marble seats in these
baths; the walls were covered with mosaics, and the columns were of
Egyptian granite and green Numidian marble. The Ephebeum, or grand
hall, still exists as the church of Santa Maria degli Angeli, having
been restored by Michelangelo. It is nearly 300 ft. long by 90 ft.
wide, and is roofed by three magnificent cross vaults, supported on
eight granite columns 45 ft. in height. (Fig. 134.)

There is one ancient building in Rome more impressive than any other,
not only because it is in a better state of preservation, but because
of the dignity with which it has been designed, the perfection with
which it has been constructed, and the effectiveness of the mode in
which its interior is lighted. We allude to the Pantheon. Opinions
differ as to whether this was a Hall attached to the thermae of
Agrippa, or whether it was a temple. Without attempting to determine
this point, we may at any rate claim that the interior of this
building admirably illustrates the boldness and telling power with
which the large halls forming part of the thermae were designed; and,
whether it belonged to such a building or not, it is wonderfully well
fitted to illustrate this subject.

[Illustration: FIG. 134.--INTERIOR OF SANTA MARIA DEGLI ANGELI,
ROME.]