Matteucci, Carlo

views updated

MATTEUCCI, CARLO

(b. Forli, Italy, 2 June 1811; d. Leghorn, Italy, 24 June 1868)

physiology, physics.

The son of Vincenzo Matteucci, a physician, and Chiara Folfi, Matteucci attended the University of Bologna from 1825 to 1828, when he graduated with a degree in physics. At the age of sixteen he prepared his first published paper, on meteorology.

In October 1829 Matteucci went to Paris, at his father’s expense, and spent eight months attending scientific lectures at the Sorbonne. He returned to Forlî in June 1830. He received his first academic appointment in 1840, when he was appointed professor of physics at the University of Pisa on the advice of Alexander von Humboldt. In the meantime he carried out electrophysiological investigations, first at his father’s home and later in a small laboratory in Ravenna. His reports, presented to the Académie des Sciences by Arago and Edmond Becquerel, made his “name known through the European Continent,” as Faraday wrote when Matteucci was only twenty-two. In 1842, at Pisa, he made his most famous discovery, the induced twitch, and began publishing his works in English, with a series of memoirs sent to the Royal Society.

A liberal, Matteucci was involved in the great political upheaval of 1848, which spread through most of the Continent. He was sent by the new Tuscan government to the Frankfurt Parliament, with the aim of establishing contacts with the German liberals. He did not lose his chair of physics after the restoration; in fact, the grand duke of Tuscany gave him—a political adversary—the funds necessary to build the first large institute of physics. When Italy was united, Matteucci became a senator for life and in 1862, as minister of education, reorganized the Scuola Normale Superiore of Pisa as the first Italian institute for advanced studies.

Working on torpedoes, Matteucci found that the discharges of the electric organ of the fish were due to impulses arising in the fourth lobe of the medulla, which he called the electric lobe. Mechanical or galvanic stimulation of this lobe constantly produced the electric discharge, the sign of which was not reversed when the direction of the stimulating current was reversed. This discharge could also be produced reflexly by applying pressure to the fish’s eyes or by stimulating its body. Both spontaneous and induced discharges occurred after ablation of the cerebral hemispheres, of the optic lobes, and the cerebellum; but they could not be observed after bilateral ablation of the electric lobe.

The existence of the phenomenon of animal electricity had already been definitely proved with Galvani’s last experiment (1797), and it is now clear that the twitch he produced was due to the currents of injury of sciatic nerve fibers, a phenomenon made possible by the polarization of their intact membranes. It remained for Matteucci to prove in 1842 that a current could constantly be detected when the electrodes of the galvanometer were placed in contact with the intact surface and with the interior (wounded portion) of a muscle. That the wounded part was always negative with respect to the normal surface was later demonstrated by Emil du Bois-Reymond, who in 1843 confirmed Matteucci’s observation.

Although in 1838 Matteucci had recognized that the frog’s resting potential (the difference in potential between the interior and exterior of a muscle fiber at rest) was, psradoxically, abolished by strychnine tetanus, it remained for du Bois-Reymond to demonstrate in 1848 that during the muscle contraction there was a “negative variation” of the injury currents. Just a year before the first preliminary note by du Bois-Reymond (1843), however, Matteucci had presented to the Académie des Sciences his report on the “induced twitch.” In an experimental demonstration he gave at Paris in the presence of Humboldt and of several members of the Academy, he showed that when the sciatic nerve of the galvanoscopic frog leg was placed upon the leg muscle of another frog, the contraction of the latter muscle “induced” the contraction of the galvanoscopic leg. Becquerel immediately repeated and confirmed this experiment and gave the correct interpretation: that the nerve of the galvanoscopic leg was stimulated by the action currents of the contracting muscle of the other frog. Matteucci accepted this interpretation but failed to see the relation between his discovery and the phenomenon of the negative variation. This was done for the first time in Johannes Müller’s Handbuch der Physiologie des Menschen (1844) and in du Bois-Reymond’s Untersuchungen über thierische Electricität 1848–1849).

Although Matteucci was scientifically active until the end of his life, his most important work in physiology was carried out between 1836 and 1844 on the neural mechanisms of the electric discharge of torpedoes on the resting potential of the frog’s muscle, and especially on the action currents, which he discovered. His reluctance to admit that an electric phenomenon could disappear as a consequence of an active physiological process (the “negative variation”) led Matteucci in 1845 to reject his own galvanometric findings of 1838 and Becquerel’s interpretation of the induced twitch. This was the major error in the life of an outstanding scientist, whose work greatly influenced nineteenth-century electrophysiology.

BIBLIOGRAPHY

A list of 269 papers written by Matteucci is in Royal Society Caṫalogue of Scientific Papers, IV, 285–293; VIII, 354–355. His major books are Essai sur les phénomènes électriques des animaux (Paris, 1840); and Traité des phénomènes électro-physiologiques des animaux (Paris, 1844).

On Matteucci and his work, see N. Bianchi, Carlo Matteucci e l’Italia del suo tempo (Turin, 1874), with a complete bibliography of his works; and G. Moruzzi, “L’opera elettrofisiologica di Carlo Matteucci,” in Physis, 6 (1964), 101–140, with a partial listing of his works and bibliography of secondary literature.

Giuseppe Moruzzi

About this article

Matteucci, Carlo

Updated About encyclopedia.com content Print Article