PHENOMENA OF MUSCLE AND NERVE. 301 



There is then abundance of proof of the fact overlooked by du 

 Bois-Reymond that the + phase of the after-current in muscle prevails 

 only in the region of the anode. 



In the case of nerve the experiments which have been pre- 

 viously cited showed that there was no difference of behaviour 

 whether the leading-off occurred close to the anode or close to the 

 kathode. This should not surprise us since, in nerve, anelectro- 

 tonus extends with strong 1 currents quite up to the kathode. In 

 spite of this it seemed desirable to employ upon nerves, the methods 

 used in the case of muscle in order to obtain more decided differ- 

 ences between the behaviour of nerve at the anode and kathode : in 

 point of fact such differences were obtained. 



For this purpose a polarising and a leading-off electrode were 

 laid upon a destroyed spot in a nerve. The middle portion of a 

 nerve preparation, made as before described by laying- two nerves 

 together, was destroyed by dipping it into hot water (the prepara- 

 tion being first folded in the middle so that the two halves lay side 

 by side). As however the vapour severely injures the remaining 

 portions of the preparation, as described by me in an earlier work ; 

 this method was abandoned 1 , and in the later experiments the 

 piece of nerve-preparation was effectually squeezed between the 

 blades of a small vice. Still, the first method of treatment gave 

 results invariably like the second. 



It appeared that in nerve also, with appropriate strength of 

 current, the + phase of the after-current regularly failed when the 

 physiological anode and one leading-off electrode lay on the artificial 

 cross-section. 



Example. Two sciatic nerves placed side by side in opposite 

 directions; and squeezed in the middle for 9 mm. (the squeezed 

 part is indicated in the schema by the dark line). Polarising- 

 current led in at AB. 



c" 



case (due to particular distance as well as length of coil), the highest attainable 

 delicacy being taken as unit. The distances were so arranged that this ratio should 

 be as nearly as possible a round number. With my galvanometer, the bobbin of 

 which is immovable, another extra bobbin was used. See Pflviger's 'Archiv,' vol. 

 xxiv. p. 254. 



1 Loc. cit. vol. xxiv. p. 354. 



