LIVING TORPEDOS IN BERLIN. 531 



vanish, as compared with the distance of the element of surface 

 under consideration, then the density of the current in the element 

 is doubled by the addition of the second column, trebled by that of 

 the third, and multiplied n times by the addition of the n ih column. 

 As the distance of the element of surface diminishes, the density of 

 the current increases in it more slowly with the addition of new 

 columns and in a very complicated manner, but it constantly 

 increases with the number of columns. As each column represents 

 for all other columns, a portion of external space, each one will 

 be met by a portion of the current threads of the others, for the 

 most part heterodromously, and the components of the external 

 currents are deducted in the interior of the column from those of 

 its own current. This is what I call the principle of imperfect 

 pile formation, and thus it is comprehensible, how without insu- 

 lating coverings, a multiplication of elementary effect is possible in 

 electrical organs. 



Further consideration is simplified by the remark, that since the 

 Torpedo possesses two organs symmetrically placed, it is sufficient 

 to fix the attention on one column symmetrically placed in each 

 organ. The sagittal plane VD of the fish, when extended to 

 infinity, is a surface of flow for the process of flow due to both 

 of these columns. Consequently we can think of it as insulated, 

 without changing anything in the process, or we may also halve 

 the infinite conducting space in this plane, and we require to inves- 

 tigate only what takes place in one half of it. 



It is clear from the above, that all other columns of an organ are 

 traversed heterodromously by the current threads of the one column 

 under consideration, as is shown in Fig. 23 to the left of the sagittal 

 plane. If we fix our attention upon a portion of external space, 

 e.g. the little fish seen in the figure, then the rest of the current 

 threads form a collateral channel of closure for the current threads 

 which meet the little fish. The worse this conducts, so much the 

 stronger is the shock which the fish receives. Consequently, it 

 would receive a stronger shock if the organ were insulated, with 

 the exception of the particular column under consideration. This 

 is represented in the figure, to the right of the sagittal plane, where 

 the shading is intended to signify insulation. Thus, the current 

 threads issuing from the margins of the dorsal surface and the 

 upper half of the lateral surface of the column, can no longer pass 

 through the adjoining columns to the corresponding points below 

 the median transverse plane (which will be almost bent here to a 



M m 1 



