A D V E N T U R E S in C Y B E R S O U N DLuigi Galvani : 1737 - 1798
The Italian physician Luigi Galvani, b. Sept. 9, 1737, d. Dec. 4, 1798, achieved notoriety for his experiments on animal electricity, which led Alessandro Volta to the discovery of current electricity. Galvani was trained at the medical school at Bologna and after graduation practiced medicine and surgery, conducted physiological research, and taught medicine at Bologna. In 1780 he undertook carefully planned and executed experiments on the effects of static electricity on nerves and muscles. Using prepared frogs, Galvani observed continual muscle contractions when the spinal cords were connected by brass hooks to an iron railing. Galvani took this as confirmation of the theory that animal nerve and muscle tissue contained an electric fluid. Volta, however, later demonstrated that the electricity did not come from the animal tissue but rather from the different metals, brass and iron, coming into moist contact with each other. David Hounshell Source: The New Grolier Multimedia Encyclopedia
Background of Electrochemistry In 1791, a physician named Luigi Galvani discovered "animal electricity" in the bare nerve of a dissected frog's leg. He observed that the leg could be made to twitch if copper and iron, attached respectively to a nerve and a muscle, were brought into contact. Galvani believed that such intrinsic electricity was found only in living tissue. In 1800, it was discovered that, despite what Galvani had thought, electricity could have simpler origins. Alessandro Volta, using a stack of dissimilar metals placed in contact with moist paper, constructed the first battery, which was made up of consecutive plates of silver, zinc, and cloth soaked in salt solution. Later that year, William Nicholson and Anthony Carlisle used a similar battery to decompose water into hydrogen and oxygen. Many more electrolytic processes followed, one in 1807 that led to the discovery of potassium and sodium. Electrolyte processes are widely used today, mainly to obtain aluminum, chlorine, hydrogen, or oxygen.
The Italian physician Luigi Galvani, b. Sept. 9, 1737, d. Dec. 4, 1798, achieved notoriety for his experiments on "animal electricity," which led Alessandro Volta to the discovery of the electric battery. Galvani was trained at the medical school at Bologna and after graduation practiced medicine and surgery, conducted physiological research, and taught medicine at Bologna. In 1780 he undertook carefully planned and executed experiments on the effects of static electricity on nerves and muscles. Using prepared frogs, Galvani observed continual muscle contractions when the spinal cords were connected by brass hooks to an iron railing. Galvani took this as confirmation of the theory that animal nerve and muscle tissue contained an electric fluid. Volta, however, later demonstrated that the electricity did not come from the animal tissue but rather from the different metals--brass and iron--coming into moist contact with each other. However, a later experiment of Galvani's demonstrated animal tissue, without metal contact, as a source of electricity. How do ideas become accepted by the scientific community? How and why do scientists choose among empirically equivalent theories? A classic example is this famous Galvani-Volta controversy. This lively debate erupted when both scientists, each examining the muscle contractions of a dissected frog in contact with metal, came up with opposing but experimentally valid explanations of the phenomenon. Luigi Galvani, a doctor and physiologist, believed that he had discovered animal electricity (electrical body fluid existing naturally in a state of disequilibrium), while the physicist Alessandro Volta attributed the contractions to ordinary physical electricity. Their controversy derived from two basic, irreducible interpretations of the proper nature of a common domain: Galvani saw the frog phenomenon as the work of biological organs, Volta as that of a physical apparatus.
Dibner, Bern, Galvani-Volta: A Controversy That Lead to the Discovery of Useful Electricity (1952); Dunsheath, Percy, Giants of Electricity (1967).
Pera, M.: The Ambiguous Frog: The Galvani-Volta Controversy on Animal Electricity. Pera, M.; Mandelbaum, J., trans. Princeton University Press (1992)
Beginning with the electrical concepts understood by scientists in the 1790s, Pera traces the careers of Galvani and Volta and explains their laboratory procedures. The initial preference for Volta's theory, maintains Pera, depended not on clear-cut methodological rules, but on a dialectical dispute for which the renowned physicist was better equipped, partly because he shared the dominant metaphysical views of his time. Source: http://www.bmen.tulane.edu/~mweiss/BMEN619/Galvani.htm
Dal 1780 al 1790, l'insigne scienziato bolognese, Luigi Galvani, durante i suoi famosi esperimenti scientifici con le rane , si era piu' volte imbattuto nelle onde elettromagnetiche, senza pero' poterne prevedere l'esistenza, che venne divinata da Maxwell prima, e convalidata sperimentalmente da Hertz poi solo nel 1887.
