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the limbs were convulsed every time a spark was taked. Galvani, struck 

 with the phenomenon, made it a subject of inquiry, and found that metals? 

 applied to the nerves and to the muscles of these animals, determined 

 quick and strong contractions, when they were disposed in a certain man- 

 ner. He gave the name of Animal Electricity to this set of new pheno- 

 mena, from the analogy he thought he perceived between its effects and 

 those of electricity. The discovery was made public: many scientific 

 men, chiefly those of Italy, and Volta among others, were eager to make 

 additions to the labour of the inventor. The Medical Society of Edin- 

 burgh thought it right to take this point of physiology as the subject of 

 one of its annual prizes, which was adjudged to the work of Professor 

 Creve of Mentz, in which the term metallic irritation (irrllamentum me- 

 lallorum} is substituted for that of animal electricity. This new expres- 

 sion is essentially bad, since it implies that irritation by metals can alone 

 determine the galvanic phenomena, when charcoal, water, and many other 

 substances, produce them as well. The term of animal electricity has 

 been also laid aside, notwithstanding the great analogy between the effects 

 of electricity and those of galvanism, and this last name has been pre- 

 ferred, which, applying equally to the whole of the phenomena, immor- 

 talizes the name of the first observer*. 



To produce the galvanic phenomena, it is necessary to establish a 

 communication between two points of a series of nervous and muscular 

 organs. In this way there is formed a circle, of which one arc is com- 

 posed of the animal parts that are subjected to the experiment; while the 

 other arc is represented by the instruments of excitation, which consist 

 commonly of several pieces, some of them placed under the animal parts, 

 and called supports, and the others, by which the communication with 

 these is established, called communicators. 



To form a complete galvanic circle, take the thigh of a frog stripped of 

 its skin, detach the crural nerve down the knee, and apply it on a plate 

 of zinc; let the muscles of the leg lie on a plate of silver, then complete 

 the arc of excitation and the galvanic circle, by establishing a communi- 

 cation between the two supports with an iron wire, or copper, tin, or 

 lead: at the moment of touching the two supports with the conductor, 

 a part of the animal arc formed by the muscles of the leg, will be con- 

 vulsed. Although this arrangement of the animal parts, and of the gal- 

 vanic instruments, is the one most favourable to the production of these 

 phenomena, there is room for varying a good deal the composition of the 

 animal arc and the arc of excitation. Thus, you obtain contractions, by 

 placing the two supports under the nerve, and leaving the muscles with- 



* SUI.ZF.H, in the Memoirs of the Academy of Berlin, and in his " General Theory of 

 Pleasure" a work published in 1757, and inserted in 1769, in a collection published by 

 Bouillon, under the title of the " Temple du Honheur," tome III. p. 124, had mentioned, 

 that two plates of different metals being placed one above and another below the 

 tongue, and inclined towards each other at their extremities, at the moment when they 

 touched each other, he felt a sharp taste, which was frequently accompanied by a pecu- 

 liar faint light. COTUGNO had related in a Journal published at Bologna, in 1786, that 

 a student of medicine, while dissecting a living- mouse, was surprised to observe an elec- 

 tric movement of its limbs whenever the scalpel touched one of its nerves. It was not 

 until 1789, that GALVANI commenced his experiments. But he cannot be the less con- 

 sidered as the discoverer of this class of phenomena, even supposing that he knew the 

 experiments we have noticed, for their authors drew no conclusion from them ; while, 

 on the contrary, Galvani repeated, varied, and multiplied them, and was the first to. 

 contend for a species of electricity in the animal economy. 



