. Animal flight; a record of observation . ANIMAL Fig. 41. Front view ofpoising kingfisherat beginning ofup-stroke. ment of the up-stroke. Owing to their movement,there must be a tendency for the air to be sucked infrom above, and again there is a slight addition tothe lifting effect. It must be obvious from thisdescription that the poising kingfisher resembles a hori-zontally placed propeller whose bladesreverse every half-revolution. Fig. 42 represents a pied kingfisherpoising not in calm air but in a these conditions the direction ofthe strokes of the wing is no longerho
. Animal flight; a record of observation . ANIMAL Fig. 41. Front view ofpoising kingfisherat beginning ofup-stroke. ment of the up-stroke. Owing to their movement,there must be a tendency for the air to be sucked infrom above, and again there is a slight addition tothe lifting effect. It must be obvious from thisdescription that the poising kingfisher resembles a hori-zontally placed propeller whose bladesreverse every half-revolution. Fig. 42 represents a pied kingfisherpoising not in calm air but in a these conditions the direction ofthe strokes of the wing is no longerhorizontal but slightly inclined to thehorizon. The arrow W represents thewind direction. The arrow R representsthe direction of the propelling effectof the wings. As in the first case itmust be obvious that propelling work is being doneon the up-stroke besides on the down-stroke. I was once watching a pied Xji^kingfisher poising in a calm. It was iili^struck by a puff of wind, as shown -^-> \ A^Sby ripples that appeared on the waterbelow it. The conseq
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectan, booksubjectflight
