£00 HISTORY OF GALVASlS^f. 



either imme- the nerve alone, Fowler dill confiders it rcquifite that fliers 



^mediately by ^ a conne ^'°n between the nerve and (he mufcle ; in orcli- 



water. nary cafes this connection is effected by the moidure which 



adheres to the nerve, a circumfhmce which Volta feems to 



have overlooked. Valli had endeavoured to form a theory of 



animal electricity founded upon the idea that the eleclric fluid 



was unequally difperfed through the body, and that the appli- 



Attcmpttodif- cation of the metals produced an equilibrium; Fowler per- 



prove the theory f orm ed a number of experiments to difprove this idea, and 



of an electric . i ' l , * ■ " h 



charge in the apparently with luccels. He concludes the tint part of his 

 *nima! iyftcm j efFay by giving it as his opinion, that the phenomena of galva- 

 and to fjicw that -r , -i Cl * 1 1 i f 1 \o • 5- 



garfyanifm is not mmi are not reconcileable to the known laws or electricity, 



electricity, becaufe for the excitement of the eleclric fluid, motion between 

 an eleclric and a condu6tor appears to be neceflary, whereas 

 in thefe experiments two metals only are the fubi!ance& em- 

 ployed. He alfo failed in caufing charcoal to conducl this 

 influence, though it is a better conductor of eieclricity than 

 the animal fluids ; in this particular, however, he appears to 



Torpedo-. have been miltaken. Pie confiders the influence as very dmi- 



lar in its effecls to the action of the torpedo* though not alto- 



EfFecl on worms, gether the fame. He was unable to produce the mufcular 



and on the m- con traclions in worms, yet he found that when a worm or a 



voluntary mui- J , 



clcs. leech lying uponfllver, put its mouth upon zinc, it appeared 



to differ great uneafinefs. Dr. Fowler in the fecond place 

 proceeds to enquire, whether all the mufcles of the body be 

 iubjeel to this new influence. He found it difficult to excite 

 any contraclions in the heart, though at length, by ufing pro- 

 per precautions, he fucceeded ; but he was not able to excite 

 Difcovery of the contraclions in the domach or intedines. He difcovered that 

 flain » W b when the nerves of vifion were acled upon by the two metals, 

 a fenfation of a flalh of light was perceived in the eye. When 

 inflammation was excited in a limb, it appeared to acquire 

 additional fenfibility to the galvanic influence. Fowler's work 

 Profefibr Robi- concludes with a letter from Profeffor Robifon, who made 



ion makes a f om e new obfervations upon the produclion of the galvanic 



pile of zinc and . 



iilver. flafh, and fird noticed the effect produced by applying the 



tongue to a number of pieces of diver and zinc alternately 



piled upon each other. 

 Darwin in 1794 In 1794- the fird volume of the Zoonomia was publiflied ; 

 confiders galva- j} arwm fpeaks of the phenomena of galvanifm, and confiders 

 eity. them as eleclrical. The mufcular contraclions he fuppofes 



depend 



