520 LIVING TORPEDOS IN BERLIN. 



11. Dependence of the irreciprocal resistance and of the resist- 

 ance of the organ in general upon its vital condition. 



The small conducting- power of the organ and its irreciprocity are 

 closely connected with its vitality. If the tube was filled with columns 

 which projected at both ends, and plunged in boiling- water for 

 several minutes, in consequence of which the organ acquired an acid 

 reaction, it remained filled with organ in spite of the shrivelling of 

 the columns by the boiling. I have already stated that boiled 

 organ conducts better than living organ (p. 458). I am now 

 able to add, first that its resistance becomes exactly the same in 

 both directions, secondly that after cooling it sinks below the 

 minimum resistance in the homodromous direction, and is even 

 smaller than that of physiological salt-solution. Compared to this 

 as unity, I found it to be only = 0-9294. 



The course of events is similar when the organ dies a natural 

 death, only it is evident that a longer period is required. Here, 

 also, homodromous and heterodromous resistance approximate to 

 equality, and Lomodromous resistance diminishes. Naturally the 

 dead organ, especially in a more advanced stage of decomposition, 

 is ill-fitted for preparations which have to be drawn into the resist- 

 ance-tube. Preparations taken from such an organ, as I remarked 

 long since (p. 439), have a tendency to assume an hour-glass 

 form between the more compact dorsal and ventral skin which 

 covers their polar surfaces. However, it is possible with some 

 patience to obtain determinations like the following. 



The organ of the seventh Torpedo, kept at a low temperature, had 

 an indistinctly acid reaction fifty-five hours after death. It had 

 already a smell of ammonia, and thus the acid was probably 

 neutralized by the ammonium carbonate arising from the decom- 

 position of urea in the tissues, as might be proved by the reaction 

 being acid only here and there in the muscles. The preparations 

 acted feebly in homodromous direction ; however, this could hardly 

 be the organ current, but rather an electromotive action produced 

 by an acid and an alkaline liquid accidentally coming in contact 

 with each other in the interior of the organ. A first preparation 

 gave 



= 3-23 1 



Thus the irreciprocity amounted to only eight per cent, of the 

 homodromous current strength. But in another preparation, it was 



