Nearly about the same time a circular building was erected hard by the church, designed as a mausoleum for Constantia and other members of the imperial family. The Mausoleum of Hadrian was occupied by the bodies of heathen emperors and empresses, and filled with heathen associations. New tombs were needed for the bodies of those who professed to have revolted from heathenism. The marble pillars of the Mausoleum of Constantia were taken from more ancient and nobler buildings, its walls were lined with mosaics, and her body was laid in a splendid sarcophagus of porphyry. In the thirteenth century, after Constantia had been received into the liberal community of Roman saints, her mausoleum was consecrated as a church and dedicated to her honor. A narrow, unworn path leads to it from the Church of St. Agnes; it has been long left uncared-for and unfrequented, and, stripped of its movable ornaments, it is now in a half-ruinous condition. But its decay is more impressive than the gaudy brightness of more admired and renovated buildings. The weeds that grow in the crevices of its pavement and hang over the capitals of its ancient pillars, the green mould on its walls, the cracks in its mosaics, are better and fuller of suggestion to the imagination than the shiny surface and the elaborate finish of modern restorations. Restoration in these days always implies irreverence and bad taste. But the architecture of this old building and the purpose for which it was originally designed present a marked example of the rapidity of the change in the character of the Christians with the change of their condition at Rome, during the reign of Constantine. The worldliness that follows close on prosperity undermined the spirit of faith; the pomp and luxury of the court and the palace were carried into the forms of worship, into the construction of churches, into the manner of burial. Social distinctions overcame the brotherhood in Christ. Riches paved an easy way into the next world, and power set up guards around it. Imperial remains were not to mingle with common dust, and the mausoleum of the princess rose above the rock-hewn and narrow grave of the martyr and saint.
The present descent into the catacombs that lie near the churches of St. Agnes and St. Constantia is by an entrance in a neighboring field, made, after the time of persecution, to accommodate those who might desire to visit the underground chapels and holy graves. A vast labyrinth of streets spreads in every direction from it. Many chambers have been cut in the rock at the side of the passages,—some for family burial-places, some for chapels, some for places of instruction for those not yet fully entered into the knowledge of the faith. It is one of the most populous of the subterranean cemeteries, and one of the most interesting, from the great variety in its examples of underground architectural construction, and from the number of the paintings that are found upon its walls. But its peculiar interest is, that it affords at one point a marked example of the connection of an arenarium, or pit from which pozzolana was extracted, with the streets of the cemetery itself. At this point, the bed of compact tufa, in which the graves are dug, degenerates into friable and loosely compacted volcanic sand,—and it was here, very probably, that the cemetery was begun, at a time when every precaution had to be used by the Christians to prevent the discovery of their burial-places. No other of the catacombs gives a clearer exhibition of the differences in construction resulting from the different objects of excavation. In the Acts known as those of St. Valentine it is related, that in the time of Claudius many Christians were condemned to work in certain sand-pits. Under cover of such opportunities, occasions might be found in which hidden graves could be formed in the neighboring harder soil. In digging out the sand, the object was to take out the greatest quantity consistent with safety, leaving only such supports as were necessary to hold up the superincumbent earth. There are few regular paths, but wide spaces with occasional piers,—the passages being of sufficient width to admit of the entrance of beasts of burden, and even of carts. The soil crumbles so easily, that no row of excavations one above another could be made in it; for the stroke of the pick-axe brings it down in loose masses. The whole aspect of the sand-pit contrasts strikingly with that of the catacombs, with their three-feet wide galleries, their perpendicular walls, and their tier on tier of graves.
The stratum of pozzolana at the Catacombs of St. Agnes overlies a portion of the more solid stratum of tufa, and the entrance to the sand-pit from the cemetery is by steps leading up from the end of a long gallery. Such an entrance could have been easily concealed; and the tufa cut out for the graves, after having been reduced to the condition of pozzolana, might easily at night have been brought up to the floor of the pit. In many of the Acts of the Martyrs it is said that they were buried in Arenario, "in the sand-pit,"—an expression which, there seems no good reason for doubting, meant in the catacombs whose entrance was at the sand-pit, they not having yet received a distinctive name.
