426 LIVING TORPEDOS IN BERLIN. 



consists only in a more rapid loss of power by the Torpedos ; and in 

 fact Matteucci and Boll report that ' the energy of the electrical 

 organs is rapidly diminished in captivity 1 .' 



The uncertainty whether in individual experiments the fish had 

 been excited or not, made it most desirable to be assured on this 

 point by means of the frog-alarum. Fig. 13 shows how I usually 

 connected it with the fish. The diagram is easily understood the 

 Gastrocnemius G, the bell T, the hammer //, the weight E. The 

 electrode v'" (not represented in the figure) of the exciting tubes 

 was connected by the wire v"i/ with the ventral shield. The 

 other electrode d m was connected by the wires d"\ d" with a 

 circular zinc plate 3 cm. in diameter which extended horizontally 

 from the edge of the basin under the sea water ; it served for the 

 frog-alarum the purpose of the dorsal shield. In experiments in 

 which no ventral shield was used the ring electrode v'" was con- 

 nected with a similar zinc plate v' (shown in the figure by a dotted 

 line) on the floor of the basin. The frog-alarum did not seem to 

 be so reliable as in the experiments on Malapterurus, a result 

 which was partly due to the greater conductivity of sea water 

 than of fresh. Moreover it frequently happened that Torpedos 

 received in spring were more excitable, and, like the Melapterurus 2 , 

 according to the evidence of the frog-alarum, from unknown causes 

 gave shocks of themselves. 



6. Effect of Torpedo-shock on Man. 



If the handles are grasped with wet hands, and the fish is 

 effectually excited, a shock is felt which only affects the wrist, 

 for reasons already set forth 3 , but which gives a better idea of the 

 phenomenon than any method of seizing the fish directly which can 

 be devised. By this means I communicated the shock to a number 

 of students at my lectures who joined their wet hands together. 

 The weakness of the Torpedo-shock as compared with that of 

 Malapterurus (still vividly present to my mind) was veiy striking. 

 As, however, in my method of receiving the first shocks, the 

 strength of the Torpedo-shocks is necessarily much diminished from 

 the absence of insulation and the good conductivity of sea water, 

 I cannot regard this observation as a confirmation of Babuchin's 

 statement that the strength of the shock of Malapterurus exceeds 



1 Archiv fur Anatomic, 1873, p. 78. Professor Fritsch complains of the sluggish- 

 ness of Torpedos in winter, even when freshly caught in the Mediterranean. Sitz- 

 ungsberichte, 1882, vol. i. p. 500. 



2 Gesammelte Abhandlungen, vol. ii. p. 408. 3 Ibid. vol. ii. p. 619. 



