DISCOVERY OF VOLTAIC ELECTRICITY. 81 



The first announcement of Galvani's discovery in 

 1791 excited great notice, for it was given forth 

 as a manifestation of electricity under a new and 

 remarkable character; namely, as residing in the 

 muscles of animals 1 . The limbs of a dissected frog 

 were observed to move, when touched with pieces 

 of two different metals ; the agent which produced 

 these motions was conceived to be identified with 

 electricity, and was termed animal electricity ; and 

 Galvani's experiments were repeated, with various 

 modifications, in all parts of Europe, exciting much 

 curiosity, and giving rise to many speculations. 



It is our business to determine the character of 

 each great discovery which appears in the progress 

 of science. Men are fond of repeating that such 

 discoveries are most commonly the result of ac- 

 cident ; and we have seen reason to reject this 

 opinion, since that preparation of thought by which 

 the accident produces discovery is the most im- 

 portant of the conditions on which the successful 

 event depends. Such accidents are like a spark 

 which discharges a gun already loaded and pointed. 

 In the case of Galvani, indeed, the discovery may, 

 with more propriety than usual, be said to have 

 been casual ; but, in the form in which it was first 

 noted, it exhibited no important novelty. His frog 

 was lying on a table near the conductor of an elec- 

 trical machine, and the convulsions appeared only 



1 De Viribus Eleclricis in Motu Musculari. Comm. Bonon. 

 t. vii. 1792. 



VOL. III. G 



