360 Analogy between this [Book DC, 



moifture, &c. Dr. Valli informs us, that he obferved 

 the hairs of a moufe, attached to the nerves of frogs 

 by the tin-foil with which he furrounded them, alter-* 

 nately attracted and repelled by each other, whenever 

 another metal was fo applied as to excite contractions 

 in the frogs. 



Like the electric fluid, it excites a fenfation of 

 pungency in the tongue ; and paffes with fimilar 

 rapidity through the bodies of animals. 



It differs from the electric fluid in many refpects. 



In order to excite the electric power, it is neccffary 

 that there fhould be motion or friction between two 

 fubftances, an electric and a conductor. Animal 

 electricity is produced by two metals, which are both 

 conductors and without friction. 



According to Dr. Fowler, charcoal is a better con- 

 ductor of electricity than the fluids of animal bodies. 

 Whereas he never could make the influence in queftion 

 pafs through charcoal. 



Dr. Fowler in oppofition to Dr. Valli alledges, that 

 he could not obferve that the niceft electrometers were 

 affected by this influence. 



The fame author remarks, that the moft important 

 and characteriftical difference which he has yet been 

 able to djfcover between this new influence and electri- 

 city, confifts in their effects upon the contractile power 

 of animals and of plants. The contractions of animals 

 excited by electricity, have a tendency to deftroy that 

 power upon which contractions depend. But the 

 contractions excited by the application of the metals, 

 have in all his experiments had the directly oppofite 

 effect. The rrore frequently contractions have been 

 in this way excited, the longer they continue excit- 

 able ; and the longer are the parts upon which fuch 

 experiments are made, preferycd from putridity. 



It 



