Who discovered galvanism? - ACS Publications

the machine on the table and was simultaneously in contact with the ... and felt that she should be given credit for the discovery of galvanism rather...
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Who Discovered Galvanism? Luigi Galvani, after whom galvanism is named, was an Itdisn biologist who was studying the effect of an electric current on the nerves of skinned frog legs. The eleet,ricity czused the muscles to undergo conwlsions and the leg to twitch. According to encyclopedias, legend has i t that Galvani's wife, nee Lucia Galeazzi, daughter of s, teacher of anatomy under whom Galvani studied, was a woman of superior intelligence. One day as she was preparing frag legs far her husband's experiments she noticed that when her scalpel touched the metal of the machine on the tahle and was simultaneously in contact with the nerve of the frog leg, the leg twitched just as when an electric current was imposed. Galvani, in his writings, states that one of his assistants made this oh~ervation;and most encyclopedias seem to assume that Galvani's wife was that assistant. Over the years as I encountered many interesting aspects of galvanism relating to the corro~ioninside food cans, I developed a r e d admiration for Gdvani's wife as a result of her observation, and felt that she should be given credit for the discovery of galvanism rather than her husband. But this admiration received a severe shock from a lecture entitled "The Guide of Life" by C. J. Ducssse, professor of philosophy a t Brown University, as published in the January 1958 issue of Phi Beta. Kappa's Key Reporter. According to Ducas~e'sver~ion,Galvani's wife was a consumptive, and her physician prescribed broth from frog legs to strengthen her. One day as Galvani stood on his balcony which had an iron railing to prepare frog legs far his wife's broth, he hung the prepared legs on the railing with copper hooks. He observed the same muscular contraction and twitching that an electric current caused. This version of the discovery, I find, has received ridicule in the literature as being an old wives' tale: If Galvani were cooking for his wife, he would more likely be doing i t in the kitchen rather than in his laboratory or on his balcony. Moreover, why should he use copper hooks to hang the legs? To me, i t seems strange that a physician, whom one would assume t o be of a high order, would believe that the tremendous strength of frog legs would he an inherent property of the broth made from them. After all, Galvani was a biologist, and as such i t is doubtful that he would harbor such anotion. Neither Professor 3uc;tsse nor I have been able to find eonclusive evidence for the correctness of either of these stories. Recently I have checked through translations of Galvani's ,riginalpublieations dealing with this theme.

There is no doubt that Galvani studied the bimetallic effect on the nerves of m m y dead animals. He noted the effect of electricity produced by friction and electricity from a Leyden jar. He studied the effect of electricity fram lightning a t various distances and correlated this effect with the peals of thunder a t great distances. Of most significance was his ~ t u d yof what has been termed a "marine torpedo," an electric animal, perhaps what we know as an electric eel. After finding that many sources of electricity applied to the nerves of dead animals caused muscular contraction, he found that the electricity from the marine torpedo had the same effect. As a biologist, he was not diverted from his contention that he was observing animal electricity, "De Viribus Electricitatis." When there was no lightning and he hung frog legs with copper hooks on his iron railings, he felt that he had discovered atmospheric electricity. Probably his greatest achievement, as far as galvanism is concerned, was the aroueel of interest in Alessandro Volta. When Galvani's work first came to Volta's attention, the latter was inclined to accept Galvani's idea that the electricity involved was animal electricity. He interpreted i t as an upset in the amount of electricity in the muscle and in the nerve; the two metals served to complete the circuit and restore the balance. Rut as Volta experimented himself, he soon changed his mind. He first observed that when he placed a piece of tinfoil an his tongue in contact with a silver coin, there developed what he called a sourness. When he made his eye a. part of the circuit between two metals, i t created a. eensrttion of light just as a blow on the eye does. Volts. was soon convinced that the two metals were responsible for the electricity. Then began the heated argument that is mid to have led to the discovery of useful electricity. But the controversy was not between Galvani and Volta as is usually stated. Rather i t was between Volts. and Galvsni's nephew, Giovanni Aldini, professor of physics a t Bologna University. Galvani is reported to have tried to answer Volta. in only one publication. He seem8 never to have realized that. the electricity involving two metals results fram a change in one or both to produce electric energy. Gslvsni reported that an assistant first noted the bimetallic effect on frag legs, though there seems to he no record of the identity of the aseistant. I am quite willing to assume that the assistant wzs his wife. Edward F. Kohman 385 Kings Highway Cherry Hill, New Jersey

Volume 40, Number 12, December 1963

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