34 THE PHYSIOLOGY OF MUSCLE AND NERVE. 



of value. When the contraction appears late in the series of contractions 

 it is usually permanent, that is to say, it wears off only as the muscle relaxes 

 slowly from fatigue. Toward the end of such a series the muscle is often 

 practically in a state of continuous contraction, a condition which would 

 nullify its ordinary use in locomotion. It seems possible that certain con- 

 ditions of tonic spasm or cramps which occur during life may involve this 

 process, for example, the temporary cramp that sometimes attacks a player 



Fig. 15. Effect of repeated stimulation; complete curve, showing late contracture. 

 The muscle was stimulated by induction shocks at the rate of 50 per minute. The separate 

 contractions are so close together that they can not be distinguished. 



Fig. 16. Effect of repeated stimulation, curve showing no contracture or very little. 

 The muscle was stimulated by induction shocks at the rate of 50 per minute. A very 

 slight contracture is shown in the beginning, but subsequently the contractions show 

 .nly a diminished extent, the rate of relaxation remaining apparently unchanged. 



in athletic games, or the curious spasmodic condition known as intermittent 

 claudication, in which the muscles on exercise are thrown into a state of 

 tonic contraction. From the physiological standpoint the phenomenon of 

 contracture when compared with that of the simple contraction indicates the 

 possibility that two different contraction processes may take place in muscle, 

 one involving the state of tone and, therefore, the length and hardness of 

 the muscle, the other controlling the movements proper. This suggestion 



