Thus with Plutarch, as with his master Plato, a future world is the grand court of appeal from the anomalies and inequalities of this world; and, following the example of the Gorgias and the Republic, he reserves to the last a terrible picture of the torments held in store for those who have not expiated their transgressions on earth, describing them as they are supposed to have been witnessed by a human soul temporarily separated from the body for the purpose of viewing and reporting on this final manifestation of divine justice. It would appear, however, from the narrative in question that future punishments are not eternal. After a more or less protracted period of expiation, the immortal soul is restored to the upper world, under whatever embodiment seems most appropriate to its former career. Among those whose turn has arrived for entering on a new existence at the moment when Plutarchs visitor makes his descent to hell, is the soul of Nero. The wicked Emperor has just been condemned to assume the form of a viper, when a great light shines forth, and from the midst of the light a voice is heard crying:268 Let him reappear under the guise of a song-bird haunting the neighbourhood of marshes and meres; for he has already paid the penalty of his guilt, and the gods owe him some kindness for having liberated Greece, the best and most beloved by them of all the nations that he ruled.Leaving out the matter of a positive relative movement between shafts, which belts as a means of transmitting power cannot insure, there are the following conditions that must be considered in determining whether belts or other means should be employed in transmitting power from one machine to another or between the parts of machines.About midnight I was roused by an infernal noise in the street. People yelled and screamed most fearfully, and I heard rifle-shots also.The difference between hand and machine operations, and the labour-saving effect of machines, will be farther spoken of in another place; the subject is alluded to here, only to enable the reader to more fully distinguish between machinery of transmission and machinery of application. Machinery of application, directed to what has been termed compression processes, such as steam hammers, drops, presses, rolling mills, and so on, act upon material that is naturally soft and ductile, or when it is softened by heat, as in the case of forging.