1^ Volta on Animal EleSinclfjT. 



other experiments of the like kind, form the chief fubje^l of 

 my firft letter to the Abbe ValfaU, Profeffor of Natural Phi- 

 lofophy at Turin, written in the beginning of the year 1794, 

 and afterwards publiflied with the other in Brugnatelli's 

 Journal. 



If filver be lefs expofed to he attacked by faline and other 

 fluids (except by liver of fulphur, which inftantaneoufly 

 renders it black); if it be lefs fufceptible of confiderable and 

 lading variations, and has therefore this advantage over other 

 metals, that it is liable to fewer irregularities ; tin, on ac- 

 count of its greater activity, that is, the ftrength of the effects 

 which it produces by being brought into conta£l with almoft 

 all moift conduftors, as I have already obfer\'ed, is to be 

 preferred to filver, and in a certain decree to all other metals. 

 The experuiicat i iiave already defcribed with a tin bafon 

 filled with an a^caline fluid, and held in the hands moiftened 

 with water, by which an acid fenfation is excited on the 

 tongue when brought into conta6l with the above fluid, is 

 a proof of it j for it would be vain to expeft a like effeft 

 from a bafon of lead, iron, or copper, and much more fo 

 from one of filver. With the latter it would be obtained 

 only when it contained liquid liver of fulphurj and in that 

 cafe the acid tafte would be pretty ftrong. 



The eleftric fluid is excited alfo vi'ith the greateft ftrength 

 and aftivity, when the metal is tin, between water and a faline 

 fluid : but it will be excited with ftill greater energy to pro- 

 duce an acid fenfation on the tongue when the tin is between 

 water and an infipid mucilaginous fluid ; or when the expe- 

 riment is made with a tin bafon filled with a folution of gum, 

 liquid glue, white of an egg, &c. The other metals, in like 

 circumftances, produce fome effeft, but much weaker: filver 

 produces the wcakeft, except with liver of fulphur, as I have 

 already obferved. 



A like experiment, which I made three years ago, and 



exhibited to various perfons, not with two different fluids 



and one metal, as in that above defcribed, bul contrariwife, 



5 with 



