must have arisen in the night and traveled all over the ship."
As already remarked, talking in the sleep is the simplest form in which somnambulism appears. Usually dreamers do not move their limbs, and especially are incapable of rising or walking, because under ordinary circumstances the impulse to do these things is created by the will, and it requires a strong exertion thereof to overcome the inertia of the body and to begin the complex series of motions necessary to move from place to place. In sleep the image is not sufficiently vivid to take control of the muscles.
Cicero says that if it had been so ordered by nature that we should actually do in sleep all that we dream of doing, every man would have to be bound to the bed before going to sleep. The justice of this remark is illustrated in the case of somnambulism.
The peculiarity of somnambulism which identifies it with dreaming is complete absorption of all the powers and faculties in the image. A voice falling in with that may be heard; one speaking of other matters is unnoticed. Dreamers who have never been somnambulists could, by a process of training, be transformed into such; and, what is more important, the tendency can be destroyed if taken in time.
Sir Henry Holland says that it is an old trick to put the hand into cold water, or to produce some other sensation not so active as to awaken, but sufficient to draw the mind from a more profound to a lighter slumber; thus the sleeper may be made to answer questions.
Great light has been reflected upon natural by artificial somnambulism, known by the various names of mesmerism, animal magnetism, electro-biology, hypnotism, etc. It is an astonishing fact that in these states a particular sense may be exalted so as to give
