33 S] G A L common salt, muriat of ammonia, or, more effectually, with nitre.-— The silver or copper may be pieces of money, and the plates of zinc may be cast of the. same size. A pile is then to be formed, by placing a piece of silver on a cor- responding one of zinc, and on them a piece of wet cloth, or card; which is to be repeated alternately, till the number required be ar- ranged in regular succession. But, as the pieces are apt to tumble down, if their numbers be consi- derable, unless properly secured, it will be advisable to support them by means of three rods of glass, or baked wood, fixed into a flat ■wooden pedestal, and touching the pieces of metal at three cqui-distant points. Upon these rods may be made to slide a small circular piece of wood, perforated with three holes, which will serve to keep the top of the pile firm, and the dif- ferent layers in close contacl. The moistened pieces should likewise be somewhat smaller than those of metal, and gently squeezed before they are applied, to prevent tl)e .superfluous moisture from insinu- ating itself between the pieces of metal —Thus constructed, the ap- paratus will afford a perpetual cur- rent of the animal-electric fluid, or Galvanic influence, through any conductor that communicates be- tween the uppermost and low- est plate ; and, if one hand be ap- plied to the latter, and the other to the highest metal, a shock will be perceived, which may be repeated as often as the. contact is renewed, This shock greatly resembles that giv< n by the torpedo, or gymnotus eleclricus : and, according to the
- size of the metallic plates,
the shock will be proportionally utfvngfZL. The intensity of the GAL charge, however, is so low, that it cannot penetrate the dry skin ; it Mill therefore be necessary to wet both hands, and to grasp a piece of metal in each, in order to produce the desired effeft : its power may be considerably increased, both by an elevation of temperature, and by augmenting the number of pieces that compose the pile. Thus 20 pieces of each will emit a shock, that is very perceptible in the arms j if 100 be employed, a very severe but tremulous and continued sen- sation will extend even to the shoulders ; and, if the surface of the skin be broken, the a<5tion of the Galvanic. influence will be un- commonly painful. The sensation of a flash, or shock with this apparatus, does not mate- rially differ from that produced by two simple plates ; but it may be effected in various ways, especially if one or both hands be applied in a wet state to the lowest plate of the pile ; or any part of the face be brought in contact with a wire communicating with the top piece. Partner, if a wire be held between the teeth, so as to rest upon the tongue, that organ, as well as the lips, will become convulsed, the flash will appear before the eye, and a very pungent taste will be perceived in the month. Many other curious facts June transpired on this interesting dis- covery ; but, as they have not been hitherto applied to medical purposes (though we believe that Gofvanism may be safely, and per- haps successfully, resorted to, in paralytic and other cases, where the muscles require excitement), we shall content ourselves with re- ferring the anions reader to Dr. i'wv ler's " Essay on Animal E/cc- trlcity," 8vOr; — lor a furthci ac- count.
