The sense of hearing in somnambulism is not often suspended, for, generally speaking, somnambulists will answer questions and carry on conversation; but it is remarkable that the same ear which may be deaf to the loudest noises, will perceive even a whisper from one particular person with whom the sleeper may alone appear to hold communion. In the "Transactions of the Medical Society" at Breslau, we meet with the case of a somnambulist who did not hear even the report of a pistol fired close to him. In another instance, that of Signor Augustin, an Italian nobleman, his servants could not arouse him from his sleep by any description of noise--even blowing a trumpet in his ear. On the other hand, the same individual would, in another paroxysm, apply his ear to the key-hole of the door, and listen attentively to noises which he heard in the kitchen. The sense of smell, as we have observed, is frequently altered. Brimstone and phosphorus are said to have a pleasant scent to the somnambulist, but sometimes it appears completely abolished. In one case, a snuff-box filled with coffee, was given to a somnambulist, who took it as he would have taken snuff, without perceiving the difference. So also is it with taste. Some somnambulists have not been able to distinguish wine from water. Another very remarkable circumstance has been observed in somnambulism; it is, that persons in this state have exhibited an extraordinary exaltation of knowledge. Two females mentioned by Bertrand, expressed themselves, during the paroxysms, very distinctly in Latin; although they afterward admitted having an imperfect acquaintance with this language. An ignorant servant girl, described by Dr. Dewar, evinced an astonishing knowledge of astronomy and geography, and expressed herself in her own language in a manner which, though often ludicrous, showed an understanding of the subject. It was afterward discovered that her notions on these subjects had been derived from hearing a tutor giving instructions to the young people of the family. A woman in the Infirmary of Edinburgh, on account of an affection of this kind, during her somnambulism, mimicked the manner of the physicians, and repeated correctly some of their prescriptions in the Latin language. Many of these apparent wonders are referable to the circumstance of old associations being vividly recalled to the mind; this very frequently happens also in the delirium of fever. There is nothing miraculous in such cases, although upon them are founded a host of stories descriptive of persons in their sleep speaking unknown languages, predicting future events, and being suddenly possessed of inspiration.