the Via Tiburtina which stretches across the now desolate Campagna to Tivoli, on the northern side of the road almost opposite the Cemetery of S. Cyriaca on which stands the Basilica of S. Laurentius just described, is the Catacomb of S. Hippolytus. It is only comparatively recently that this cemetery has been really explored, and much still remains to be excavated here. A small basilica underground was discovered, with the historic crypt in which the once famous martyr was buried. The corridors around have been sadly ravaged again and again by barbarian invaders in the fifth and following centuries, and the whole catacomb is in ruin, and has been only in part investigated. It is evidently of considerable extent. Proximity to the tomb of the great scholar martyr was evidently a privilege eagerly sought by many from the middle years of the third century onward. The numbers of Pilgrim "Graffiti" or inscriptions more or less roughly carved and painted in the neighbourhood of the sanctuary, tell us that the spot where the remains of Hippolytus lay, was long the object of reverent pilgrimage after the Peace of the Church all through the fourth and following centuries. The Itineraries mention many martyrs buried here, among whom S. Genesius is perhaps the best known; he was a celebrated actor; once a mocker at the religion of which eventually he became the brave confessor; he died for his faith.
But the glory of this now ruined cemetery was the tomb of S. Hippolytus. He has been well described by Bishop Lightfoot in his long and exhaustive Memoir (Apostolic Fathers, Part 1. vol. ii.).
"The position and influence of Hippolytus were unique among the Roman Christians of his age. He linked together the learning and the traditions of the East, the original home of Christianity, with the practical energy of the West, the scene of his own life labours. He was by far the most learned man in the Western Church. . . . Though he lived till within a few years of the middle of the third century, he could trace his pedigree back by only three steps, literary as well as ministerial, to the life and teaching of the Saviour Himself, Irenæus, of whom he was the pupil, Polycarp, and S. John. This