 Galvani Coherer Source: http://www.geocities.com/CapeCanaveral/Lab/3248/predecessori.html
Galvani, Luigi (1737-98) Physiologist, born in Bologna, Italy. He studied at Bologna, where he became professor anatomy (1762). Investigating the effects of electrostatic stimuli applied to the muscle fibre of frogs he discovered he could also make the muscle twitch by touching the nerve with various metals without a source of electrostatic charge, and greater reaction was obtained when two dissimilar metals were used. He attributed the effect to 'animal electricity'. His worked inspired his friend Alessandro Volta, leading to the production of the electrical battery, and also initiated research into electrophysiology. The galvonometer is named after him.
Galvani, Luigi, Italian anatomist who discovered in 1771 that the muscles of dead frogs twitched when struck by a Spark from a machine. Furthermore, he found that they twitched whenever they came in contact with two different metals. He concluded that the twitching was evidence for the existence of "animal electricity," later shown to be erroneous by Alessandro Volta.
Noting that dissected frogs' legs twitched when touched by his scalpel, Luigi Galvani theorized that electrical impulses originated within the frog's body. Alessandro Volta recreated Galvani's experiments and drew a more accurate conclusion: the electricity was generated by the contact of dissimilar metals in a moist environment. Nevertheless, Galvani's theory of "animal electricity" captured the public imagination and continued to be defended until late into the 19th century.
The battery was invented in 1800 by Alessandro Volta a professor of physics in Como, Italy. He based his work on his friend Luigi Galvani who discovered that a dead frog twitched its leg muscles on contact with two different metals. Galvani thought that the frogs possessed electricity in their muscles but Volta thought believed (correctly) that the current was actually created by the two different metals, the muscles only detected it. Volta layed down layers of silver and zinc separating them with salty water and demonstrated a flow of electric current and as an indirect result, invented the battery.
Luigi Galvani (b. Sept. 9, 1737, Bologna, Papal States [Italy]--d. Dec. 4, 1798, Bologna, Cisalpine Republic), Italian physician and physicist who investigated the nature and effects of what he conceived to be electricity in animal tissue. His discoveries led to the invention of the voltaic pile, a kind of battery that makes possible a constant source of current electricity. Early years Galvani followed his father's preference for medicine by attending the University of Bologna, graduating in 1759. On obtaining the doctor of medicine degree, with a thesis (1762) De ossibus on the formation and development of bones, he was appointed lecturer in anatomy at the University of Bologna and professor of obstetrics at the separate Institute of Arts and Sciences. In 1762, also, he married Lucia, the only daughter of Professor Galeazzi of the Bologna Academy of Science, of which Galvani became president in 1772. Beginning with his doctoral thesis, his early research was in comparative anatomy--such as the structure of renal tubules, nasal mucosa, and the middle ear--with a tendency toward physiology, a direction appropriate to the later work for which he is noted. Galvani's developing interest was indicated by his lectures on the anatomy of the frog in 1773 and in electrophysiology in the late 1770s, when, following the acquisition of an electrostatic machine (a large device for making sparks) and a Leyden jar (a device used to store static electricity), he began to experiment with muscular stimulation by electrical means. His notebooks indicate that, from the early 1780s, animal electricity remained his major field of investigation. Numerous ingenious observations and experiments have been credited to him; in 1786, for example, he obtained muscular contraction in a frog by touching its nerves with a pair of scissors during an electrical storm. Again, a visitor to his laboratory caused the legs of a skinned frog to kick when a scalpel touched a lumbar nerve of the animal while an electrical machine was activated. Galvani assured himself by further experiments that the twitching was, in fact, related to the electrical action. He also elicited twitching without the aid of the electrostatic machine by pressing a copper hook into a frog's spinal cord and hanging the hook on an iron railing. Although twitching could occur during a lightning storm or with the aid of an electrostatic machine, it also occurred with only a metallic contact between leg muscles and nerves leading to them. A metallic arc connecting the two tissues could therefore be a substitute for the electrostatic machine. Electrical nature of nerve impulse Galvani delayed the announcement of his findings until 1791, when he published his essay De Viribus Electricitatis in Motu Musculari Commentarius (Commentary on the Effect of Electricity on Muscular Motion). He concluded