With the technical assistance of 1. Blaiek, M. Rabl and E. Sladkova and the statistical evaluation of Ing. 1. Roth MethodsThe present experiments were performed under pentobarbital anaesthesia (20 to 40 mgAg body \vt iv) on mongrel dogs, weighing from 20 to 25 kg. The electronic device for synchronizing the condenser discharge with selected phases of the electrocardiogram has been described previously. 1 The methods, in general, were also the same as before except that an inductive resistance (inductance 0.29 henry and resistance 27