On the last day of May in that year, some labourers who were digging _pozzolana_ in a vineyard on the Via Salara happened to break into a gallery of graves ornamented with Christian paintings, Greek and Latin inscriptions, and two or three sculptured sarcophagi. Such a discovery in an age of great intellectual activity naturally excited much curiosity, so that persons of all classes flocked to see it. “Rome was amazed,” writes a cotemporary author, “at finding that she had other cities unknown to her concealed beneath her own suburbs, beginning now to understand what she had before only heard or read of;” “and in that day,” says De Rossi, “was born the name and the knowledge of _Roma Sotterranea_.” Would that there had been born also at the same time, in the highest quarters of the Church, a sufficient appreciation of the importance of the discovery to have caused them to take it under their own immediate superintendence, and to pursue with care and diligence the researches to which it invited them. Had the ecclesiastical authorities of Rome adopted from the first some such means for the guardianship of the Catacombs and their contents as Pope Pius IX. in 1851, by intrusting them to a Commission of Sacred Archæology, or even as Clement IX. in 1688, by forbidding all excavations and removal of relics from them by private individuals, they would have been to us almost a Christian Pompeii—a true “city of the dead,” yet exhibiting such abundant and authentic records of the first ages of the Roman Church as would have enabled us to form a very lifelike picture of our forefathers in the faith. But alas! the work of destruction began almost as soon as it was discovered that there was anything to destroy; and the labours of the few who appreciated what had been found, and would fain have handed down to posterity an accurate account of it, could hardly keep pace with the destroyer. From the first there were a chosen few who laboured hard in this new field of Christian archæology—in particular, a Spanish Dominican friar and two young Flemish laymen; but the fruits of their labours were never given to the public; and when Bosio took the work in hand, only fifteen years after the date of the original discovery, the paintings in the crypts on the Via Salara had already been destroyed.