2. The remains, more or less perfect, of a staircase or staircases leading down to the sacred crypt containing a tomb of some great confessor known and honoured in the tradition of the Church.
3. The presence of a “luminare” or shaft, sometimes of considerable size, which was constructed to give light and air to a subterranean chamber in the Catacombs, indicated that in the immediate neighbourhood of the “luminare” an historic crypt had once existed. These openings or shafts were mostly the work of Pope Damasus and his successors in the latter years of the fourth and in the earlier years of the fifth centuries.
4. Below—in some of the ruined corridors of tombs and in certain of the cubicula or separate chambers leading out of the corridors—on the walls a number of “graffiti” or inscriptions, often very rudely graved or painted, are visible, some of the inscriptions or questions being simply a name, others containing a brief prayer for the writer or for one dear to the writer. It was evident that the presence of such inscriptions indicated the immediate neighbourhood of an historic crypt which once contained the remains of a revered “great one,”—not unfrequently the name of the “great one” was included in some of the graffiti.
Such “graffiti” were clearly the work of the many pilgrims to the Catacombs in the fifth and following centuries.
5. In certain of the cubicula or separate chambers leading out of the corridors, remains of paintings, evidently of a period much later than the original Catacomb work, are discernible—paintings which belong to the Byzantine rather than to any classical school of art, and which cannot be dated earlier than the sixth or seventh centuries. The existence of such later decorative work clearly indicated that the spot so adorned was one of traditional sanctity, and no doubt had been the resting-place of a venerated saint and martyr.
6. In his “materials” for the identification of the historic crypts De Rossi found the inscriptions of Pope Damasus, who died A.D. 384, of the greatest assistance.
Damasus’ love for and work in the Catacombs is well known. He was a considerable poet, and precious fragments of poetical inscriptions composed by him have been found in many of the more important Catacombs which have been explored. These inscriptions were engraved on marble tablets by his friend and skilful artist Furius Dionysius Filocalus in clear beautiful characters. These fragments have been in many cases put together, and where the broken pieces were wanting have been wonderfully restored with the aid of “syllogæ” or collections of early Christian inscriptions gathered mostly in the ninth century by the industry of the monks. These “syllogæ” or collections have preserved for us some forty of the inscriptions of Pope Damasus in honour of martyrs and confessors buried in the Catacombs. With perhaps one solitary exception, they are all written in hexameter verse.
Such collections of early Christian inscriptions have been preserved in the libraries of such monasteries as Einsiedeln, S. Riquier, S. Gall, etc.
The result of the forty years of De Rossi’s researches and work in the Catacombs, based on the above-mentioned historical documents and on the evidence derived from what he found in the ruined corridors of tombs and the chambers leading out of them, has been that, whereas before his time at most three important historical crypts were known, now already more than fifteen[122] of these have been clearly identified, a wonderful and striking proof of the reality of the sufferings and constancy of the heroes and heroines of the faith in the first two hundred and fifty years of the existence of the religion of Jesus—sufferings and constancy which resulted in the final triumph of Christianity.