that animal tissue contained a heretofore neglected innate, vital force, which he termed "animal electricity," which activated nerve and muscle when spanned by metal probes. He believed that this new force was a form of electricity in addition to the "natural" form that is produced by lightning or by the electric eel and torpedo ray and to the "artificial" form that is produced by friction (i.e., static electricity). He considered the brain to be the most important organ for the secretion of this "electric fluid" and the nerves to be conductors of the fluid to the nerve and muscle, the tissues of which act as did the outer and inner surfaces of the Leyden jar. The flow of this electric fluid provided a stimulus for the irritable muscle fibres, according to his explanation. Galvani's scientific colleagues generally accepted his views, but Alessandro Volta, the outstanding professor of physics at the University of Pavia, was not convinced by the analogy between the muscle and the Leyden jar. Deciding that the frog's legs served only as an indicating electroscope, he held that the contact of dissimilar metals was the true source of stimulation; he referred to the electricity so generated as "metallic electricity" and decided that the muscle, by contracting when touched by metal, resembled the action of an electroscope. Furthermore, Volta said that, if two dissimilar metals in contact both touched a muscle, agitation would also occur and increase with the dissimilarity of the metals. Thus Volta rejected the idea of an "animal electric fluid," replying that the frog's legs responded to differences in metal temper, composition, and bulk. Galvani refuted this by obtaining muscular action with two pieces of the same material. But the ensuing controversy was without personal animosity; Galvani's gentle nature and Volta's high principles precluded any harshness between them. Volta, who coined the term galvanism, said of Galvani's work that "it contains one of the most beautiful and most surprising discoveries." Nevertheless, partisan groups rallied to both sides. In retrospect, Galvani and Volta are both seen to have been partly right and partly wrong. Galvani was correct in attributing muscular contractions to an electrical stimulus but wrong in identifying it as an "animal electricity." Volta correctly denied the existence of an "animal electricity" but was wrong in implying that every electrophysiological effect requires two different metals as sources of current. Galvani, shrinking from the controversy over his discovery, continued his work as teacher, obstetrician, and surgeon, treating both wealthy and needy without regard to fee. In 1794 he offered a defense of his position in an anonymous book, Dell'uso e dell'attività dell'arco conduttore nella contrazione dei muscoli ("On the Use and Activity of the Conductive Arch in the Contraction of Muscles"), the supplement of which described muscular contraction without the need of any metal. He caused a muscle to contract by touching the exposed muscle of one frog with a nerve of another and thus established for the first time that bioelectric forces exist within living tissue. Last years On June 30, 1790, Galvani's devoted wife and companion died, childless, at the age of 47. In the last years of his life, Galvani refused to swear allegiance to the new Cisalpine Republic established by Napoleon. Thereupon he was dropped from the faculty rolls, and his salary was terminated. Rejecting help and much saddened, he moved into the old Galvani home in which his brother was living. Soon, however, the politicians recanted, and the professorship was again offered to Galvani without the requirement of an oath. But the affront had cut short his days: Galvani died in the house of his birth at age 61, at a time when the world was on the threshold of the great electrical revolution. Galvani provided the major stimulus for Volta to discover a source of constant current electricity; this was the voltaic pile, or a battery, with its principles of operation combined from chemistry and physics. This discovery led to the subsequent age of electric power. Moreover, Galvani opened the way to new research in the physiology of muscle and nerve and to the entire subject of electrophysiology. (B.Di.)
Luigi Galvani, Opere edite ed inedite del professore Luigi Galvani (1841) and Aggiunta, ed. by Silvestro Gherardi (1842), comprise a prime reference; Memorie ed esperimenti inediti di Luigi Galvani (1937), Galvani's laboratory notes; Commentary on the Effect of Electricity on Muscular Motion (1953), an English translation of Galvani's De Viribus Electricitatis in Motu Musculari Commentarius (1791), with facsimile of the Latin text, an introduction by I. Bernard Cohen, and an extensive bibliography; C. Mesini, Luigi Galvani (1958), a clear and scholarly modern study (in Italian).
Also see the extensive essay Electromagnetism & Life By Robert O. Becker and Andrew A. Marino and specifically Part 1: Chapter 1: The Origins of Electrobiology
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