PRESENT STATE OF OUGANIC ELECTKICITV. :'i23 



have conceived the contractions to be due to electricity evolved 

 by the metals ; ])ut finally he concluded that it is produced 

 by the animal textures themselves. The researches of Volta 

 verified tlie orii^'inal oi)ini(in of (Jalvani, that tlie metals, when 

 tluil arc cmphnii'd, are tlie sources of the electricity which 

 produce the muscular contractions ;* but the discovery of the 

 pile, with its consequences, threw into temporary oblivion the 

 actual evidences of an electromotor property of the animal 

 textures imh'pcyulently of metal.% which the numerous expe- 

 riments of Galvani and his supporters had affordedf Even 

 Humboldt's observations did not prevent the almost total ne- 

 glect of the subject for a quarter of a century, t 



In 1827, Nobili, || having applied his improved galvanometer 

 to the fundamental experiment of Galvani, discovered the elec- 

 tric current of the frog. He found that when the circuit of 

 the nerve and muscles of the leg is closed by the instrument, 

 a deviation of the needle to the extent of 10°, 20°, or 30°, oc- 

 curs, due to a current which passes in the limb from the toes 

 upwards, and which could be increased by inclosing in the 

 circuit several frogs arranged as a batter}'. There could no 

 longer be any doubt of the truth of Galvani's later opinion, 

 that electricity is developed in connection with muscle and 

 nerve. 



The researches of Matteucci, carried on during a transi- 

 tionary stage of the subject, and exhibiting occasional ob- 

 scurity and contradiction, are, nevertheless, valuable, not only 

 from having directed attention generally to elcctro-physiolog}', 

 but particularly from having, in regard to muscle, indicated 

 that its electric properties are due to its own texture, and not to 

 the conjoined nerves. He had always, however, experimented 



* Nuova Memoria ddV Ehdricita Animalf^ etc. 



+ DelV uao e ddV altivUd ddV arm eondtUtvre nW conirarione dt' mitaeoii, 



1793 ; ami SitpplinifiUo al Tratatto dfW iuk\ t-tc 1794. 



X Vcrswhc uflter dir gfrn'zie j\ftuld-uiut Xervrn/tiscr, ii. s, w. , 1 797. 

 II Ami. df Chiin. rt dt Phys. 182S 



