dream. No better
place could be chosen for the study of the next class of Roman places
of worship, which comprises:--

V. PAGAN MONUMENTS CONVERTED INTO CHURCHES. The experience gained in
twenty-five years of active exploration in ancient Rome, both above
and below ground, enables me to state that every pagan building which
was capable of giving shelter to a congregation was transformed, at
one time or another, into a church or a chapel. Smaller edifices, like
temples and mausoleums, were adapted bodily to their new office, while
the larger ones, such as thermae, theatres, circuses, and barracks were
occupied in parts only. Let not the student be deceived by the
appearance of ruins which seem to escape this rule; if he submits them
to a patient investigation, he will always discover traces of the
work of the Christians. How many times have I studied the so-called
Temple of the Sibyl at Tivoli without detecting the faint traces of
the figures of the Saviour and the four saints, which now appear to me
distinctly visible in the niche of the cella. And again, how many
times have I looked at the Temple of Neptune in the Piazza di
Pietra,[91] without noticing a tiny figure of Christ on the cross in
one of the flutings of the fourth column on the left. It seems to me
that, at one period, there must have been more churches than
habitations in Rome.

I shall ask the reader to walk over the Sacra Via from the foot of the
Temple of Claudius, on the ruins of which we are still sitting, to the
summit of the Capitol, and see what changes time has wrought on the
surroundings of this pathway of the gods.

The Coliseum, which we meet first, on our right, was bristling with
churches. There was one at the foot of the Colossus of the Sun, where
the bodies of the two Persian martyrs, Abdon and Sennen, were exposed
at the time of the persecution of Decius. There were four dedicated to
the Saviour (_S. Salvator in Tellure_, _de Trasi_, _de Insula_, _de
rota Colisei_), a sixth to S. James, a seventh to S. Agatha (_ad caput
Africae_), besides other chapels and oratories within the amphitheatre
itself.

Proceeding towards the Summa Sacra Via and the Arch of Titus we find a
church of S. Peter nestled in the ruins of the vestibule of the Temple
of Venus (the S. Maria Nova of later times).

Popular tradition connected this church with the alleged fall of Simon
the magician,--so vividly represented in Francesco Vanni's picture, in
the Vati