. Animal locomotion or walking, swimming, and flying : with a dissertation on aëronautics. aracter : the right leg and left arm advancingtogether to form one step; the left leg and right arm advanc-ing together to form the next. The diagonal movementsbeget a lateral twisting of the trunk and limbs; the oscilla-tion of the trunk upon the limbs or feet, and the oscillation PROGRESSION ON THE LAND. 59 of the feet and limbs upon the trunk, generate a forwardwave movement, accompanied by a certain amount of verticalundulation. The diagonal movements of the trunk andextremities are accompanied by a
. Animal locomotion or walking, swimming, and flying : with a dissertation on aëronautics. aracter : the right leg and left arm advancingtogether to form one step; the left leg and right arm advanc-ing together to form the next. The diagonal movementsbeget a lateral twisting of the trunk and limbs; the oscilla-tion of the trunk upon the limbs or feet, and the oscillation PROGRESSION ON THE LAND. 59 of the feet and limbs upon the trunk, generate a forwardwave movement, accompanied by a certain amount of verticalundulation. The diagonal movements of the trunk andextremities are accompanied by a certain degree of lateralcurvature; the right leg and left arm, when they advance tomake a step, each describing a curve, the convexity of whichis directed to the right and left respectively. Similar curvesare described by the left leg and right arm in making thesecond or complementary step. When the curves formed bythe right and left legs or the right and left arms are joined,they form waved tracks symmetrically arranged on eitherside of a given line. The curves formed by the legs and. Fig. 27 shows the simultaneous positions of both legs during a step, dividedinto four groups. The first group (^i), 4 to 7, gives the different positionswhich the legs simultaneously assume while both are on the ground ; thesecond group (B), 8 to 11, shows the various positions of both legs at thetime when the posterior leg is elevated from the ground, but behind thesupported one ; the third group (C), 12 to 14, shows the positions whichthe legs assume when the swinging leg overtakes the standing one; andthe fourth group (£»), 1 to 3, the positions during the time when the swing-ing leg is propelled in advance of the resting one. The letters a, b, and cindicate the angles formed by the bones of the right leg when engaged inmaking a step. The letters m, n, and o, the positions assumed by the rightfoot when the trunk is rolling over it. g Shows the rotating forward of thetrunk upon the left foo
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Keywords: ., bookcentury1800, bookdecade1870, booksubje, booksubjectphysiology
