In the cases of Eyraud and Bompard, both man and woman are idle, vicious criminals by instinct. They come together, lead an abandoned life, sinking lower and lower in moral degradation. In the hour of need, crime presents itself as a simple expedient for which neither of them has any natural aversion. The repugnance to evil, if they ever felt it, has long since disappeared from their natures. The man is serious, the woman frivolous, but the criminal tendency in both cases is the same; each performs his or her part in the crime with characteristic aptitude. Mrs. Manning was a creature of much firmer character than her husband, a woman of strong passions, a redoubtable murderess. Without her dominating force Manning might never have committed murder. But he was a criminal before the crime, more than suspected as a railway official of complicity in a considerable train robbery; in his case the suggestion of murder involved only the taking of a step farther in a criminal career. Manning suffered from nerves almost as badly as Macbeth; after the deed he sought to drown the prickings of terror and remorse by heavy drinking Mrs. Manning was never troubled with any feelings of this kind; after the murder of O'Connor the gratification of her sexual passion seemed uppermost in her mind; and she met the consequences of her crime fearlessly. Burke and Hare were a couple of ruffians, tempted by what must have seemed almost fabulous wealth to men of their wretched poverty to commit a series of cruel murders. Hare, with his queer, Mephistophelian countenance, was the wickeder of the two. Burke became haunted as time went on and flew to drink to banish horror, but Hare would seem to have been free from such "compunctious visitings of Nature." He kept his head and turned King's evidence. In the case of the Peltzer brothers we have a man who is of good social position, falling desperately in love with the wife of a successful barrister. The wife, though unhappy in her domestic life, refuses to become her lover's mistress; marriage is the only way to secure her. So Armand Peltzer plots to murder the husband. For this purpose he calls in the help of a brother, a ne'er-do-well, who has left his native country under a cloud. He sends for this dubious person to Europe, and there between them they plan the murder of the inconvenient husband. Though the idea of the crime comes from the one brother, the other receives the idea without repugnance and enters wholeheartedly into the commission of the murder. The ascendency of the one is evident, but he knows his man, is sure that he will have no difficulty in securing the other's co-operation in his felonious purpose. Armand Peltzer should have lived in the Italy of the Renaissance.