ELECTROMOTIVE ACTION IX MUSCLE 



323 



the leading-off circuit. There is practically no current in the 

 circuit uniting symmetrical points. 



If the potential at each point of a longitudinal section is 

 expressed by an ordinate, falling upon the longitudinal section as 



FIG. 102. 



abscissa, the line which unites the summits of the ordinates will, 

 in consequence of the rapid decline of potential towards the 

 end -surfaces, be a curved line with a sharp drop at either 

 extremity. A similar effect is produced at the cross -section 

 (Fig. 103). 



If the regular muscle cylinder is shortened by making new 

 sections, cylinders (prisms) will result, which follow the same law 

 of the muscle current ; the muscle can further be split up longi- 



FIG. 103. Distribution of potential in straight muscle cylinder. (Rosentlial.) 



tuclinally, parallel with the fibres, so that, as du Bois expresses it, 

 an artificial longitudinal section is formed which, like the natural 

 surface, is positive to the transverse section. And no doubt if it 

 were possible to investigate a single primitive fibre in itself, the 

 same opposition would still obtain between longitudinal section 



