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XV. Letter from A. M. Vasalli-Eaxdi to J. BuviNA, 



ProfeJJbr of Medicine in the Univcrjity of Turin, on Animal 

 Bleclricity'- . 



1 HE electric phenomenon which vou obferved in my 

 electrometer, placed on the back of a difeafed animal at the 

 moment of its being attacked by a fit of flnvering, appears 

 to me to be a neceffary confequence of the general theory 

 of eleclricity, and of the modifications which it experiences 

 in the animal economy. The following is the manner in 

 which, I think, I have proved in my letter on the origin of 

 animal eleclricity, that man, in the fiate of health, like all 

 other animals, has parts pofitively electric, while others are 

 negatively fo. 



It appears that, in the animal, the negative part, that of 

 the excretions, is not fo ftrong as the politive part, that of 

 the blood. But if the change of the animal economy de- 

 ftroys the natural boundaries of electricity in the body, on 

 account of the tendency of the latter to bring itfelf into 

 equilibrium, it ought to efcape and to manifeft itfelf exactly 

 at the moments when the boundaries are deftroyedf ; that 

 is to fav, when the virus changes the internal parts, which 

 is proved by the fits of fhivering : fear and other violent paf- 

 fions, as they change the animal economy, ought alfo to 

 produce the fame effect. Thus you have feen the firings of 

 my electrometer, placed on the back of the animal, feparate 

 from each other, either during the fits of fhivering occa- 

 fioned bv a contagious difeafe, or during thofe produced by 

 fear; vou fee that the fame theory explains alfo the want of 

 electricity which you obferved in difeafed cats. I am per- 

 fuaded that this want will in no cafe exilt till the difeafe has 

 continued feveral days, and the animal economy has become 

 deranged. When I concluded my electric experiments on 

 water and ice J, f repeated them on feveral liquids, animals:, 



' Fr<>;n the Journal de Pbyfique, Plijviofe, an. 8. 

 •) Jo < vftque, Metijdor, an. 7. 



i ''.' j .''■• & i| Vol. in. 



Z ? and 



