A.D. 1778.—Toaldo (Giuseppe) Abbé, celebrated Italian physicist, who had in 1762 been made Professor at the Padua University and was the first one to introduce the lightning rod in the Venetian States, makes known the merits of the last-named invention through his “Dei conduttori per preservare gli edifizj,” etc., which work embraces most of his previous treatises on metallic conductors as well as the translation of H. B. de Saussure’s “Exposition abrégée,” etc., Geneva, 1771, and of M. Barbier de Tinan’s “Considérations sur les conducteurs en général.”
The above was followed by many highly interesting memoirs containing valuable meteorological observations, notably those in continuation of the work of J. Poleni, made close up to the time of Toaldo’s sudden death at Padua, Dec. 11, 1798. His complete works, covering the period 1773–1798, were published in Venice through M. Tiato, with the assistance of Vincenzo Chiminello, during the year 1802.
References.—In addition to the last-named publication (entitled “Completa Raccolta d’ Opuscoli,” etc.), “Mem. della Soc. Ital.,” Vol. VIII. pt. i. p. 29 (“Elogio ... da A. Fabbroni,” 1799); note at Beccaria, p. 42 of Ronalds’ “Catalogue”; Larousse, “Dict. Universel,” Vol. XV. p. 251; “Biographie Générale,” Vol. XLV. p. 450; “Biografia degli Italiani Illustri,” etc., by E. A. Tipaldo, Vol. VIII; “Padua Accad. Saggi,” Vol. III. p. cv; “Opusc. Scelti,” Vol. VI. p. 265; Vol. VII. p. 35; “Nuovo Giornale Enciclopedico di Vicenza” for 1784; Antonio Maria Lorgna, “Lettera ... parafulmini,” 1778; G. Marzari (Vol. II. p. 73, of “Treviso Athenæum”); Fonda “Sopra la maniera ...” Roma, 1770; G. Marzari e G. Toaldo, “Memoria Descrizione ...” 25 Aprile, 1786; Barbier de Tinan, “Mémoire sur la manière d’armer,” etc., Strasbourg, 1780; F. Maggiotto’s letter to Toaldo upon a new electrical machine; Sestier et Méhu, “De la foudre,” etc., Paris, 1866.
Vincenzo Chiminello, nephew of Giuseppe Toaldo, whom he succeeded at the Padua Observatory and who continued the Giornale Astro-meteorologico after his uncle’s death, is the author of works on the magnetic needle, on lightning conductors, etc., which are treated of in the columns of the Mem. Soc. Ital., Vols. VII and IX; the Giornale Astro-met. for 1801, 1804, 1806, as well as in the Saggi ... dell’Accad. di Padova, Nuova Scelta d’Opuscoli, and Opuscoli Scelti sulle scienze e sulle arti.
References.—Chiminello’s biography, Giorn. dell’Ital. Lettera, etc., Serie II. tome xvii. p. 164, and in “Atti della Soc. Ital.,” Modena, 1819.
A.D. 1778.—Dupuis (Charles François), eminent French writer who, at the age of twenty-four, became Professor of Rhetoric at the College of Lisieux, constructs a telegraph upon the plan suggested by Amontons (at A.D. 1704). By means of this apparatus he exchanged correspondence with his friend M. Fortin, then residing at Bagneux, until the commencement of the Revolution, when he deemed it prudent to lay it permanently aside (Encyclopædia Britannica, 1855, Vol. VIII. p. 263).
A.D. 1778.—Brugmans—Brugman (Anton), who was Professor of Philosophy at the University of Francker between 1755 and 1766, publishes his “Magnetismus, seu de affinitatibus magneticis.” He is, besides, the author of several works upon magnetic matter and the magnetic influence, which appeared 1765–1784 and are alluded to by Poggendorff (“Biog.-Liter. Hand.,” Vol. I. p. 316), as well as in the “Vaderlandsche Letter” for 1775 and 1776, and at p. 34, Vol. I of Van Swinden’s “Recueil de Mémoires ...” La Haye, 1784.
It was in this same year, 1778, that Sebald Justin Brugmans—Brugman—son of Anton Brugmans, a distinguished physician, naturalist and author who was the successor of Van Swinden at the Francker University, and became Professor of Botany at Leyden, discovered that cobalt is attracted while bismuth and antimony are repelled by the single pole of a magnet, thus laying the foundation of the science of diamagnetism.
Humboldt remarks: “Brugmans, and, after him, Coulomb, who was endowed with higher mathematical powers, entered profoundly into the nature of terrestrial magnetism. Their ingenious physical experiments embraced the magnetic attraction of all matter, the local distribution of force in a magnetic rod of a given form, and the law of its action at a distance. In order to obtain accurate results the vibrations of a horizontal needle suspended by a thread, as well as deflections by a torsion balance, were in turn employed.”
References.—“Biographie Générale,” Vol. VII. p. 582; Larousse, “Dict. Univ.,” Vol. II. p. 1334; “Catalogue Sc. Papers Roy. Soc.,” Vol. I. p. 672; W. H. Wollaston, “Magnetism of ... Cobalt and Nickel” (Edin. Phil. Jour., Vol. X. p. 183); Kohl on pure cobalt (L. F. F. Crell’s “Neusten Ent.,” Vol. VII. p. 39); Tyndall, “Researches on Dia-Magnetism,” London, 1870, pp. 1, 90, etc.; Appleton’s Encyclopædia, 1870, Vol. IV. p. 10; Humboldt’s “Cosmos,” 1859, Vol. V. p. 61; Augustin Roux, “Expériences nouvelles ...” (Journal de Médecine, for November 1773). Consult also, for Sebald J. Brugmans, “Biog. Générale,” Vol. VII. p. 582; Bory de Saint Vincent, in the “Annales Générales de Sciences Physiques,” Vol. II.