p^olta on Aidmal EhBricify. 6y 



Hn alkaline liquid, belongs, as you may perceive, to this fe- 

 bond method of exciting the eleclric fluid and putting it in 

 circulation (if the tin veliel be touched on the outfide by the 

 hand moiftened with water, and on the infide by the alka- 

 line liquor), and (liews that this current is no lefs ftrong and 

 aftive than that excited bjf the firft method, viz. by employ- 

 ino- two fufliciently well chofcn metals, fuch as lead and 

 coppprj iron and filver, zinc and tin. I muft here qbfcrve, 

 that though with tin alone, placed between water and an 

 alkaline liquor, you obtain nearly the effeSt which is produced 

 by two of the moft diftcrcnt metals, as filver and zinc, com- 

 bined with any conductor whatever of the fecond clafs ; you 

 can obtain the fame, and even in a higher degree, w^ith iron 

 alone or filver alone, when the iron is Introduced between 

 water on the one fide and nitrous acid on the other, or 

 when the filver is applied between water and a folution of 

 fulphure of pot-afli. 



If you take a frog, the head of which has been cut off, 

 and which has been deprived of all life by thrufting a needle 

 into the fpinal marrow, and immerfe it, without (kinhing it, 

 taking out the bowels, or any other preparation, into two 

 glafles of water, the rump into one, and the leg into the 

 other as ufual, it will be flrongly agitated arid violently coti- 

 vulfed when you conneft the water in both glafles by a bow 

 formed of tw'O very different metals, fuch as filver and tin or 

 lead, or, what is better, filver and zinc ; but this will by no 

 nicaris be the cafe when the two metals are lefs ditterent in 

 regard to their powers, fuch as gold and filver, filver and 

 copper, copper and iron, tin and lead. But what is more, 

 the effcdl will be fully produced on this fo little prepared frog 

 when you immerfe in one of the two glafles the fend of a 

 bow merely of tin or zinc, nnd into the other glafs the 

 other end of* this bow which has been rubbed over with a 

 little alkali. You may perform thfi experiment ftill better 

 with an iron bow, one end of which has been covered with a 



F z drop 



