Electro-physiology (1896-98) Electro-physiology electrophysiolog01bied Year: 1896-98 IV ELECTROMOTIVE ACTION IN MUSCLE 111 cessively sensitive to a brief duration of current (variations of current), it was natural to apply it to the determination of the current of action in muscle. Hermann (45) was the first to experiment with the telephone, but he failed to detect any action current. Bernstein and Schoenlein (46), on the other hand, obtained positive results in 1881 with Siemens' telephone. If 4 to 6 frogs' gastrocnemii were laid in working order upon non- polarisable electrodes (pads), and
Electro-physiology (1896-98) Electro-physiology electrophysiolog01bied Year: 1896-98 IV ELECTROMOTIVE ACTION IN MUSCLE 111 cessively sensitive to a brief duration of current (variations of current), it was natural to apply it to the determination of the current of action in muscle. Hermann (45) was the first to experiment with the telephone, but he failed to detect any action current. Bernstein and Schoenlein (46), on the other hand, obtained positive results in 1881 with Siemens' telephone. If 4 to 6 frogs' gastrocnemii were laid in working order upon non- polarisable electrodes (pads), and their nerves simultaneously excited, a ' crackling sound ' was plainly audible in the telephone, which diminished in clearness with prolonged excitation. Further FIG. 13i5.—Photographic record of action current in Frog's gastrocneinius in strychnia tetanus. (c, c), curves of contraction. (Delsaux.) investigations were carried out on the rabbit. The gastrocnemius muscles were exposed and connected with the telephone by unpolar- isable electrodes, or simple metal needles were pushed through the skin into the muscle, and thence led off to the telephone (Bernstein, 47). In both cases audible tones were obtained, provided the sciatic nerve, which had previously been divided, was tetanised. It was found, on exciting with the acoustic current interrupter, that the number of stimuli might reach 700 per sec., when the note in the telephone, corresponding with the interrupter, was heard with musical integrity. Every note sung into a second telephone (exciting telephone to sciatic) was clearly distinguish-
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