This is a kind of dream which has occurred in all ages, and has at times been put down to divine interposition. Sixteen centuries ago Bishop Synesius of Ptolemais wrote that in his hunting days a dream revealed to him an idea for a trap which he successfully employed in snaring animals, and at the present time inventions made in dreams have been successfully patented. The Rev. Nehemiah Curnock, who lately succeeded in deciphering Wesley's _Journal_, has stated that an important missing clue to the cypher came to him in a dream. A friend of my own, an expert in chemistry, was not long since in frequent communication with a practical manufacturer, assisting him in his inventions by scientific advice. One day the manufacturer wrote to my friend asking if the latter had been thinking of him during the night, for he had been much puzzled by a difficulty, and during the night had seen a vision of my friend who explained the solution of the difficulty; in the morning the proposed solution proved successful. There was, however, no telepathic element in the case; the dreamer's solution was his own. An interesting group of cases in this class is furnished by the dreams in which the dreamer, in opposition to his waking judgment, sees an acquaintance in whom he reposes trust acting in a manner unworthy of that trust, subsequent events proving that the estimate formed during sleep was sounder than that of waking life. Hawthorne (in his _American Notebooks_), Greenwood, Jewell, and others have recorded cases of this kind. Various as these phenomena are, they fall into the same scheme. They all help to illustrate the fact that though on one side mental life in sleep is feeble and defective, on the other side it shows a tendency to vigorous excess. Sleep, as we know, involves a relaxation of tension, both physical and psychic; attention is no longer focused at a deliberately selected spot.[207] The voluntary field becomes narrower, but the involuntary field becomes extended. Thus it happens that the contents of our minds fall into a new order, an order which is often fantastic but, on the other hand, is sometimes a more natural and even a more rational order than that we attain in waking life. Our eyes close, our muscles grow slack, the reins fall from our hands. But it sometimes happens that the horse knows the road home even better than we know it ourselves. Hypermnesia, or abnormally wide range of recollection, is not the only or the most common modification of memory during sleep. We find much more commonly, and indeed as one of the chief characteristics of sleep, an abnormally narrow range of recollection. We find, also, and perhaps as a result of that narrow range, paramnesia or perversion of memory. The best known form of paramnesia is that in which we have the illusion that the event which is at the moment happening to us has happened to us before.[208]