. Directions for laboratory work in physiology for the use of medical students. Physiology. RESPONSE OF HUMAN NKRVKS TO DIRRCT CURRENT. 105 EXPERIMENT XXI. Stimulation of Human Nerves by a Direct Current. Apparatus.—The electric current, which is to be used, is supplied from a dynamo giving 60 volts. Key G, Fig. 24, controls the flow of the current to the rheostat. In the rheostat it is shunted, the current passing through the resistance from P to N, and a portion of it being led off through the metal slider H to the post PP, which gives the branch of current to^ the arm circuit. The resistanc
. Directions for laboratory work in physiology for the use of medical students. Physiology. RESPONSE OF HUMAN NKRVKS TO DIRRCT CURRENT. 105 EXPERIMENT XXI. Stimulation of Human Nerves by a Direct Current. Apparatus.—The electric current, which is to be used, is supplied from a dynamo giving 60 volts. Key G, Fig. 24, controls the flow of the current to the rheostat. In the rheostat it is shunted, the current passing through the resistance from P to N, and a portion of it being led off through the metal slider H to the post PP, which gives the branch of current to^ the arm circuit. The resistance in the rheostat is equivalent to the German silver wire of the rheocord used in Experiment XX. Note that as the slider is moved clockwise^ the resist- ance between the slider and post A^ increases and hence more current mill so to the Fig. 24. Apparatus for stimulation of human nerves by a direct current. G, key; P, post where current enters, and N, where it leaves rheostat; PP, post connected with slider, from which current goes to milammeter; H, slider; I, milammeter; J, commutator for reversing current; K, L,, electrodes; NN, pole on rheostat connected with N and receiving current returning from commutator. In flowing to the arm, the current passes through the milammeter I, and then to the commutator J, through which it is carried to one or the other of the arm electrodes, according to the direction in which the bridge is rocked. If the bridge is rocked towards the electrodes, K becomes the positive electrode, the anode, and L the cathode; if it be rocked away from the electrodes, the current goes through the crossed wires, and I^ becomes the anode and K the cathode. In both cases the current returns from the cathode. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Lombard, Warren P. (Warren Pli
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectphysiology, bookyear1
