Biographical Sketch of Professor Volta. 3 



name of the Vulcanetto di Pietra Mala. Of these he published 

 a description, in which he first explained how these fires, as 

 well as those which spring from the ground near the ancient 

 city of Velleja, arise from the combustion of atmospheric air 

 disengaged from the ground. 



In 1782 Volta invented an electrical condenser for rendering 

 sensible small quantities of the electrical fluid ; and in the same 

 year he performed a tour through Germany, along with his 

 celebrated colleague M. Scarpa. After his friend parted with 

 him, he extended his tour to Holland, England, and France. 

 On his return from that journey he introduced into Lombardy 

 the culture of the potato, which he had observed in Savoy ; 

 and the peasants who first cultivated this valuable article of 

 food were rewarded with the prize offered by the Patriotic So- 

 ciety of Milan. 



The curious experiment of Galvani in 1790 on the electri- 

 city of the muscles of frogs gave a vigorous impulse to phy- 

 sical inquiry throughout Europe. Volta took a deep interest 

 in the new science to which Galvani's experiment has given 

 the name, and he had the good fortune to establish it on a 

 scientific basis, and to extend its boundaries by the most im- 

 portant discoveries and inventions. Valli, Fowler, and our 

 countryman Dr Robison, had preceded Volta in their galvanic 

 inquiries, and the latter had made a slight approach to the 

 invention of the pile, by discovering the sensation of taste 

 which was excited when the tongue was applied to the edges 

 of a number of plates of zinc and silver placed alternately upon 

 each other. 



The first researches of Volta were transmitted to the Royal 

 Society of London in 1793, in the form of two letters to Mr 

 Tiberius Cavallo, entitled Account of some discoveries made 

 J)y M. Galvani of Bologna, with experiments and observations 

 on them.* These letters contain a perspicuous account of the 

 discoveries of Galvani, with a notice of many curious experi- 

 ments of his own. He overthrows the opinion of Galvani, 

 that the animal body has an analogy to the Leyden phial ; he 

 found that two different metals were necessary to produce the 

 effect ; and he concluded that muscular contracti#is arise from 



* Phil. Trans. 1793, vol. Ixxxiii. p. \0, 



