. General physiology; an outline of the science of life. 462 GENERAL PHYSIOLOGY frequently in the cross-striated skeletal muscles of vertebrates. Since by means of the graphic method muscular movement can be recorded and its individual factors made visible, the progressive fatigue of the muscle can be studied very conveniently in the change undergone by the curve that the contracting muscle records. Mosso ('91) has done this in the living man by means of his ergograph, and has presented the results in his excellent and fascinating book entitled " La ; The ergograph is a small
. General physiology; an outline of the science of life. 462 GENERAL PHYSIOLOGY frequently in the cross-striated skeletal muscles of vertebrates. Since by means of the graphic method muscular movement can be recorded and its individual factors made visible, the progressive fatigue of the muscle can be studied very conveniently in the change undergone by the curve that the contracting muscle records. Mosso ('91) has done this in the living man by means of his ergograph, and has presented the results in his excellent and fascinating book entitled " La ; The ergograph is a small apparatus in which the arm of a man is fastened by means of a holder, while one finger is free to move. This finger is connected by a cord with a writing-lever, which records upon a rotating drum all the movements of the finger that take place, either voluntarily or. Fig. 236.—Mosso's-ergograph. (After Mosso.) invohmtarily as the result of electrical stimulation. A weight can be hung upon the cord, and thus the work performed by the flexor muscles of the finger can be changed at will (Fig. 236). By means of this apparatus it can be shown very clearly that, with the stimulating induction-shocks remaining constant in intensity and following each other at equal intervals, the work performed by the muscles constantly decreases, and finally becomes equal to zero. This is expressed in the curve of contraction, which gives only the extent of the contraction, by a constant decrease in the height of the lift (Fig. 237). After a course of contractions it requires considerably stronger stimulation to produce further con- traction of the fatigued muscles equal in height to that at the beginning. The details of the changes are more readily visible when the successive contraction-curves of a frog's leg are ^jecorded i>ver one another upon a myograph from the beginning of the. Please note that these images are extracted from scanned page images that may have been digitally enhanced for r
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