The author of this amusing narrative, Henry Cockton, is better known as the author of "Valentine Vox, the Ventriloquist, Stanley Thome, " and "George St. George Julian, the Prince." He is a lively sketcher, particularly good at the delineation of infirmities. This is a mirth-provoking volume. There is considerable ingenuity in the management of the 'Somnambulist' by which, while he bedevils the whole neighborhood, not only is he unsuspected by his victims, but even by himself. The character of Tom Deloime is particularly good, and his abuse of language delightful. Read as a book of mere fun, 'Sylvester Sound' will hardly disappoint the hypochondriac.- "Southern and Western Monthly Magazine and Review" * * * * * An excerpt from the beginning of the Author's PREFACE: Somnambulism has been in all ages known. Aristotle says, "There are individuals who rise in their sleep and walk about, seeing as clearly as those that are awake." Diogenes Laertius states that Theon, the philosopher, was a somnambulist. Galen slept whilst on a road, and pursued his journey, until he was awakened by tripping on a stone. Felix Pater fell asleep while playing on the lute, and was startled only by the fall of the instrument; while the present age teems with instances of the most astounding character. Dr. Dyce, of Aberdeen, describes the case of "a girl, in which this affection began with fits of somnolency, which came upon her suddenly during the day, and from which she could at first be roused by shaking or by being taken into the open air. During these attacks she was in the habit of talking of things that seemed to pass before her like a dream, and was not at the time sensible of anything that was said to her. On one occasion she repeated the entire of the baptismal service of the Church of England, and concluded with an extemporary prayer. In her subsequent paroxysms she began to understand what was said to her, and to answer with a considerable degree of consistency, though these replies were in a certain measure influenced by her hallucination. She also became capable of following her usual employment during the paroxysm. At one time she would lay out the table for breakfast, and repeatedly dressed herself and the children, her eyes remaining shut the whole time. The remarkable circumstance was now discovered that, during the paroxysm, she had a distinct recollection of what had taken place in former attacks, though she had not the slightest recollection of it during the intervals. She was taken to church during the paroxysm, and attended the service with apparent devotion, and at one time was so affected by the sermon that she actually shed tears; yet in the interval she had no recollection whatever of the circumstance, but in the following paroxysm she gave a most distinct account of it, and actually repeated the passage of the sermon that had so much affected her. This sort of somnambulism, relating distinctly to two periods, has been called, perhaps erroneously, a state of double consciousness." "A girl aged seven years," says Dr. Abercrombie, "an orphan of the lowest rank, residing in the house of a farmer, by whom she was employed in tending cattle, was accustomed to sleep in an apartment separated by a very thin partition from one which was frequently occupied by an itinerant fiddler. This person was a musician of very considerable skill, and often spent a part of the night in performing pieces of a refined description; but his performance was not taken notice of by the child, except as a disagreeable noise. After a residence of six months in this family she fell into bad health, and was removed to the house of a benevolent lady, where, on her recovery after a protracted illness, she was employed as a servant....