EFFECTS OF ELECTRICAL WAVES 485 



with the spinal cord. If the nerves are laid parallel to the 

 spark discharge maximal effects are obtained when the 

 muscle preparations lie in a symmetrical position with rela- 

 tion to the two spheres of the discharger (Fig. 138), while 

 every displacement of the preparation toward one side (Fig. 

 139) diminishes the effects or causes them to cease entirely. 



o o 



FIG. 139 



If, on the other hand, the nerves of the muscle preparations 

 are laid at a right angle to the spark discharge, minimal 

 effects are obtained when the preparation lies in a position 

 symmetrical with the two spheres of the discharger (Fig. 

 140), while maximal effects are obtained when the muscle prep- 

 arations are moved laterally a sufficient distance (Fig. 141). 



-e a 



A 



t 



V 



FIG. 140 



The explanation which I gave of these phenomena was 

 as follows: 



a) Let it be assumed that the two muscle preparations 

 lie parallel to the spark discharge and in a position sym- 

 metrical with reference to the discharger (Fig. 138). If at 

 a certain time the one sphere of the discharger is charged 

 positively, the other negatively, a corresponding distri- 

 bution of the electricities is induced in the nerve-muscle 



