Carlo Matteucci and the Legacy of Luigi Galvani

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Carlo Matteucci and the Legacy of Luigi Galvani Archives Italiennes de Biologie, 149 (Suppl.): 3-9, 2011. Carlo Matteucci and the legacy of Luigi Galvani M. BRESADOLA Department of Humanities and Neuroscience Center, University of Ferrara, and National Institute of Neuroscience, Italy A bstract Carlo Matteucci (1811-1868) is considered one of the founders of electrophysiology, thanks to his research on electric fish, nerve conduction, and muscular contraction. In this essay Matteucci’s early investigation into life pro- cesses is discussed in the context of the debates on Galvanism, a new scientific field inaugurated by the discovery of animal electricity made by Luigi Galvani in the 1790s. Matteucci rejected both a “physicalist” and a “vitalist” interpretation of the phenomena of Galvanism, adopting instead the same view which had guided Galvani in his research on animal electricity. In this regard, Matteucci can be considered the true scientific heir of Galvani. Key words Matteucci, Carlo • Galvani, Luigi • Galvanism • History of electrophysiology Introduction of Moruzzi’s article; instead, I shall focus on some minor works which Matteucci published in the early In an article published in 1964, which still remains 1830s, in the period that preceded his major discov- the most relevant study of Carlo Matteucci’s sci- eries. My aim is to reconstruct the context in which entific work, Giuseppe Moruzzi claimed that “the Matteucci’s electrophysiological research began, electrophysiological work to which [Matteucci] owes and to identify some interests and motives which imperishable fame begins in 1836” (Moruzzi, 1964; guided Matteucci in his scientific investigation. To English translation in Moruzzi, 1996, p. 70). It was this end I shall examine the content of two papers in that year, in fact, that Matteucci identified the ner- which Matteucci published in 1830 and which vous centres responsible for the electrical discharge concerned some phenomena that were included in of Torpedo. Then, in 1838, he published some fun- the realm of Galvanism; then I shall outline a brief damental research on the electrical nature of muscle history of Galvanism in the first three decades of contraction and nerve conduction, which brought the 19th century, in order to highlight the multiple him within a few years to discover the muscle demar- meanings of this term in different disciplinary and cation current and the action current. He also made cultural contexts; and finally, I shall identify the an observation of capital importance, the “nega- connection between Matteucci’s early investiga- tive Schwankung” (the negative oscillation), which, tion and a specific tradition of Galvanism. This correctly interpreted by du Bois Reymond, marks tradition retained the fundamental aspects of the the “beginnings of modern electrophysiology”, as work of Luigi Galvani while developing them by Moruzzi wrote in his article (Moruzzi, 1996, p. 84). adopting new instruments such as the battery and In my paper I shall not discuss Matteucci’s contri- the galvanometer. In this regard, Matteucci can be bution to electrophysiology, which was the topic considered the scientific heir of Galvani and his Corresponding Author: Marco Bresadola, Department of Humanities and Neuroscience Center, University of Ferrara, and National Institute of Neuroscience, Italy - Tel.: +39 0532 293412 - Email: [email protected] 4 M. BRESADOLA work the fulfilment of Galvani’s investigation into By the 1830s, however, Galvanism was not limited animal electricity. to the repetition of Galvani’s and Volta’s experi- ments, but included, more generally, all the research made on the effects of electricity on animal tis- Matteucci’s 1830 papers sues. In this regard a second paper published by Matteucci in 1830 also belonged to the realm of The first electrophysiological work published by Galvanism, even though it did not derive directly Matteucci is a brief Memoir which appeared in from Galvani’s research. It appeared in an impor- Forlì, his native city, in November 1830. Matteucci tant scientific journal, the Annales de Chimie et was only nineteen years old, and he had just returned de Physique, some months before the one I have from a one-year period of study spent in Paris, just discussed. The journal was edited by François where he had established friendly relationships Arago and Joseph Louis Gay-Lussac, and it was a with prominent scientists such as François Arago point of reference for all chemists and physicists of and Antoine César Becquerel (the grandfather of the time, especially in the investigation of the phe- the discoverer of radioactivity) (Bianchi, 1874). In nomena related to the battery. In this paper, which this work Matteucci focussed on muscular contrac- he published