It is probably a feature connected with this insensibility that persons in magnetic sleep can with impunity take unusually large doses of medicine, which they prescribe for themselves. For magnetic sleep seems to develop, as we have stated, among other magic phenomena, a peculiar insight also, into diseases and their remedies. Although diseases may assume a variety of deceptive forms, the predictions made by magnetic patients, many months in advance, seldom fail to be verified. This is a mere matter of instinct, for ignorant persons and young children possess the gift in equal degree with the best-informed and most experienced patients. The remedies are almost exclusively so-called simples--a hint of some value to physicians--but always prescribed with much judgment, and in a manner evincing rare medical tact. The dose, however, is generally twice or three times as much as is ordinarily given. Magnetic patients prescribe as successfully for others, with whom they are placed _en rapport_, as for themselves, since a state of perfect clairvoyance enables them to judge of other persons also with perfect accuracy. One of the most remarkable cases is mentioned by Schopenhauer. ("Parerga," etc., I. p. 246.) A consumptive patient in Russia directed, in her magnetic sleep, the attending physician to put her for nine days into a state of syncope. He did so reluctantly, but during this time her system seemed to enjoy perfect rest, and by this means she recovered. Haddock, also, cured several persons at a distance, by following the directions given to him by a patient of his in her magnetic sleep; he handed her a lock of hair, or a few written lines, which sufficed to put her _en rapport_ with the absent sufferers.