Sensitiveness is a faculty pertaining to the spiritual nature, and is acute in proportion as that spiritual nature dominates the physical senses. It is possessed by all, and by a few in a remarkable degree. It is variable in the same individual, is often the result of drugs, of fatigue, of sleep, and may be induced or intensified by hypnotism or mesmerism. It may manifest itself suddenly and at long intervals, once only in a lifetime, or be a steadfast quality. It may have all degrees of acuteness, from impressibility scarcely distinguishable from the individual’s own thoughts, to the purest independent clairvoyance. CONDITIONS AND ILLUSTRATIONS OF SENSITIVENESS.--For one mind to influence another, the two must be in harmony, at least in certain points. The thought vibrations in one will not otherwise awake like vibrations in the other. Take for illustration two musical strings, one with fixed attachments, and the other with a moveable bridge or stop. Now if the first be set in vibration, the other, being on a different key, will not respond in unison, but the stop will slightly move; and if the vibrations continue, the stop will move forward until the exact length of chord is attained, and then both strings will vibrate in harmony, one repeating the notes of the other. If an hundred musical instruments were placed in a room, only two of which were tuned alike, if one of these were touched, its mate would respond, but the others would remain silent. These thought vibrations may be received suddenly like a flash, as in the case of premonitions and warnings of danger, the sensitive state lasting but a brief time; or it may be cultivated and become permanent with the individual. The hypnotic, or somnambulic subject, may be more or less affected at first, and slowly fall under the influence, until the continuous condition is the same as that in which a premonition is received. As an illustration of the method by which this is accomplished, whether the operator be a spirit clad in a physical or in a celestial body, the improvements by age and use of the violin may be taken.