It is difficult to convey to a distant reader even a small share of the interest with which one sees on the spot evidences of the reality of the precautions with which, in those early centuries, the Christians of Rome were forced to guard themselves against a persecution which extended to their very burial-places,—or even of the interest with which one walks through the unchanged paths dug out of the rock by this tenebrosa et lucifugax natio. In the midst of the obscurity of history and the fog of fable, here is the solid earth giving evidence of truth. Here one sees where, by the light of his dim candle, the solitary digger hollowed out the grave of one of the near followers of the apostles; and here one reads in hasty and ill-spelt inscriptions something of the affection and of the faith of those who buried their dead in the sepulchre dug in the rock. The Christian Rome underground is a rebuke to the Papal Rome above it; and, from the worldly pomp, the tedious forms, the trickeries, the mistakes, the false claims and falser assertions, the empty architecture that reveals the infidelity of its builders, the gross materialism, and the crass superstition of the Roman Church, one turns with relief of heart and eyes to the poverty and bareness of the dark and narrow catacombs, and to the simple piety of the words found upon their graves. In them is at once the exhibition and the promise of a purer Christianity. In them, indeed, one may see only too plainly the evidences of ignorance, the beginnings of superstitions, the first, traces of the corruption of the truth, the proofs of false zeal and of foolish martyrdoms,—but with these are also to be plainly seen the purity and the spirituality of elevated Christian faith.
In the service of the Roman Church used at the removal of the bodies of the holy martyrs from their graves in the catacombs is a prayer in which are the words,—"Thou hast set the bodies of thy soldiers as guards around the walls of this thy beloved Jerusalem";—and as one passes from catacomb to catacomb, it is, indeed, as if he passed from station to station of the encircling camp of the great army of the martyrs. Leaving the burial-place of St. Agnes, we continue along the Nomentan Way to the seventh milestone from Rome. Here the Campagna stretches on either side in broad, unsheltered sweeps. Now and then a rough wall crosses the fields, marking the boundaries of one of the great farms into which the land is divided. On the left stands a low farm-house, with its outlying buildings, and at a distance on each side the eye falls on low square brick towers of the Middle Ages, and on the ruinous heaps of more ancient tombs. The Sabine mountains push their feet far down upon the plain, covered with a gray-green garment of olive-woods. Few scenes in the Campagna are more striking, from the mingling of barrenness and beauty, from the absence of imposing monumental ruins and the presence of old associations. The turf of the wide fields was cropped in the winter by the herds driven down at that season from the recesses of the Neapolitan mountains, and the irregular surface of the soil afforded no special indications of treasures buried beneath it. But the Campagna is full of hidden graves and secreted buildings.
In the Acts of the Martyrdom of St. Alexander, who, according to the story of the Church, was the sixth successor of St. Peter, and who was put to death in the persecution of Trajan, in the year 117, it was said that his body was buried by a Roman lady, Severina, "on her farm, at the seventh milestone from Rome on the Nomentan Way." These Acts, however, were regarded as apocryphal, and their statement had drawn but little attention to the locality. In the spring of 1855, a Roman archaeologist, Signore Guidi, obtained permission from the Propaganda, by whom the land was now held, as a legacy from the last of the Stuarts, the Cardinal York, to make excavations upon it. Beginning at a short distance from the road, on the right hand, and proceeding carefully, he soon struck upon a flight of steps formed of pieces of broken marble, which, at about fifteen feet below the surface of the ground, ended upon a floor paved with bits of marble, tombstones, and mosaics. As the work proceeded, it disclosed the walls of an irregular church, that had been constructed, like that of St. Agnes, partially beneath the soil, for the purpose of affording an entrance into adjoining catacombs. Remains of the altar were found, and portions of the open-work marble screen which had stood before it over the crypt in which the bodies of St. Alexander and one of his fellow-martyrs had been placed. A part of the inscription on its border was preserved, and read as follows: ET ALEXANDRO DEDICATUS VOTUM POSUIT CONSECRANTE URSO EPISCOPO,—"Dedicatus placed this in fulfilment of a vow to —— and Alexander, the Bishop Ursus consecrating it." The Acts supply the missing name of Eventius,—an aged priest, who, it was said, had conversed with some of the apostles themselves. His greater age had at that early and simple time given him the place of honor in the inscription and in men's memory before the youthful, so-called, Pope Alexander. Probably this little church had been built in the fourth century, and here a bishop had been appointed to perform the rites within it.
It was a strange and touching discovery, that of this long-buried, rude country-church,—the very existence of which had been forgotten for more than a thousand years. On the 3d of May, 1855, the day set apart in the calendar to the honor of the saints to whom it was consecrated, the holy services were once more performed upon the ancient altar of the roofless sanctuary. The voices of priest and choir sounded through the long silent chapels, while the larks sang their hymns of gladness over the fields above. On the rough floor, inscriptions, upon which, in the early centuries, the faithful had knelt, were again read by kneeling worshippers. On one broken slab of marble was the word MARTYR; on another, the two words, SPARAGINA FIDELIS; on another, POST VARIAS CURAS, POST LONGE MONITA VITAE.
The catacombs opening from the church have not been entered to a great distance, and though more rudely excavated than most of those nearer the city, as if intended for the burial-places of a poorer population, they are of peculiar interest because many of their graves remain in their original state, and here and there, in the mortar that fastens their tiled fronts, portions of the vessel of glass or pottery that held the collected blood of the martyr laid within are still undisturbed. No pictures of any size or beauty adorn the uneven walls, and no chapels are hollowed out within them. Most of the few inscriptions are scratched upon the mortar,—Spiritus tuus in bono quiescat,—but now and then a bit of marble, once used for a heathen inscription, bears on its other side some Christian words. None of the inscriptions within the church which bear a date are later than the end of the fifth century, and it seems likely that shortly after this time this church of the Campagna was deserted, and its roof falling in, it was soon concealed under a mass of rubbish and of earth, and the grass closed it with its soft and growing protection.
During two years, the uncovered church, with its broken pillars, its cracked altar, its imperfect mosaics, its worn pavement, remained open to the sky, in the midst of solitude. But how could anything with such simple and solemn associations long escape desecration at Rome? How could such an opportunity for restoration be passed over? How could so sacred and venerable a locality be protected from modern superstition and ecclesiastical zeal? In the spring of 1837, preparations were being made for building upon the ground, and a Carthusian convent, it was said, was to be erected, which would enclose within its lifeless walls the remains of the ancient church. Once more, then, it is to be shut out of the sky; and now it is not Nature that asserts her predominance, protecting while she conceals, and throwing her mantle over the martyrs' graves to keep them from sacrilege,—but she is driven away by the builders of the papal court, and all precious old associations are incongruous with those of modern Roman architecture and Roman conventual discipline.
One morning, in the spring of 1855, shortly after the discovery had been made, the Pope went out to visit the Church of St. Alexander. On his return, he stopped to rest in the unoccupied convent adjoining the Church of St. Agnes. Here there was a considerable assemblage of those who had accompanied him, and others who were admitted at this place to join his suite. They were in the second story of the building, and the Pope was in the act of addressing them, when suddenly the old floor, unable to support the unaccustomed weight, gave way, and most of the company fell with it to the floor below. The Pope was thrown down, but did not fall through. The moment was one of great confusion and alarm, the etiquette of the court was disturbed, but no person was killed and no one dangerously hurt. In common language and in Roman belief, it was a miraculous escape. The Pope, attributing his safety to the protection of the Virgin and of St. Agnes, determined at once that the convent should be rebuilt and reoccupied, and the church restored. The work is now complete, and all the ancient charm of time and use, all the venerable look of age and quiet, have been laboriously destroyed, and gaudy, inharmonious color, gilding and polish have been substituted in their place.