160 STUDIES IN ELECTRO-PHYSIOLOGY : 



the persona! equation has been allowed for, but when 

 currents of high tension are employed this may be dis- 

 regarded and the data viewed from a different standpoint. 

 For example, an illustration of the muscle-curve produced 

 by the application of a single induction-shock to a muscle, 

 as given in Landois and Stirling, is full of interest, although 

 it does not seem to have conveyed its lesson. 

 Let us see if we can learn anything from it. 



a 



Fig. 84. 



a/, abscissa ; ac, ordinate ; db, period of latent stimulation ; bd, 

 period of increasing energy ; de, period of decreasing energy ; ef, elastic 

 after- vibrations. 



Such is the brief explanation of the curve, but it is, 

 needless to say, elaborated in the text. Any electrician 

 acquainted with submarine cable telegraphy would, 

 however, have in mind what is termed inductive embarrass- 

 ment, and point out the well-known fact that each signal 

 at a receiving station (and muscle is a receiving station) 

 takes a longer time to leave the line than it did to enter it. 

 A momentary signal at starting, it becomes a prolonged 

 signal at its destination, and, furthermore, while a con- 

 denser may be partially discharged, as shown by the curve 

 de, almost instantaneously, it would continue to discharge 

 along the curve ef. All this, I contend, goes to show that 

 the nerve impulse is neuro-electrical, and that muscular 

 contraction occurs through the influence of induction upon 

 condenser-bodies. 



