248 RESEARCHES ON SECONDARY ELECTROMOTIVE 



which was in contact with one stimulating 1 electrode, first the point 

 of entry, then the point of exit of the stimulating- current. Through 

 the kathodic action of the current the susceptibility of the muscle 

 for positive anodic polarisation was soon diminished in the neigh- 

 bourhood of both the stimulating electrodes, so that the preponder- 

 ance of negative kathodic polarisation kept increasing, and at the 

 same time there was negative polarisation even at the anode. 



As the whole intrapolar tract was included in the galvanometer 

 circuit, only the algebraic sum of the anodic and kathodic polari- 

 sation-current would find expression in the deflection of the magnet. 

 I adopted substantially Tschiriew's method in my earliest experi- 

 ments on polarisation of muscle. I applied to the under surface of 

 the horizontally extended muscle, across its long axis, two small 

 cylinders of the clay used for electrodes, these cylinders being in 

 contact on one side with the stimulating electrodes, on the other with 

 the galvanometer electrodes. This arrangement has the advantage 

 over that of Tschiriew, that the polarising currents enter and leave 

 the muscle at the same points as the galvanometer-currents. In 

 comparison with du Bois-Reymond's arrangement, Tschiriew's 

 has the advantage that the polarisation currents recorded were 

 always the result of two polarisations, one anodic, the other ka- 

 thodic, whilst in du Bois-Reymond's experiments, besides the two 

 polarisations in the neighbourhood of the stimulating electrodes, the 

 considerable polarisations at the tendinous intersections come into 

 account. 



I also made some experiments with du Bois-Reymond's muscle 

 preparation, as well as with the muscle which he calls gracilis, 

 by itself, introducing the current through the bones. With this 

 arrangement from one and the same muscle, with the same intensity 

 and strength of current, I obtained polarisation currents which 

 were of different strengths and differently directed, according 

 as I applied the electrodes to one or another spot of the muscle, 

 keeping the electrodes in all cases about I cm. apart. This was 

 the case whether I used the same pair of electrodes, and shifted 

 them before each new stimulation, or whether I used several pairs 

 of electrodes, and connected them alternately with the galvanometer, 

 as described above for analogous experiments. The confusion of 

 differently directed or diphasic polarisations was so great that I did 

 not feel tempted to pursue the matter further. If the electrodes are 

 always applied in the same position to the muscle, the polarisation 

 currents must necessarily follow a certain law. 



