of that time remains, they are, and contain in themselves, the most
important monuments that exist of the Christian history of Rome for all
that long period.


[Footnote C: For instance, about the middle of the fourth century, St.
Julius, then Pope, is said to have begun three. See Marchi's _Momumenti
delle Arti Cristiane_, p. 82.]

It has been much the fashion during the last two centuries, among a
certain class of critics hostile to the Roman Church, and sometimes
hostile to Christianity, to endeavor to throw doubts on the fact of
this immense amount of underground work having been accomplished by the
Christians. It has been said that the catacombs were in part the work of
the heathen, and that the Christians made use of excavations which they
found ready to their hand. Such and other similar assertions have been
put forward with great confidence; but there is one overwhelming
and complete answer to all such doubts,--a visit to the catacombs
themselves. No skepticism can stand against such arguments as are
presented there. Every pathway is distinctly the work of Christian
hands; the whole subterranean city is filled with a host of the
Christian dead. But there are other convincing proofs of the character
of their makers. These are of a curiously simple description, and are
due chiefly to the investigations of late years. Nine tenths of the
catacombs now known are cut through one of the volcanic rocks which
abound in the neighborhood of Rome. Of the three chief varieties of
volcanic rock that exist there, this is the only one which is of little
use for purposes of art or trade. It could not have been quarried for
profit. It would not have been quarried, therefore, by the Romans,
except for the purposes of burial,--and the only inscriptions and other