Another question concerning the behavior of early Christians has reference to their military service under the imperial eagles, and to the cases of conscience which may have arisen from it. On this I may refer the reader to the works of Mamachi, Lami, Baumgarten, Le Blant, and de Rossi,[13] who have discussed the subject thoroughly. Speaking from the point of view of material evidence, I have to record several discoveries which prove that officers and men of the _cohortes prætoriæ_ and _urbanæ_ could serve with equal loyalty their God and their sovereign. In November, 1885, I was present at the discovery of a marble sarcophagus in the military burial-grounds of the Via Salaria, opposite the gate of the Villa Albani. It bore two inscriptions, one on the lid, the other on the body. The first defies interpretation;[14] the second mentions the name of a little girl, Publia Ælia Proba, who was the daughter of a captain of the ninth battalion of the prætorians, and a lady named Clodia Plautia. They were all Christians; but for a reason unknown to us, they avoided making a show of their persuasion, and were buried among the gentiles. Another stray Christian military tomb, erected by a captain of the sixth battalion, named Claudius Ingenuus, was found, in 1868, in the Vigna Grandi, near S. Sebastiano. Here also we find the intention of avoiding an open profession of faith. A regular cemetery of Christian prætorians was found in the spring of the same year by Marchese Francesco Patrizi, in his villa adjoining the prætorian camp. It is neither large nor interesting, and it seems to prove that the gospel must have made but few proselytes in the imperial barracks. * * * * * We must not believe that the transformation of Rome from a pagan into a Christian city was a sudden and unexpected event, which took the world by surprise. It was the natural result of the work of three centuries, brought to maturity under Constantine by an inevitable reaction against the violence of Diocletian's rule. It was not a revolution or a conversion in the true sense of these words; it was the official recognition of a state of things which had long ceased to be a secret. The moral superiority of the new doctrines over the old religions was so evident, so overpowering, that the result of the struggle had been a foregone conclusion since the age of the first apologists. The revolution was an exceedingly mild one, the transformation almost imperceptible. No violence was resorted to, and the tolerance and mutual benevolence so characteristic of the Italian race was adopted as the fundamental policy of State and Church.