during his stay in Paris, Matteucci tions that could be observed in an animal when the reported some experiments aimed at testing “the electrical circuit in which it was included, was inter- analogy between [bodily] secretions and electro- rupted. This observation had been made a long time chemical decompositions” (Matteucci, 1830a, p. before, but it had received a renewed attention in 256). He had applied a battery of fifteen elements to the previous years thanks to two Italian scientists, the peritoneum, liver and other secretory organs of Leopoldo Nobili and Stefano Marianini (Mazzolini, rabbits and other animals, obtaining different liquids 1986). Matteucci confirmed the observations made at the two opposite poles. From these experiments by Nobili and Marianini, but criticized Marianini Matteucci concluded that the analogy between the for his explanation in terms of a condensation of process of biological secretion and that of electro- the electric current in the neuro-muscular system. chemical analysis rested on positive evidence, and Instead, for Matteucci the contractions depended on he proposed a research programme aimed at estab- the structure of muscular and nervous fibres, which lishing the “electrical state [l’état electrique] of the reacted to the action of the electric stimulus by secretory organs” (Matteucci, 1830a, p. 258). From shortening and relaxing (Matteucci, 1830b). Matteucci’s words in this paper, as well as in the one I shall return to Matteucci’s interpretation, as it on muscular contractions, the idea thus emerges that implies a particular view of vital phenomena which electricity had an active role in vital phenomena, he developed from the very beginning of his scien- and that Galvanism was a fruitful tool for exploring tific career. What I would like to stress here is that fundamental life processes like secretion and animal Matteucci placed the topic of his Memoir in a specif- motion. But what did Galvanism exactly mean for ic field, which he called “the science of Galvanism” Matteucci and his contemporaries? (Matteucci, 1830b, p. 1). In fact, the observation of muscular contractions occurring when an electrical circuit was interrupted, had been already made by Galvanism in the early 19th century Luigi Galvani and Alessandro Volta in the 1790s, during the controversy on animal electricity opened Around 1830 the term Galvanism was used in dif- by Galvani’s publication of his De viribus elec- ferent disciplines and with different meanings. In tricitatis in motu musculari (1792) (Bresadola, 1998; a popular textbook on natural philosophy we find Piccolino and Bresadola, 2003; Pancaldi, 2003). But, it included in the part devoted to electricity. Here while Volta’s merit as an early observer of the phe- Galvanism meant both a way to produce electricity, nomenon was recognized by Matteucci’s contempo- mainly through the use of the battery, and a natural raries, Galvani’s was not, a clear sign of the uneven agent with a problematic relation to electricity: “It reception that the work of these two great men of is remarkable – we read in a section of this book – science had in the first decades of the 19th century. that among the many strong resemblances between Carlo Matteucci AND THE legacy OF LUIGI Galvani 5 electricity and galvanism, we nowhere find a perfect was used in the study of animal motion and other accordance” (Fischer, 1827, p. 201). Electricity and vital processes, and it was applied to the treat- Galvanism were, instead, kept completely separated ment of diseases, inaugurating the field of medi- in chemistry textbooks such as the popular Elements cal Galvanism. But the battery also contributed to of chemistry by Edward Turner, in which Galvanism the emergence of novel scientific disciplines, like was treated as one of the “imponderable substances” electro-magnetism, thermo-electricity and electro- existing in nature, along with caloric, light, and chemistry, which initially retained important con- electricity (Turner, 1827). But Galvanism appeared nections with Galvanism. For instance, the title of also in medical books, especially with regard to the George Singer’s textbook Elements of electricity treatment of some pathologies through the use of and electro-chemistry was translated into French instruments such as the battery (Morus, 1992). as Élémens d’électricité et de galvanisme, show- The epistemological status of Galvanism, at the same ing a clear overlap between electro-chemistry and time ubiquitous and ambiguous, reflected its history Galvanism (Singer, 1817). In fact, the investigation in the early decades of the 19th century (Bresadola of the chemical effects of the application of the bat- and Pancaldi, 1999). It is difficult to establish who tery to organic and inorganic substances became an first introduced
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