CH. xxix. ANIMAL ELECTRICITY. 259 



Philosophy at the University of Pavia, who was born at 

 Como in 1745, and was at this time a well-known natural- 

 ist. Not satisfied with merely reading about Galvani's ex- 

 periments, Volta tried them himself, and he began to suspect 

 that the electricity was not, as Galvani imagined, in the 

 frog's leg, but was produced by the two metals, copper and 

 iron, upon which the legs had been hung, and which were 

 acted upon by the moisture in the flesh. 



Then began a very famous controversy. Volta insisted 

 that the electricity came from the metals, Galvani that it 

 came from the animal. In each new experiment which 

 Galvani brought forward to prove his point, Volta still 

 showed that the electricity could be produced without the 

 animal, until at last Galvani succeeded in finding a test 

 which he thought must silence Volta for ever. He found 

 that by laying bare a nerve of the leg of a frog, called the 

 * crural nerve,' and bringing the end of it to the outside of 

 the muscles of the leg, he could produce the convulsions 

 without any metal at all. But Volta was not so easily con- 

 vinced ; he still insisted that it was the different fluids and 

 tissues being brought together which caused the electricity, 

 and that there was not a current running through the 

 animal. At this point, just when the truth would probably 

 have been worked out, Galvani died (in 1798), leaving 

 Volta in possession of the field ; and for twenty-eight years 

 no more was heard of animal electricity. We know now 

 that both the professors were right. Volta was right in 

 saying that the convulsions of the frog's legs on the balcony 

 were produced by the contact of the two metals in connec- 

 tion with a fluid ; while Galvani was right in saying that 

 there is an electricity in animals which acts without any 

 other help. In 1826 an Italian named Nobili repeated 

 Galvani's experiment, and having then an instrument called 

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