ELECTROCARDIOGRAMS 



275 



A. Normal 



B. Apex cooled 



C. Apex' warmed 



Fig. 84. Records of electrocardiogram and movement of ventricle of frog showing that when 

 the apex is warmed a typical T-wave appears in place of a wave in the opposite direction appear- 

 ing when the apex is cooled. (From Mines.) 



