Sleep walking or night wandering, known also by its Latin name ofnoctambulism, is a well-known phenomenon. Somnambulism is not so good a term for it, since that signifies too many things. In sleep walking a person rises from his bed in the night, apparently asleep, walks around with closed or half opened eyes, but without perceiving anything, yet performs all sorts of apparently purposeful and often quite complicated actions and gives correct answers to questions, without afterward the least knowledge of what he has said or done. If this all happens at the very time and under the influence of the full moon, it is spoken of as moon walking or being moonstruck.The author's application of psychoanalysis to these problems has the directness and explicitness which we are accustomed to find in Freud's own writings. This is as true in the literary portion of the work as in the medical but it never intrudes to mar the intrinsic beauty of certain of the selections nor the force of the intuitive revelations which the writers of the preceding science have made in regard to sleep walking and walking in the moonlight.