Here, also, we find the evidence of the gigantic work of destruction pursued for centuries by the Romans themselves, which we have been in the habit of attributing to the barbarians alone. The barbarians have their share of responsibility in causing the abandonment and the desolation of the Campagna; they may have looted and damaged some edifices, from which there was hope of a booty; they may have profaned churches and oratories erected over the tombs of martyrs; but the wholesale destruction, the obliteration of classical and mediæval monuments, is the work of the Romans and of their successive rulers. To them, more than to the barbarians, we owe the present condition of the Campagna, in the midst of which Rome remains like an oasis in a barren solitude. S. Paul was executed on the Via Laurentina, near some springs called _Aquæ Salviæ_, where a memorial chapel was raised in the fifth century. Its foundations were discovered in 1867, under the present church of S. Paolo alle Tre Fontane (erected in the seventeenth century by Cardinal Aldobrandini) together with historical inscriptions written in Latin and Armenian. I have also to mention another curious discovery. The apocryphal Greek Acts of S. Paul, edited by Tischendorff,[89] assert that the apostle was beheaded near these springs under a stone pine. In 1875, while the Trappists, who are now intrusted with the care of the Abbey of the Tre Fontane, were excavating for the foundations of a water-tank behind the chapel, they found a mass of coins of Nero, together with several pine-cones fossilized by age, and by the pressure of the earth. [Illustration: Tombstone of S. Paul.] The "Liber Pontificalis," i. 178, asserts that Constantine placed the body of S. Paul in a coffin of solid bronze; but no visible trace of it is left. I had the privilege of examining the actual grave December 1, 1891, lowering myself from the _fenestella_ under the altar. I found myself on a flat surface, paved with slabs of marble, on one of which (placed negligently in a slanting direction) are engraved the words: PAVLO APOSTOLO MART··· The inscription belongs to the fourth century. It has been illustrated since by my kind and learned friend, Prof. H. Grisar, to whom I am indebted for much valuable information on subjects which do not come exactly within my line of studies.[90] IV. HOUSES OF CONFESSORS AND MARTYRS. This class of sacred buildings has been splendidly illustrated by the discoveries made by Padre Germano dei Passionisti under the church of SS. Giovanni e Paolo on the Cælian. The good work of Padre Germano is not unknown in America, thanks to Prof. A. L. Frothingham, who has described it in the "American Journal of Archæology." The discoverer himself will shortly publish a voluminous account with the title: _La casa dei SS. Giovanni e Paolo sul monte celio_.