398 



A MANUAL OF VETERINARY PHYSIOLOGY 



The effect of veratrine poisoning, on muscular contraction, is 

 very remarkable ; apart from the fact that the curve sometimes 



Fig. 1 1 6. — Fatigue^Curve of^Skeletal Muscle; Gastrocnemius of 

 Frog (Stewart). 



Time -tracing T ^ ¥ of a second. The curve is read from right to left. 



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Fig. 117. — Veratrine Curve compared with Normal : Frog's Gastroc- 

 nemius (Stewart). 



The tuning-fork marks hundredths of a second. Between 1 and 2 a portion of 

 the time-tracing corresponding to one and a half seconds has been cut out, and 

 between 2 and 3 a portion corresponding to one second. The Veratrine curve 

 does not show a peak. At 3 it has not yet fallen to the base-line. 



shows a second contraction, there is a prolonged period of 

 retarded relaxation or maintained contraction (see Fig. 117)* 



