. Animal locomotion or walking, swimming, and flying : with a dissertation on aëronautics. sing the icing, and in preparing it for the stroke fromleft to right, and vice versa; a continuous to-and-fro move-ment devoid of dead points being thus established. If theartificial wave wing be taken in the hand and suddenly de-pressed in a more or less vertical direction, it immediatelysprings up again, and carries the hand with it. It, in fact,describes a curve whose convexity is directed downwards, andin doing so, carries the hand upwards and forwards. If asecond down stroke be added, a second carve
. Animal locomotion or walking, swimming, and flying : with a dissertation on aëronautics. sing the icing, and in preparing it for the stroke fromleft to right, and vice versa; a continuous to-and-fro move-ment devoid of dead points being thus established. If theartificial wave wing be taken in the hand and suddenly de-pressed in a more or less vertical direction, it immediatelysprings up again, and carries the hand with it. It, in fact,describes a curve whose convexity is directed downwards, andin doing so, carries the hand upwards and forwards. If asecond down stroke be added, a second carve is formed ; thecurves running into each other, and producing a progressivewaved track similar to what is represented at a, c, e, g, i, offig. 81, p. 157. This result is favoured if the operator runsforward so as not to impede or limit the action of the wing. How the Wave Wing creates currents, and rises upon them,and how the Air assists in elevating the Wing.—In order toascertain in what way the air contributes to the elevationof the wing, I made a series of experiments with natural. Fig. 1-29. and artificial wings. These experiments led me to concludethat when the wing descends, as in the bat and bird, itcompresses and pushes before it, in a downward and forward 254 AERONAUTICS. direction, a column of air represented by a, b, c of fig. 129, The air rushes in from all sides to replace the dis-placed air, as shown at d,e,f,g,h,i, and so produces a circleof motion indicated by the dotted line s, t, v, w. The wingrises upon the outside of the circle referred to, as more par-ticularly seen at d, e, v, vj. The arrows, it will be observed,are all pointing upwards, and as these arrows indicate thedirection of the reflex or back current, it is not difficultto comprehend how the air comes indirectly to assist inelevating the wing. A similar current is produced to theright of the figure, as indicated by /, m, o, p, q, r, but seeingthe wing is always advancing, this need not
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