MUSCLES, NERVES, AND ELECTRICAL ORGANS. 217 



is stronger in the direction of the shock, while in the organ of 

 the Malapterurus positive polarisation is the stronger. The 

 difference as regards the relation between the nerve-ending and the 

 direction of the shock in the two fishes might be referred to in ex- 

 planation 1 . But in my work on Gymnotus 2 I explained the reasons 

 why I did not consider Dr. Sachs' proof sufficient for his statement. 

 Dr. Sachs had evidently no idea of the complete opposition to me 

 into which he fell, and he contented himself with a single series of 

 experiments on this difficult subject, during which he did not 

 once observe the primary current and therefore w T as satisfied without 

 guarding against irreciprocity of conduction. Under these circum- 

 stances, I must consider the question to be still an open one, which 

 polarisation is the strongest in the organ of the Gymnotus in the 

 direction of the shock ; whether the positive, as in the organ of the 

 Malapterurus, or the negative, as Dr. Sachs asserts. 



Nothing is known as yet about the polarisability of the organ of 

 the Torpedo, except that I discovered an experiment of Configliachi's 

 of the year 1805 in which it appears that several organs of Torpedos 

 laid upon each other were charged like a Hitter's secondary battery 3 , 

 i. e. were polarised negatively. 



It is unnecessary to say that in the secondary electromotive actions 

 of the electrical organs we have to do with the sum of the actions of, 

 the individual electrical plates. The view might be taken that on 

 polarising the organ only the electrical nerves of the organ were 

 the seat of polarisation. In the Malapterurus, however, the mass of 

 these nerves is so small in proportion to that of the electrical 

 structures, that this idea appears to be quite untenable. 



I have already repeatedly treated of the teleology of the polarisa- 

 tion of the electrical organ that is to say, of the part it possibly 

 plays in the mechanism of the shock 4 . 



21. Theoretical. Closing Remarks. 



The sum of the observations I have communicated, proves that 

 muscles, nerves, and electrical organs are polarisable according to a 

 common law, up to this time only observed in themselves. In ad- 

 dition to internal negative polarisation, which though at first sight 

 indistinguishable from that of other moist porous bodies, yet is 



1 Cf. Gesammelte Abhandlungen, vol. ii. p. 618. 

 3 Loc. cit. pp. 218, 219. 



3 Gesammelte Abhandlungen, vol. ii. p. 719, Anm. 



4 Gesammelte Abhandlungen, p. 722 ; Untersuchungen am Zitteraal, p. 220. 



