342 PKESENT STATE OF OKGANIC ELECTRICITY. 



rated from the nerve, it remains to be determined wlicther 

 an appreciable electric discharge cannot be procured from an 

 isolated element of the battery. If so, it may be presumed 

 that the force which in the form of a contraction is elicited 

 from a muscular fibre by the influence of a motor nerve is re- 

 placed by electric force when the same kind of nerve influences 

 an ultimate element of the electric structure. The laws of the 

 electromotor power of the electric organ cannot be determined 

 by experiments on its entire mass, or on rudely-separated 

 portions of it. The parts must be selected and removed on 

 precise anatomical and physiological principles ; and as Du 

 Bois Eeymond has stated his intention of investigating the 

 electrical organs of the fish, his previous researches show that 

 he will be guided in his proceedings by such considerations. 



If the battery is separated from its nervous centre by 

 section of the trunks of all the nerves which supply it, it will 

 still afford discharges if the nerves are irritated ; and the 

 different portions of the organ, even the smallest, will do so 

 likewise if the nerves which are distributed to them be simi- 

 larly treated. Matteucci, who has latterly admitted that the 

 nervous centre is not the source of the electricity in the fish, 

 states that if even a minute fragment of the battery of the 

 Torpedo is irritated by a spiculum of glass, it will yield a dis- 

 charge.""' 



Peculiar Character of the Electricity evolved from the Bat- 

 teries of the Fish. — The nature of the force evolved from the 

 batteries of the fish is evinced by the shock and spark, by its 

 influence on the galvanometer, its magnetising and heating 

 powers, and its chemical action. The absolute quantity of 

 electricity which the animal can put in circulation at each 

 effort is enormous. For, as it can decompose water, and form 

 magnets, it must greatly exceed the quantity which can be 

 produced by any ordinary electrical machine. It is probable, 



* Traite des Phenomeiies Electro -physiologiques, etc. 



