. A dictionary of birds . Fig. 0. (From Marey.). the line of flight, so that their under surface looks dowuAvardsand backwards. The exact angle is not known, but it is certainly a small one, and probablyvaries Avith the Aelocity ofthe birds motion. Havingmade the down and forwardstroke, the wing movesbackward, being still ex-tended, and still inclinedslightly backwards. Thediagram indicating a birdflying from left to right,though not to be taken asmore than approximatelyexact, gives an idea of whatis known regarding the tra-jectory of the wing and the inclinations of its plane Avith the axisof
. A dictionary of birds . Fig. 0. (From Marey.). the line of flight, so that their under surface looks dowuAvardsand backwards. The exact angle is not known, but it is certainly a small one, and probablyvaries Avith the Aelocity ofthe birds motion. Havingmade the down and forwardstroke, the wing movesbackward, being still ex-tended, and still inclinedslightly backwards. Thediagram indicating a birdflying from left to right,though not to be taken asmore than approximatelyexact, gives an idea of whatis known regarding the tra-jectory of the wing and the inclinations of its plane Avith the axisof flight. The down stroke, it should be added, takes a longer timethan the up stroke. In making the latter, as can be seen from thefigure (Fig. 8), the wing passes at first backwards, and then, becom-ing partially flexed with a Avhiplike action, it rises upwards, the planeof the wing being altered during the up stroke, so that it looksdown and forward. If the bird be flying fairly rapidly through theair, the up stroke is mainly a passive movemen
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectbirds, bookyear1896
