CAVALLO iTreerisva), an electrician and natiw ml philosopher ; been at Naples 30th March 174g ; and son of a physician established in that city.
His father died when he was only eleven years old ; but he received • liberal education through dm kindness ofhis friends, and completed his smdies at the University of Naples. He was originally des' tined for commerce, and mare to England in 177t, in order to obtain more complete information re., 'pleating the various objects of mercantile pursuit. Bet he soon abandoned his intention of adopting that mode of life; and determine& to devote his time almost endasively to- the cultiration of science, and to literary employments connected with it.. The splendid improvements which had been lately made fir electricity, easily directed his earliest retention to that amusing department of natural philosophy; but his studies were by no means confined to that sub ject; and the extent of his diversified researches may be underseas& from an enumeration of his prin cipal publications.
1. Extraordinary Electricity of the Atmoopkere in October 177 5. Phil. Trans; 1776, p. 407. This observadea wee made at Islington, where the author then resided ; and he seems to hose been in some danger of becoming, like another Richman, a mar tyr to his zeal, in pursuit of his favourite ; for he says that he felt &number of severe shocks, while he was holding the wire of his kite.
2. An account of some new Electrical Experiments. Phil. Tram. 1777, p: 48,.. He here describes two atmospherical electrometers* and an exhausted • tube containing some quicksilver, ihr illustrating the na ture of electrical excitation. A paper of Mr Henly, in the snitie volume, contains also some commteaa. times from Mr Cavallo, and in particular a remark on the opposite electricities which he detected in the bow and strings of hie violin.
S. New Electrical Experiments. .Phil. Trans, 1777, p. 388. Relating to changes of the colours of pigment*, with a description of a pecks electrol. meter.
don, 1777. German by Goblet, Live. Leipz. 1785. French by &Whore, 8vo. Paris,1785. Ed. 4, 8 vols. ego. Loadon, 17045.
This Essay contains a clear and familiar account of the principal facts respecting electricity, which had been discovered et the time of its publication, as well as of the best apparatus and of the most in teresting experiments. The first part relates to the general laws •of the science ; the second to the hypo. thetical theories, by which different authors have at tempted to explain them, but without any mention of the calculations of Alpine"' and Caveediahr; the part giver; an account of the practical arrangement of electrical apparatus, and the fourth of some ori ginal experiments and instruments; the fifth part in the later editions, is a republication of.the author's Essay on Medical Electricity. To the fourth edi tion a third volume is added, containing an account of the recent discoveries respecting animal eleotrici. ty ; of the author's multiplier, for detecting the pre. mace of small quantities of electricity, by the se. peated operation of two condensers connected toga. thee; and df mine original- and very important ex periments, relating principally So the effect of the contact of different metals with mob other, and ex hibiting an imperfect outline of those which have since furwished Volta and Davy with their idgesiout explanations of the phenomena of the electrochemical. battery.
Mr Cavallo has inadvertently attributed to Nollpt the honour of having first entertained the opinion of site electrical nature of thunder and lightning i the German trandater has• thought it necessary to via. &mar the scientific character of his own country,by, laying claim to this conieeture on behalf of Winkler, but Mr Siivettre has remselaid, with el laudable that both Germany and Female natant on this occasion• give way to England, since she first suggestion of-the identity is found in a paper of Stephen Gray, published in the Philosophical Tram actions about 1735.