LIVING TORPEDOS IN BERLIN. 443 



For the present we may conclude that the electromotive elements 

 are nearly of equal force in the two fish, and that the difference of 

 potential of the electrical plates increases with their thickness. 

 As regards Matteucci's statement that the force of the organ - 

 current of the whole Torpedo lies between that of a single gas- 

 trocnemius of the frog and that of two such, it is sufficient to say 

 that the electromotive force of the uninjured gastrocnemius is, 

 through parelectronomy either nil or even negative, so that it 

 cannot serve as a unit of measurement. 



The force of the organ-current diminishes as the organ dies ; 

 it possesses, however, great tenacity of life 1 . In fish kept in the 

 cold, an organ-current force of 0-003 ^ *2 Raoult is met with 

 after 24 or even 48 hours. The persistence of the organ-current 

 is a sign of the maintenance of functional activity. Later than 

 this the preparations are not only inactive but occasionally the 

 action is reversed, an observation already made by Zantedeschi as 

 regards the whole fish 2 . Sachs made the same observation on 

 Gymnotus though under somewhat suspicious circumstances 3 . 

 One might seek to explain this reversed action after the cessation 

 of the organ-current, by slight irregularities of a different kind, 

 which according to their direction sometimes assume the sem- 

 blance of remnants of normal organ-current, sometimes of a 

 reversed organ-current. But this reversal. of the current seems to 

 occur too regularly to be so explained, and it recalls too distinctly 

 the similar phenomenon which takes place, also with great regu- 

 larity, in certain more delicate muscles as they gradually die 4 . 



The same diminution and irregularity in the force of the organ- 

 current which is observed in the dying organ of Torpedo, appears to 

 occur in the living fish under unfavourable circumstances as regards 

 nourishment. For when I repeated the experiments in winter on 

 a Torpedo 29 cm. in length which had been about seven weeks 

 in the Aquarium and was killed as before by punching the 

 electrical convolutions, I did not obtain the same effects, but only 

 deflections indefinite in direction and extent, which might have 

 been dependent on slight differences in the skin or on other 

 disturbances. Even the bundles of columns from this fish were 

 either inactive or showed reversed action, though one of them 



1 Berichte, 1882, vol. i. p. 500. Compare Untersuchungen, p. 188. 



2 Comptes rendus, 1842, vol. xiv. p. 489. 



3 Untersuchungen, p. 258. 



* Ibid. vol. ii. pt. i. pp. 154, 283, 553. 



