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GALVANISM, 



Galvanism is considered as electricity developed 

 by chemical action alone, without the aid of 

 friction. 



The first observation of its effects was owing to 

 an accident. The wife of Galvani in preparing 

 as a restorative a soup made of frogs, happened to 

 notice that the muscles of one of the frogs which 

 had been skinned, were thrown into violent con- 

 vulsions, when touched with a scalpel in the neigh- 

 bourhood of an electrical machine. Her husband 

 repeated the experiment, and found that the crural 

 nerve of a frog, or the nerves of any animal, was a 

 more delicate test of the presence of electricity 

 than of any other known substance, much more so 

 than Bennet's electrometer. 



He afterwards discovered that when the muscles 

 of a frog were in contact with one metal, and the 

 nerve in contact with a different metal, very violent 

 contractions were produced when the two metals 

 were made to touch each other, or were connected 

 by any substance which was a conductor of elec- 

 tricity. He also observed that some combinations 

 of metals w r ere more powerful than others, and 

 that zinc and silver had the most effect. 



Galvani supposed that some power of exciting 

 electricity existed in the muscles of the animal : 



