Health lectures for the people . will choose for this purpose onewith which you are all familiar,viz., the biceps. This muscle, asyou know, forms the projecting massin front of the joint of the upperarm, where the limb is bent forciblyat the elbow joint. Above it isattached by two separate tendonsor heads (hence its name biceps)to the shoulder-blade ; below it isfixed by a cord-like sinew to theradius or outer of the two bones of the forearm a short distancebelow the elbow. When it contracts, it bends the forearm atthe elbow, like a door upon a hinge; and as the contraction ofa muscle is
Health lectures for the people . will choose for this purpose onewith which you are all familiar,viz., the biceps. This muscle, asyou know, forms the projecting massin front of the joint of the upperarm, where the limb is bent forciblyat the elbow joint. Above it isattached by two separate tendonsor heads (hence its name biceps)to the shoulder-blade ; below it isfixed by a cord-like sinew to theradius or outer of the two bones of the forearm a short distancebelow the elbow. When it contracts, it bends the forearm atthe elbow, like a door upon a hinge; and as the contraction ofa muscle is always accompanied by a corresponding thickening,or increase in breadth, we have a marked prominence producedin front of the arm. For the performance of voluntary motion, something more isrequired than the mere muscles. Each muscle must be broughtunder the influence of the nervous system; therefore entering itwe always find one or more nerves. These nerves connect thevarious muscles with the brain and spinal marrow, and by them. Fig. 17 Forearm extended, Biceps musclerelaxed and at rest. THE HUMAN BODY. 53 the movements of the body are excited and controlled. The in-fluence of the nervous system in this respect is manifested by theeffects produced by intoxication, or by the disastrous results fol-
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectpublich, bookyear1882
