CALIGULA.--There was no law for the regulation of the succession. But the Senate, the prætorians, and the people united in calling to the throne _Caius_, the son of Germanicus (37-41). This ruler, called _Caligula_, at first mild and generous in his doings, soon rushed into such excesses of savage cruelty and monstrous vice that he was thought to be half-deranged. He was fond of seeing with his own eyes the infliction of tortures. His wild extravagance in the matter of public games and in building drained the resources of the empire. After four years, this madman was cut down by two of his guards whom he had grievously insulted. CLAUDIUS.--_Claudius_, the uncle and successor of _Caligula_, and the son of Drusus and Antonia, was not bad, but weak. He was a student and a recluse in his habits. His favorites and nearest connections were unprincipled. The depravity of his wife, _Messalina_, was such that he did right in sanctioning her death. The immoral and ambitious _Agrippina_, whom he next married, had an influence less malign. But she was unfaithful to her husband; and this fact, together with the fear she felt that _Nero_, her son by her first marriage, would be excluded from the throne, impelled her to the crime of taking the life of _Claudius_ by poison. NERO.--_Nero_ reigned from 54 to 68. He was the grandson of Germanicus, and had been the pupil of the philosopher _Seneca_, and of _Burrus_, an excellent man, the captain of the Prætorian Guard. The first five years of Nero's reign were honorably distinguished from the portion of it that followed. When a warrant for the execution of a criminal was brought to him, he regretted that he had ever learned to write. His first great crime was the poisoning of _Britannicus_, the son of _Claudius_. Nero became enamored of a fierce and ambitious woman, _Poppæa Sabina_. On the basis of false charges, he took the life of his wife, _Octavia_, the daughter of Claudius (A.D. 62). His criminal mother, Agrippina, after various previous attempts made by him to destroy her, was dispatched by his command (A.D. 59). His unbridled cruelty and jealousy moved him to order _Seneca_, one of the men to whom he owed most, to commit suicide. He came forward as a musician, and nothing delighted him so much as the applause rendered to his musical performances. He recited his own poems, and was stung with jealousy when he found himself outdone by _Lucan_. His eagerness to figure as a charioteer prompted him, early in his reign, to construct a circus in his own grounds on the _Vatican_, where he could exhibit his skill as a coachman to a throng of delighted spectators. At length he appeared, lyre in hand, on the stage before the populace. Senators of high descent, and matrons of noble family, were induced by his example and commands to come forward in public as dancers and play-actors. The public treasure he squandered in expensive shows, and in the lavish distribution of presents in connection with them.