The Mamertine prison is composed of two square subterranean chambers, one below the other, with only one round aperture in the centre of each vault, through which alone light, air, food, furniture, and men could pass. When the upper story was full, we may imagine how much of the two first could reach the lower. No other means of ventilation, drainage, or access could exist. The walls, of large stone blocks, had, or rather have, rings fastened into them for securing the prisoners; but many used to be laid on the floor, with their feet fastened in the stocks; and the ingenious cruelty of the persecutors often increased the discomfort of the damp stone floor, by strewing with broken potsherds this only bed allowed to the mangled limbs, and welted backs, of the tortured Christians. Hence we have in Africa a company of martyrs, headed by SS. Saturninus and Dativus, who all perished through their sufferings in prison. And the acts of the Lyonese martyrs inform us that many new-comers expired in the jail, killed by severities, before their bodies had endured any torments; while, on the contrary, some who returned to it so cruelly tortured that their recovery appeared hopeless, without any medical or other assistance, there regained their health.[164] At the same time the Christians bought access to these abodes of pain, but not of sorrow, and furnished whatever could, under such circumstances, relieve the sufferings and increase the comforts, temporal and spiritual, of these most cherished and venerated of their brethren. Roman justice required at least the outward forms of trial, and hence the Christian captives were led from their dungeons before the tribunal; where they were subjected to an interrogatory, of which most precious examples have been preserved in the proconsular Acts of Martyrs, just as they were entered by the secretary or registrar of the court. When the Bishop of Lyons, Pothinus, now in his ninetieth year, was asked, “Who is the God of the Christians?” he replied, with simple dignity, “If thou shalt be worthy, thou shalt know.”[165] Sometimes the judge would enter into a discussion with his prisoner, and necessarily get the worst of it; though the latter would seldom go further with him than simply reiterating his plain profession of the Christian faith. Often, as in the case of one Ptolomæus, beautifully recited by St. Justin, and in that of St. Perpetua, he was content to ask the simple question, Art thou a Christian? and upon an affirmative reply, proceeded to pronounce capital sentence. Pancratius and his companion stood before the judge; for it wanted only three days to the _munus_, or games, at which they were to “fight with wild beasts.” “What art thou?” he asked of one. “I am a Christian, by the help of God,” was the rejoinder. “And who art thou?” said the prefect to Rusticus.