when the Emperor and the Pope came, they left him in his dungeon. Now at Gaeta there lived a very holy man, who was Saint Nilus, and who afterwards founded the monastery of Grottaferrata, where there are beautiful wall paintings to this day. He was a Greek, like John of Calabria, and though he detested the antipope he had pity on the man and felt compassion for his countryman. So he journeyed to Rome and came before Otto and Gregory, who received him with perfect devotion, as a saint, and he asked of them that they should give him the wretched John, 'who,' he said, 'held both of you in his arms at the Font of Baptism,' though he was grievously fallen since that day by his great hypocrisy. Then the Emperor was filled with pity, and answered that the saint might have the antipope alive, if he himself would then remain in Rome and direct the monastery of Saint Anastasia of the Greeks. The holy man was willing to sacrifice his life of solitary meditation for the sake of his wretched countryman, and he would have obtained the fulfilment of his request from Otto; but Pope Gregory remembered how he himself had been driven out penniless and scantily clothed, to make way for John of Calabria, and his heart was hardened, and he would not let the prisoner go. Wherefore Saint Nilus foretold that because neither the Pope nor the Emperor would have mercy, the wrath of God should overtake them both. And indeed they were both cut off in the flower of their youth--Gregory within one year, and Otto not long afterwards. Meanwhile they sent Nilus away and laid siege to the Castle of Sant' Angelo, where Crescenzio and his men had shut themselves up with a good store of food and arms. No one had ever taken that fortress, nor did any one believe that it could be stormed. But Pope and Emperor were young and brave and angry, and they had a great army, and the people of Rome were with them, every man. They used such engines as they had,--catapults, and battering-rams, and ladders; and yet Crescenzio laughed, for the stone walls were harder than the stone missiles, and higher than the tallest ladders, and so thick that fire could not heat them from without, nor battering-ram loosen a single block in a single course; and many assaults were repelled, and many a brave soldier fell writhing and broken into the deep ditch with his ladder upon him.