One of the most striking and important peculiarities of the subjective mind, as distinguished from the objective, consists in its prodigious memory. It would perhaps be hazardous to say that the memory of the subjective mind is perfect, but there is good ground for believing that such a proposition would be substantially true. It must be understood that this remark applies only to the most profoundly subjective state and to the most favorable conditions. In all degrees of hypnotic sleep, however, the exaltation of the memory is one of the most pronounced of the attendant phenomena. This has been observed by all hypnotists, especially by those who make their experiments with a view of studying the mental action of the subject. Psychologists of all shades of belief have recognized the phenomena, and many have declared their conviction that the minutest details of acquired knowledge are recorded upon the tablets of the mind, and that they only require favorable conditions to reveal their treasures. Sir William Hamilton, in his "Lectures on Metaphysics," page 236, designates the phenomenon as "latent memory." He says:-- "The evidence on this point shows that the mind frequently contains whole systems of knowledge, which, though in our normal state they have faded into absolute oblivion, may, in certain abnormal states--as madness, febrile delirium, somnambulism, catalepsy, etc.--flash out into luminous consciousness, and even throw into the shade of unconsciousness those other systems by which they had, for a long period, been eclipsed, and even extinguished. For example, there are cases in which the extinct memory of whole languages was suddenly restored; and, what is even still more remarkable, in which the faculty was exhibited of accurately repeating, in known or unknown tongues, passages which were never within the grasp of conscious memory in the normal state." Sir William then proceeds to quote, with approval, a few cases which illustrate the general principle. The first is on the authority of Dr. Rush, a celebrated American physician: