. Animal mechanism: a treatise on terrestrial and aërial locomotion. Animal locomotion; Flight. 114 ANIMAL MECHANISM. served for the investigation of the muscular wave (fig. 7, page 87). If we substitute in this figure an experimental shoe for each of the myographical clips 1 and 2, we shall have the arrangement of the apparatus necessary for the study otfootsteps or impacts of the foot on the ground. Fig. 20 has been furnished by an experiment in walking. Two tracings are given by the intermittent pressure of the feet on the ground. The full line D corresponds with the right foot; the dotted
. Animal mechanism: a treatise on terrestrial and aërial locomotion. Animal locomotion; Flight. 114 ANIMAL MECHANISM. served for the investigation of the muscular wave (fig. 7, page 87). If we substitute in this figure an experimental shoe for each of the myographical clips 1 and 2, we shall have the arrangement of the apparatus necessary for the study otfootsteps or impacts of the foot on the ground. Fig. 20 has been furnished by an experiment in walking. Two tracings are given by the intermittent pressure of the feet on the ground. The full line D corresponds with the right foot; the dotted line with the Fig. 20.—Tracings of the impact and the rise of the two feet in our ordinary walk. Knowing the arrangement of the apparatus, we can under- stand that each impact of the foot on the ground will be represented by the elevated part of the corresponding curve. In fact, the pressure of the foot on the ground compresses the india-rubber sole and diminishes the capacity of the included air-chamber. A part of the contained air escapes by the con- necting tube, and passes into the registering drum. We see in fig. 20 that the pressure of the right foot, for instance, commences at the moment when that of the left begins to decrease; and that in all the tracings there is an alternation between the impacts of the two feet. The period of support of each foot is shown by a horizontal line which joins the minima of two successive curves. The impacts of the right and left feet have the same dura- tion, so that the weight of the body passes alternately from one foot to the other. It would not be the same with respect to a lame person; lameness corresponds essentially with the inequality of the impacts of the two feet. There is always a very short period during which the body is partially supported by one foot, but when it already be- gins to rest on the other; this time is scarcely equal to the. Please note that these images are extracted from scanned page images that may
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectflight, bookyear1874
