There is a very curious case on record, of a lady whose “memory was capacious, and well stored with a copious stock of ideas. Unexpectedly, and without any forewarning, she fell into a profound sleep, which continued several hours beyond the ordinary term. On waking, she was discovered to have lost every trait of acquired knowledge; her memory was a blank. All vestiges, both of words and things, were obliterated and gone; it was found necessary for her to learn every thing again. She even acquired by new efforts the art of spelling, reading, writing, and calculating, and gradually became acquainted with the persons and objects around, like a being for the first time brought into the world. In these exercises she made considerable proficiency; but, after a few months, another fit of somnolency invaded her. On rousing from it, she found herself restored to the state she was in _before the first paroxysm_; but she was wholly ignorant of every event and occurrence that had befallen her afterwards. The former condition of her existence she now calls the _old_ state, and the latter the _new_ state; and she is as unconscious of her double character as two distinct persons are of their respective natures. For example, in her old state, she possesses all her original knowledge; in her new state, only what she acquired since. If a lady or gentleman be introduced to her in the old state, and _vice versâ_ (so indeed of all other matters), to _know them_ satisfactorily she must learn them in both states. In the old state she possesses fine powers of penmanship, while in the new she writes a poor awkward hand, not having had time or means to become expert! During four years and upwards, she has had periodical transitions from one of these states to the other. The alterations are always consequent upon a long and sound sleep. Both the lady and her family are now capable of conducting the affair without embarrassment; by simply knowing whether she is in the old or new state, they regulate the intercourse, and govern themselves accordingly!” Other instances are more protracted; the impressions _previous to a certain moment_ only being capable of renewal. Mrs. S——, an intelligent lady, belonging to a respectable family in the state of New York, some years ago undertook a piece of fine needle-work. She devoted her time to it almost constantly for a number of days; but before she had completed it she became suddenly delirious. In this state, without experiencing any material abatement of her disease, she continued for about seven years, when her reason was suddenly restored. One of the first questions which she asked on this convalescence _related to her needle-work_. It is a remarkable fact that, during the long continuance of her delirium, she said nothing, so far as was recollected, about her needle-work, nor concerning any such subjects as usually occupied her attention when in health.