teps above the presbytery. To the right and left
the seats of the cardinals followed the line of the apse. At the centre of
the chord stood the high altar beneath a ciborium, resting on four pillars
of porphyry. Beneath the altar was the subterranean chapel, the centre of
the devotion of so large a portion of the Christian world, believed to
contain the remains of St Peter; a vaulted crypt ran round the foundation
wall of the apse in which many of the popes were buried. The roof showed
its naked beams and rafters.

[Illustration: FIG. 11.--Sectional view of the old Basilica of St Peter,
before its destruction in the 16th century.]

[Illustration: FIG. 12.--Ground-Plan of St Paul's, Rome, before its
destruction by fire.

_a_, Narthex. _b_, Nave. _c_, _c_, Side aisles. _d_, Altar. _e_, Bema. _f_,
Apse.]

The basilica of St Paul without the walls, dedicated 324 A.D., rebuilt
388-423, remained in a sadly neglected state, but substantially unaltered,
till the disastrous fire of 1823, which reduced the nave to a calcined
ruin. Its plan and dimensions (figs. 12, 13) were almost identical with
those of St Peter's.

The only parts of the modernized five-aisled basilica of St John Lateran
(of which we have a plan in its original state, Agincourt, pl. lxxiii. No.
22) which retain any interest, are the double-vaulted aisle which runs
round the apse, a most unusual arrangement, and the baptistery. The latter
is an octagonal building standing some little distance from the basilica to
the south. Its roof is supported by a double range of columns, one above
the other, encircling the baptismal basin sunk below the floor.

Of the three-aisled basilicas the best example is the Liberian or S. Maria
Maggiore dedicated 365, and reconstructed 432 A.D. Its internal length to
the chord of the apse is 250 ft. by 100 ft. in breadth. The Ionic pillars
of grey granite, uniform in style, twenty on each side, form a colonnade of
great dignity and beauty, unfortunately broken towards the east by
intrusive arches opening into chapels. The clerestory, though modern, is
excellent in style and arrangement. Corinthian pilasters divide the
windows, beneath which are very remarkable mosaic pictures of subjects from
Old Testament history, generally supposed to [v.03 p.0475] date from the
pontificate of Sixtus III., 432-440. The face of the arch of triumph
presents also a series of mosaics illustrative of the infancy of our Lord,
of great value in the hi