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A MANUAL OF PHYSIOLOGY 



because a smaller number of fibres are excited (p. 141). The objects 

 used for the study of muscular contraction contain many fibres, and 

 it is not in general possible to distribute the stimulus equally to all. 

 This is true for smooth muscle as well as for striped. Finally, increase 



FIG. 229. PENDULUM MYOGRAPH. 



At the left as seen from the side, at the right as seen from the front. A, bearings 

 on which the pendulum swings ; P, pendulum ; G, G', glass plates carried in 

 the frames T, T' ; a, pin which opens the trigger-key. The key, when closed, 

 is in contact with c, and so completes the circuit of the primary coil. 



of the load per unit of cross-section of the muscle diminishes above a 

 certain limit the ' height of the lift,' although below that limit it may 

 increase it. 



Influences which affect the Time-relations of the Muscular Con- 



