EV. You have adopted the common error of metaphysicians. If, in the abstraction of waking moments, some persons talk to themselves, as it were unconsciously, so, from the _reflex_ influence, may volition and motion occur, with as little self-feeling. That the _immediate_ impression, however, and a necessity of action, may combine, is illustrated by Dr. Beattie’s case of the officer who could be thus excited in his sleep. By a whisper in his ear, he was induced to go through the whole ceremony of a duel, and did not completely wake until the report of his pistol roused him. This gentleman was also told that he had fallen overboard, and he began to imitate the motions of swimming; then that a shark was following him, when he would dive off his couch upon the floor; and when he was told that the battle was raging around him, he proved himself an arrant coward by running away. Somnambulism may be induced by congestion or irritation of _that point_ where the _incident_ nerve blends with the _grey matter_ of the spinal marrow, producing internal irritation, as the tickling of the foot does through the _cutaneous_ nerves of a senseless limb. CAST. We are thankless creatures, dear Evelyn, but all this reiteration bewilders me, does it not you, Ida? Yet, in my simplicity, I can but think it unphilosophical entirely to disregard the _will_ as the spring of our actions. EV. If I must EXPLAIN, fair lady, I cannot avoid prolixity. But to your question I will answer, no; for somnambulism _may be excited_ by the _memory of an intention_. In the experiment made by the committee of the physical society of Lausanne, on the Sieur Devaud, of Vevay, it was proved that on the evening before the fit of somnambulism, his head was heavy, and he had a sense of oppression on his eye-lids. If, at this time, the mind was impressed by some legend, or story, or incident, the actions of the sleep-walk were perfectly _coincident with such a subject_. If a romantic tale of banditti were related, his alarm would be apparent in his subsequent sleep. In this somnambulist was beautifully illustrated the effect of permanent impression on the brain, rendering, for a time, the sense of vision useless; for having once perused his paper, it was so imprinted on his mind, that the _exact_ spot for each letter was _exactly_ fixed on _by the finger_. And we have heard of one more interesting case, in which the somnambule, remembering that he had made errors in his writing, traced, on a blank paper substituted for that written on, the corrections, _in the very places corresponding to the erroneous writing_. And that here was memory was proved in this, that during the time his eyes were shut, the pen was dropped on the _very spot_ where the inkstand stood; but this being removed, no ink was obtained, and the writing was blank.