_Somnambulic Life._--We come now to the last term of the series, the simplest, yet perhaps the rarest form of the affection. In this form, the patient seems perfectly awake; he is in possession of all his senses; he is capable of sustained and rational volition; he lives and behaves, in short, like any other person. But his life is divided into periods which are, so far as consciousness is concerned, completely distinct from each other. This double-consciousness may be exhibited but once in a lifetime, or it may be frequently repeated, so that the patient oscillates between the two states until it becomes doubtful which is the natural condition and which is the acquired. These states of double-consciousness are divided from each other by a more or less complete break in the chain of memory. The residual strata which, so to speak, have been deposited from the sea of events upon the floor of memory, have become broken and “faulted.” The line of rupture marks the division between the two fields of consciousness; they no longer lie in the same plane, consequently there can be little or no continuity of memory between them. The events which transpire in one state affect the mind so long as, and whenever it is in connection with the cerebral register which is fitted to that state; as soon as the connection is shifted, the mind takes cognizance of the events that are recorded upon the other portion of the register, but, for want of physical continuity between the different portions of the record, the mind cannot at once receive a continuously connected report from the entire organ of recollection. From this results a mode of life essentially similar to the life of certain epileptics who are ushered by each seizure into a state of apparently conscious activity of which they have no recollection after recovery. Thus, one of my epileptic patients, who was subject to seizures, both of the convulsive and the non-convulsive form of the disease, on one occasion left home, after a fit, and traveled a considerable distance into the country, putting up for the night at taverns and farm houses, and apparently behaving like any other respectable citizen. It was three weeks before he came to himself. On recovering his normal consciousness, the period of his wanderings was a perfect blank in his memory. Such attacks are usually of shorter duration, and are more frequently associated with hysteria; bearing to the hysterical paroxysm the same relation which they share with the epileptic fit. When the predisposing temperament exists, a great variety of excitations may serve to produce the phenomena, so that unless careful observation is employed, the truly somnambulic character of the paroxysm may easily be overlooked. Thus, the true nature of the affection was not suspected by the early attendants of the patient who became the subject of lethargic stupor, as related on page 173. Under the influence of powerful