Title: Animal locomotion, or Walking, swimming, and flying, with a dissertation on aëronautics
Identifier: animallocomotio00pett (find matches)
Year: 1874 (1870s)
Authors: Pettigrew, James Bell, 1834-1908
Subjects: Animal locomotion; Aeronautics
Publisher: New York, D. Appleton & company
Contributing Library: Smithsonian Libraries
Digitizing Sponsor: Biodiversity Heritage Library

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PKOailESSION IN OR THROUGH THE AIR. 125 are slow; in small-winged ones comparatively very rapid. This shows that flight may be attained by a heavy, powerful animal with comparatively small wings, as well as by a lighter one with enormously enlarged wings. While there is apparently no fixed relation between the area of the wings and the animal to be raised, there is, unless in the case of sailing birds,^ an unvarying relation between the weight of
Text Appearing After Image:
Fig. 58.—TJnder-surface of large beetle (Goliathus micans), with deeply con- cave and comparatively small wings (compare with butterfly, fig. 57), shows that the ncrvures (r, d, e, /, n, n, n) of the wings of the beetle are arranged along the anterior margins and tlironghoiit the substance of the wings generally, very much as the bones of the arm, forearm, and hand, are in the wings of the bat, to which they bear a very marked resemblance, both in their shape and mode of action. The wings are folded upon themselves at the point e during repose. Compare letters of this figure with similar letters of fig. 17, p. ZQ.—Original. the animal, the area of its wings, and the number of oscilla- tions made by them in a given time. The problem of flight thus resolves itself into one of weight, power, velocity, and small surfaces; versus buoyancy, debility, diminished speed, 1 In birds which skim, sail, or glide, the pinion is greatly elongated or ribbon-shaped, and the weight of the body is made to operate upon the in- clined planes formed by the wings, in such a manner that the bird when it has once got fairly under weigh, is in a measure self-supporting. This is especially the case when it is proceeding against a slight breeze—the wind and the inclined x^lanes resulting from the upward inclination of the wings reacting upon each other, with this very remarkable result, that the mass of the bird moves steadily forwards in a more or less horizontal direction.

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