SciCombinator

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Concept: Luigi Galvani

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During the 1790s, Alexander von Humboldt (1769-1859), who showed an early interest in many facets of natural philosophy and natural history, delved into the controversial subject of galvanism and animal electricity, hoping to shed light on the basic nature of the nerve force. He was motivated by his broad worldview, the experiments of Luigi Galvani, who favored animal electricity in more than a few specialized fishes, and the thinking of Alessandro Volta, who accepted specialized fish electricity but was not willing to generalize to other animals, thinking Galvani’s frog experiments flawed by his use of metals. Differing from many German Naturphilosophen, who shunned “violent” experiments, the newest instruments, and detailed measurement, Humboldt conducted thousands of galvanic experiments on animals and animal parts, as well as many on his own body, some of which caused him great pain. He interpreted his results as supporting some but not all of the claims made by both Galvani and Volta. Notably, because of certain negative findings and phenomenological differences, he remained skeptical about the intrinsic animal force being qualitatively identical to true electricity. Hence, he referred to a “galvanic force,” not animal electricity, in his letters and publications, a theoretical position he would abandon with Volta’s help early in the new century.

Concepts: Fish, Battery, Galvanic cell, Alexander von Humboldt, Luigi Galvani, Alessandro Volta, Galvanism, Voltaic pile

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Scribonius Largus, the court physician for the Roman emperor Claudius, used an electrical torpedo fish in 50 A.D. to treat headaches and gout. More than 1000 years elapsed before the idea of therapeutic brain stimulation was rekindled. In 1786, Luigi Galvani demonstrated that he could conduct electricity through the nerves in a frog’s leg. Later, Alessandro Volta conducted electrical current through wires and built crude but effective battery sources. Yet none of these experimenters could have predicted the usefulness of their technology in treating human disease by applying an electrical current within the human brain. This year’s Lasker-Debakey Clinical Medical . . .

Concepts: Medicine, Battery, Galvanic cell, Volt, Roman Empire, Luigi Galvani, Alessandro Volta, Claudius

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To truly understand the potential value of using a carbon ion beam to treat atrial fibrillation requires a brief historical review of the treatment of symptomatic bradycardia with pacemakers. In 1580 Geronimo Mercuriale found and reported that a slow pulse rate was associated with syncope.(1) Over two hundred years later, Luigi Galvani in 1791 reported that electricity was innate in organic tissue in a series of studies involving stimulation of frog leg muscles with electrically charged brass hooks placed in the spinal cord.(2) He also reported cardiac contractions with similar electrical stimulation in a frog heart. Approximately 10 years later Alessandro Volta created the first battery that could create electricity independent of electrostatic machines. In 1856, Rudolph Albert von Kollicker showed that each frog heart beat was the result of electrical stimulus.(3) In 1887 Augustus Desire' Waller reported that each heartbeat begins at one point of the organ and propagates to the other end.(2) This article is protected by copyright. All rights reserved.

Concepts: Electric charge, Cardiology, Heart, Heart rate, Battery, Galvanic cell, Luigi Galvani, Alessandro Volta

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After extensive experimentation during the 1790s, Alexander von Humboldt remained skeptical about “animal electricity” (and metallic electricity), writing instead about an ill-defined galvanic force. With his worldview and wishing to learn more, he studied electric eels in South America just as the new century began, again using his body as a scientific instrument in many of his experiments. As had been the case in the past and for many of the same reasons, some of his findings with the electric eel (and soon after, Italian torpedoes) seemed to argue against biological electricity. But he no longer used galvanic terminology when describing his electric fish experiments. The fact that he now wrote about animal electricity rather than a different “galvanic” force owed much to Alessandro Volta, who had come forth with his “pile” (battery) for multipling the physical and perceptable effects of otherwise weak electricity in 1800, while Humboldt was deep in South America. Humboldt probably read about and saw voltaic batteries in the United States in 1804, but the time he spent with Volta in 1805 was probably more significant in his conversion from a galvanic to an electrical framework for understanding nerve and muscle physiology. Although he did not continue his animal electricity research program after this time, Humboldt retained his worldview of a unified nature and continued to believe in intrinsic animal electricity. He also served as a patron to some of the most important figures in the new field of electrophysiology (e.g., Hermann Helmholtz and Emil du Bois-Reymond), helping to take the research that he had participated in to the next level.

Concepts: Electricity, Fish, Eel, Electric eel, Alexander von Humboldt, Luigi Galvani, Alessandro Volta, Voltaic pile