Both the danger and the possible usefulness of hypnotism may be illustrated by an actual case. It is that of a man all of whose companions were destroyed by the bursting of a shell, and who suffered for months afterwards from complete loss of memory. A medical man hypnotised him, and perhaps with undue tactlessness, brought back the memory of the critical incident at the front, stripped of all the episodes which led up to or followed it. This excited in him the most violent emotions, and he became sick with terror; for the revived incident seemed perfectly real to him, or, as he described it afterwards, “it jumped up against him,” and for weeks he was so utterly terrified that he would not go near the doctor. Even though he could not retain the memory of any other recent events the horror of that experience seemed to have made him remember his dread of a particular medical man. But by making use of the information gained during that revival under hypnosis of an incident unknown to anyone but the patient, which his amnesia up till then had kept sealed up, it became possible for another medical officer to bridge the gap between his memory of previous events and the experiences which the patient was known to have had in the military hospitals. In speaking of the results of hypnotic treatment as being brilliant but erratic, it is important to remember that the same observations apply to suggestion without hypnosis. For instance, the application of electricity to the vocal cords in cases of hysterical aphonia affords an admirable illustration of the treatment by suggestion, even if the method savours of charlatanism. An excellent demonstration of the part which psychical factors play in such cases is afforded by the story of a sailor on the German battle-cruiser _Derfflinger_, recorded by Blässig.[34] “A seaman from the _Derfflinger_ was brought into a naval hospital with loss of voice on Dec. 22nd, 1914, and could speak only in a whisper. He said that he had always had good health, with the exception that as a child he had diphtheria, but recovered without tracheotomy or any complication. His voice had always been clear and well under control. At the beginning of December he had a slight cold, which he attributed to sentry duty on deck in very stormy and wet weather. While in the ammunition chamber of the big guns he was greatly upset during the firing and suddenly lost his voice. After fourteen days he recovered his speech. On Feb. 12th, 1915, he returned to hospital with complete loss of voice, immediately after the naval engagement in the North Sea. On Feb. 15th he was treated with electricity, directly applied to the vocal cords, and on March 20th he was discharged with complete recovery of his speech. But on returning to duty, as soon as he went on board his ship his voice was suddenly lost for the third time, and he remained aphonic.”