

LIVING TOEPEDOS IN BERLIN. 503 



yielding the result sought for. At first, I charged the jar as 

 strongly as possible, with fifty revolutions of the disk, and the 

 polarisations produced by the discharge absolutely and relatively 

 positive by the homodromous, absolutely positive and relatively 

 negative by the heterodromous shock attained an indescribable 

 intensity: many minutes passed before the end of the scale 

 appeared again in the field of view. Then I decreased the number 

 to five revolutions, to two, and even to one, yet still the com- 

 paratively weak shocks were followed by polarisations of great 

 strength and perfect uniformity. For example, I obtained with 

 five revolutions, 



t + 270 4 - 470 f + 125 | - 250. 



Nothing whatever was to be seen of heterodromons relatively 

 positive polarisation. 



It is unnecessary to state, that all measures were taken to 

 exclude direct actions of the shocks of the jar on the galvanometer, 

 and that a clay model in the place of the preparation, showed at 

 most the very faintest trace of negative polarisation. 



I did not proceed further on this path, and I do not believe that 

 any other result is to be attained here. But ( 15) in a later 

 experiment, which unfortunately only succeeded once, the hetero- 

 dromous current actually produced relatively positive, absolutely 

 negative polarisation. 



7. The apparent irreciproeity of the conduction in the 

 electrical organ increases with the current density. 



In the first communication, I closed the examination of the 

 nature of the homodromous, absolutely and relatively positive 

 polarisation with the words, ' There is still one method of ex- 

 periment at hand, which under certain conditions might lead 

 to the attainment of the object, that is to observe whether with 

 a longer closing time, the homodromous current maintains its 

 preponderance. If this is the case, positive polarisation cannot 

 be identified with the shock ; for the latter, when the current goes 

 for a long time through the organ, can only add itself to the 

 battery current at the moment of closing. I have in fact seen this 

 ascendancy with a closing time of i", 5", or even 20", but ex- 

 periments of this kind will not be conclusive until the hypothesis 

 of an irreciprocal resistance can be completely set aside.' 



It is beyond question, that even with a much longer period of 



