. The elements of physiological physics: an outline of the elementary facts, principles, and methods of physics; and their applications in physiology. Biophysics. 126 PHYSIOLOGICAL PHYSICS. [Chap. sator. being properly arranged in circuit, as shown (Fig. 65), the disc of the instrument is turned so that the platinum wheel rests on the zero point of the wire. The current from the muscle is then allowed to go through the galvanometer, and a deflection results. The disc is then slowly turned, so that the zero point is carried away from the wheel. This permits the Daniell current access to th
. The elements of physiological physics: an outline of the elementary facts, principles, and methods of physics; and their applications in physiology. Biophysics. 126 PHYSIOLOGICAL PHYSICS. [Chap. sator. being properly arranged in circuit, as shown (Fig. 65), the disc of the instrument is turned so that the platinum wheel rests on the zero point of the wire. The current from the muscle is then allowed to go through the galvanometer, and a deflection results. The disc is then slowly turned, so that the zero point is carried away from the wheel. This permits the Daniell current access to the galvanometer, and the needle slowly returns as the disc moves. "When the needle is again at zero of the scale, the disc is allowed to remain where it is, and then the new position of the platinum wheel r is read off. The distance now between zero of the wire and r is proportional to the strength of the branch current from the Daniell, sent through the galvanometer to compensate for the muscle current. Effect of electrotomis on electromotive force.—With the aid of the galvanometer, then, it has been found that muscles and nerves give rise to an electric current, that is, develop electromotive force. It has been mentioned towards the close of chapter viii., that the passage of a constant current of electricity through a nerve alters its electromotive force, but, because it involves the use of the galvano- meter, it was left to this chapter to show how this is proved. The arrangement is precisely that already described ; a long nerve is, however, required. Let the zinc troughs be placed in connection with the galvano- meter, a key being interposed, and let the nerve be placed with the transverse section of one end on one clay pad, and let a part of the longitudinal surface near that end touch the clay of the other trough. This leaves the other end of the nerve free to be laid. Please note that these images are extracted from scanned page images that may have been digitall
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Keywords: ., bookcentury1800, bookdecade1880, bookpublisherphila, bookyear1884
