Frog’s legs

He made an ingenious but erroneous explanation. Volta set to work to find the true cause of this animal electricity. Slowly he came to believe that the electricity produced belonged to the metals and not to the frog s legs. He proved it to the astonishment of the scientific world. Furthermore, he made good use of his discovery. By connecting a series of two dissimilar metals, zinc and silver, separated by a piece of doth moistened in a solution of salt, he obtained a weak electric current. He joined a larger series of these metals and obtained... 

Galvani, his adventure with a frog s legs. 1 Gamboa-Aldeco, on the compression of ions in the double layer, 190 Gamma functions, some properties, 755 Gas phase... 

Alessandro Volta, Italian physicist, discovered why the frog s leg twitched. He built the first battery (voltaic pile) of stacked Ag-Zn plates separated by paper or cloth soaked in saltwater. 

Galvani concluded that the electric fluid was already present in the frog s legs and that the metals merely served to release it, just as pipes can draw off water from tanks or reservoirs. 

The muscular contraction of a frog s legs by contact with copper and silver wires was noticed in 1658 by Jan Swammerdam. Sulzer found that when a plate of lead and one of silver laid on the tongue touch one another, a vitriolic taste is perceived the cause is a vibratory motion of the metals which is communicated to the nerves of the tongue. He does not connect the phenomenon with electricity. 

In the third letter (24 October 1795) Volta says a weak motion of frog s legs is produced by contact with different liquids (blood, mucus, urine, salt... 

In this experiment, a procedure is given for the preparation of a local anesfhefic, benzocaine, by fhe direcf esferification of p-aminobenzoic acid wifh ethanol. At the instructor s option, you may test the prepared anesthetic on a frog s leg muscle. 

Note to the Instructor Benzocaine may be tested for its effect on a frog s leg muscle. See Instructor s Manual for instructions. 

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