. Animal locomotion or walking, swimming, and flying : with a dissertation on aëronautics. ed, so thatcomparatively small wings can be made to elevate a compa-ratively heavy body, if the speed only be increased Flight, therefore, as already indicated, is a ques- 1 The grebes among birds, and the beetles among insects, furnish example*where small wings, made to vibrate at high speeds, are capable of elevatinggreat weights. 13G ANIMAL LOCOMOTION, tion of power, speed, and small surfaces versus measurements of wing, area, and minute calculationsof speed, can conse
. Animal locomotion or walking, swimming, and flying : with a dissertation on aëronautics. ed, so thatcomparatively small wings can be made to elevate a compa-ratively heavy body, if the speed only be increased Flight, therefore, as already indicated, is a ques- 1 The grebes among birds, and the beetles among insects, furnish example*where small wings, made to vibrate at high speeds, are capable of elevatinggreat weights. 13G ANIMAL LOCOMOTION, tion of power, speed, and small surfaces versus measurements of wing, area, and minute calculationsof speed, can consequently only determine the minimum of wing for elevating the maximum of weight- -flight being attainable within a comparatively wide range. Wings, their Form, etc.: all Wings Screws, structurally andfunctionally.—Wings vary considerably as to their generalcontour; some being falcated or scythe-like, some oblong,some rounded or circular, some lanceolate, and some All wings are constructed upon a common type. Theyare in every instance carefully graduated, the wing tapering d p. Fig. 61.—Eight wing of the Kestrel, drawn from the specimen, while beingheld against the light. Shows how the primary (b), secondary (a), and ter-tiary (c) feathers overlap and buttress or support each other in every direc-tion. Each set of feathers has its coverts and subcoverts, the wing beingconical from within outwards, and from before backwards, d, e, /Anterioror thick margin of wing, b, a, c Posterior or thin margin. The wing of thekestrel is intermediate as regards form, it being neither rounded as in thepartridge (fig. 96, p. 176), nor ribbon-shaped as in the albatross (lig. 62), norpointed as in the swallow. The feathers of the kestrels wing are unusuallysymmetrical and strong. Compare with figs. 92, 9-4, and 96, pp. 174, 175, and1*76.—Original. from the root towards the tip, and from the anterior marginin the direction of the posterior margin. They are of agenerally triangular for
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