On the contrary, the tendency of all modern discoveries has been in the opposite direction. Now that we have learnt to distinguish one part of a cemetery from another, and to trace the several periods of their excavation in chronological order, it has been made clear that each several part was originally a separate _area_ as well defined as that of any Pagan monument, and its limits, like theirs, were determined by the course of the adjacent road, and walls of enclosure built for the purpose. We find, for example, that what is now called the Catacomb of St. Callixtus, is made up of eight or ten such _areæ_, each with its own staircase, and its own system of excavation, conducted with order and economy. The _area_ that was first used here for purposes of Christian burial measured 250 Roman feet by 100, and its galleries were reached by two staircases, entering boldly from the surface, within sight of all passers-by along the Appian Way, and going straight to their point. By and by, a second _area_ was added of the same dimensions; and in process of time, a third, 150 feet by 125; a fourth, of the same dimensions, and so on. [Illustration: _Entrance to a most Ancient Christian Sepulchre at Tor Marancia._] The internal arrangements of some of these _areæ_ have undergone so much change in the course of centuries, that it is no longer possible to recover the precise form of their original entrances. But what is not found in one place is found in another; and one of the recent discoveries has been the entrance to a famous catacomb on the Via Ardeatina, not far from the cemetery of which we have just been speaking It is cut in the side of a hill close to the highway and has a front of very fine brickwork, with a cornice of terra-cotta, and the usual space for an inscription, which has now unfortunately perished. The sepulchre to which it introduces us is ornamented with Christian paintings of a very classical character; and it may be considered as proved that it once belonged to the Flavian family,—that imperial family which gave Vespasian to the throne, and (as we learn even from Pagan authors) gave a martyr and several confessors to the Christian Church. The cemetery was begun in the days of Domitian, _i.e._, towards the end of the first century, and it is known by the name of his relative, St. Domitilla, on whose property (there is good reason to believe) it was excavated. The entrance is flanked on either side by a chamber, built of brick subsequently to the excavation of the subterranean sepulchre. The larger of these chambers, with the bench running all the way round it, was evidently the place of meeting for those whose duty or privilege it was to assemble here on the appointed anniversaries to do honour to the deceased; the smaller space, on the left, with its well and cistern, and fragments of a staircase, was no less obviously occupied by the dwelling-house of the _custode_, or guardian of the monument.