CII. IX. 



COMPOSITION OF TETANUS 



103 



. 124. Composition of tetanus. These six tracings were obtained on a slowly moving drum from a 

 frog's gastrocnemius, which was excited by a succession of induction shocks. By a mechanical 

 contrivance the rate of the vibrating hammer which interrupted the primary circuit of the 

 inductorium could be easily varied ; and the rate of the hammer was increased from about 1 per 

 second in A to 30 per second in F. In A, separate twitches are seen; in B, the rate was still 

 insufficient to cause fusion ; in both A and B, the staircase effect is well seen. In C and D, the 

 rate was sufficiently great to cause incomplete tetanus; in E, tetanus was nearly complete, and 

 in F it is complete. The time-tracing in each case shows half-seconds. 



