the one wing as compared with the other; or to keep the one wing extended while the other is partially flexed. The neck, feet, and tail may or may not contribute to this result. If the bird wishes to rise, it tilts its entire body (the neck and tail participating) in an upward direction (fig. 59, p. 126; fig. 102, p. 183); or it rises principally by the action of the wings and by muscular efforts, as happens in the lark. The bird can in this manner likewise retain its position in the air, as may be observed in the hawk when hovering above its prey. If the bird desires to descend, it may reverse the direction of the inclined plane formed by the body and wings, and plunge head foremost with extended pinions FIG. 106. The Pigeon (Treron bicincta, Jerdon), flying downwards and turning prior to alighting. The pigeon expands its tail both in ascending aud descending.-Original. (fig. 106); or it may flex the wings, and so accelerate its pace; or it may raise its wings and drop parachute-fashion (fig. 55, p. 112; g, g of fig. 82, p. 158); or it may even fly in a downward direction-a few sudden strokes, a more or less abrupt curve, and a certain degree of horizontal movement being in either case necessary to break the slightly upwards, at the same time raising his left side and wing, and lowering the right in proportion to the sharpness of the curve he wishes to make, the wings being kept quite rigid the whole time. To such an extent does he do this, that in sweeping round, his wings are often pointed in a direction nearly perpendicular to the sea; and this position of the wings, more or less inclined to the horizon, is seen always and only when the bird is turning."-" On some of the Birds inhabiting the Southern Ocean." Ibis, 2d series, vol. i. 1865, p. 227. giddy perch, until inclination or desire prompts him to plunge into or soar above the drenching mists which, shapeless and ubiquitous, perpetually rise from the hissing waters of the nether caldron. which enables them to act through its instrumentality with marvellous dexterity and power, and to expend or reserve their energies, which they can do with the utmost exactitude, in their apparently interminable flights. Lifting-capacity of Birds.—The muscular power in birds is usually greatly in excess, particularly in birds of prey, as, e.g. the condors, eagles, hawks, and owls. The eagles are remarkable in this respect-these having been known to carry off young deer, lambs, rabbits, hares, and, it is averred, even young children. Many of the fishing birds, as the pelicans and herons, can likewise carry considerable loads of fish ;1 and even the smaller birds, as the records of spring show, are capable of transporting comparatively large twigs for building purposes. I myself have seen an owl, which weighed a little over 10 ounces, lift 21⁄2 ounces, or a quarter of its own weight, without effort, after having fasted twenty-four hours ; and a friend informs me that a short time ago a splendid osprey was shot at Littlehampton, on the coast of Sussex, with a fish 5 lbs. weight in its mouth. There are many points in the history and economy of birds which crave our sympathy while they elicit our admiration. Their indubitable courage and miraculous powers of flight invest them with a superior dignity, and secure for their order almost a duality of existence. The swallow, tiny and inconsiderable as it may appear, can traverse 1000 miles at a single journey; and the albatross, despising compass and landmark, trusts himself boldly for weeks together to the mercy or fury of the mighty ocean. The huge condor of the Andes lifts himself by his sovereign will to a height where no sound is heard, save the airy tread of his vast pinions, and, from an unseen point, surveys in solitary grandeur the wide range of plain and pasture-land;2 while the bald eagle, nothing daunted by the din and indescribable confusion of the queen of waterfalls, the stupendous Niagara, sits composedly on his 1 The heron is in the habit, when pursued by the falcon, of disgorging the contents of his crop in order to reduce his weight. 2 The condor, on some occasions, attains an altitude of six miles. |