492 STUDIES IN GENERAL PHYSIOLOGY 
somewhat closely, we find that in this experiment the nerve 
accidentally lay parallel to the metal plates and somewhat 
outside the area inclosed by the metal plates. This is no 
other experiment than that which I have described under b), 
and which is shown in Fig. 140. In order to convince 
oneself of this fact one 
needs only to turn the 
nerve through an angle 
+ | of 90°, as I have done, 
and lay it parallel to 
A pee Oe the line connecting the 
= oe electrodes (Fig. 145); 
pe one then obtains maxi- 
mal effects when the nerve lies symmetrically with refer- 
ence to the metal plates. We do not deal, therefore, with 
interference in Danilewsky’s experiment, but (as I had 
already shown in my first publication) with the well-known 
fact that the nerve is insensitive, or only slightly sensitive, 
to a current which passes through it transversely. I con- 
vinced myself of the correctness of this interpretation in yet 
another way. One can also obtain minimal effects when the 
nerves lie at right angles to the electrodes and in a dissym- 
metrical position, if the : 
nerves are brought = 
entirely within the area 
between the two metal 
plates as shown in Fig. ae | +e oo 
146. In this way cur- 
rents are obtained which Fits ie 
pass transversely through the nerves. 
The “interference experiments” of Danilewsky are not 
only misinterpreted as far as the purely physiological facts 
are concerned, but their physical analysis leads also to im- 
possibilities. In Danilewsky’s experiment a spark does not 
+t]- |] + 
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