Claudius distinguished his reign by the execution of many important works. At the mouth of the Tiber he constructed a magnificent harbor, called the Portus Romanus. The Claudian Aqueduct, which he completed, was a stupendous work, bringing water to the city from a distance of forty-five miles. The delight of the people in gladiatorial shows had at this time become almost an insane frenzy. Claudius determined to give an entertainment that should render insignificant all similar efforts. Upon a large lake, whose sloping bank afforded seats for the vast multitudes of spectators, he exhibited a naval battle, in which two opposing fleets, bearing nineteen thousand gladiators, fought as though in real battle, till the water was filled with thousands of bodies, and covered with the fragments of the broken ships. Throughout his life Claudius was ruled by intriguing favorites and unworthy wives. For his fourth wife Claudius married the "wicked Agrippina," who secured his death by means of a dish of poisoned mushrooms, in order to make place for the succession of her son Nero. REIGN OF NERO (A.D. 54-68).--Nero was fortunate in having for his preceptor the great philosopher and moralist Seneca; but never was teacher more unfortunate in his pupil. For five years Nero ruled with moderation and equity. He then broke away from the guidance of his tutor Seneca, and entered upon a career filled with crimes of almost incredible enormity. The dagger and poison--the latter a means of murder the use of which at Rome had become a "fine art," and was in the hands of those who made it a regular profession--were employed almost unceasingly, to remove persons that had incurred his hatred, or who possessed wealth that he coveted. It was in the tenth year of his reign that the so-called Great Fire laid more than half of Rome in ashes. It was rumored that Nero had ordered the conflagration to be lighted, and that from the roof of his palace he had enjoyed the spectacle, and amused himself by singing a poem which he had written, entitled the "Sack of Troy." Nero did everything in his power to discredit the rumor. To turn attention from himself, he accused the Christians of having conspired to destroy the city, in order to help out their prophecies. The doctrine which was taught by some of the new sect respecting the second coming of Christ, and the destruction of the world by fire, lent color to the charge. The persecution that followed was one of the most cruel recorded in the history of the Church. Many victims were covered with pitch and burned at night, to serve as torches in the imperial gardens. Tradition preserves the names of the Apostles Peter and Paul as victims of this Neronian persecution.