ELEMENTARY EXPERIMENTAL PHYSIOLOGY 



41 



FIG. 46. Effect of two successive maximal stimuli, with gradually diminishing 

 intervals, upon the gastrocnemius. To be read from below upwards. 



H. Time tracing, 50 per sec. In the two upper curves are shoVn both the con- 

 traction in response to the first stimulus alone and the combined contractions caused 

 by the two successive stimuli. (M.S. P.) 



A. Time tracing, 100 per sec. Recorded on a drum revolving at a much faster rate. 

 The second stimulus was sent in well within the latent period of the first. (A.P.B.) 



