Abstract
Dual stimuli were applied on one end of the sartorius muscle of Bufo vulgaris, and the evoked action potentials were led by two pairs of silver electrods coated with silver chloride. The distance between the two pairs of electrods furnished on the muscle was 1 cm. In this way, the conduction of the action potenltal between two leading portions of the muscle during the relative refractory period was observed by cathod ray oscilloscope.
From those experiments, it became clear that the excitatory wave propagated decremen-tally along the refractory muscle, and that the recovery of the muscle fiber from the refrac-toriness was not simultaneous along its full length, but it was the more retarded as the more distal from the stimulated portion.
That is to say, the skeletal muscle becomes heterobolic (Verworn's meaning) during the refractory period.
