Among the magic phenomena observed in magnetic sleep we must lastly mention ecstatic elevation in the air, the giving out of peculiar sounds, and the power to produce extraordinary effects at a distance. Even common somnambulists, it is well known, seem not to be in the same degree subject to the laws of gravity as persons in a state of wakefulness: hence their amazing exploits in walking on roofs, gliding along narrow cornices, or even running up perpendicular walls. Persons in magnetic sleep have been known to float on fresh water as well as in the sea, although they were unable to swim, and sank, if they went into the water when awake. Dupotel saw one of his patients running along the side of his room on a small strip of wood which was merely tacked on to the wall, and could not have supported a small weight. This peculiar power is all the more fully authenticated as persons have fallen from great heights, while in magnetic sleep, without suffering any injury; but if they are aroused, and then fall, they invariably become subject again to the natural laws, and are often killed. This temporary suspension of the law of gravity has been compared with similar phenomena in science. Thus it is well known that a galvanic stream passing through coils of copper wire will hold an iron needle suspended within the coils; and an iron ball dropped into a glass tube between two powerful magnets will in the same manner remain hanging free in the air. The advocates of this theory reason that if magnetism can suspend the law of gravity in metals, it is at least possible that it may have a similar power in the human body. It has, besides, been observed that certain affections, such as violent nervous fevers, increase the weight of sufferers considerably, while a state of trance diminishes it even more strikingly.