The most beautiful flyer we ever see against our skies is the unsavory buzzard. He is the winged embodiment of grace, ease, and leisure. Judging from appearances alone, he is the most disinterested of all the winged creatures we see. He rides the airy billows as if only to enjoy his mastery over them. He is as calm and unhurried as the orbs in their courses. His great circles and spirals have a kind of astronomic completeness. That all this power of wing and grace of motion should be given to an unclean bird, to a repulsive scavenger, is one of the anomalies of nature. He does not need to hurry or conceal his approach; what he is after cannot flee or hide; he has no enemies; nothing wants him; and he is at peace with all the world. The great condor of South America, in rising from the ground, always faces the wind. It is often captured by tempting it to gorge itself in a comparatively narrow space. But if a strong enough wind were blowing at such times, it could quickly rise over the barrier. Darwin says he watched a condor high in the air describing its huge circles for six hours without once flapping its wings. He says that, if the bird wished to descend, the wings were for a moment collapsed; and when again expanded, with an altered inclination, the momentum gained by the rapid descent seemed to urge the bird upwards with the even and steady movement of a paper kite. In the case of any bird _soaring_, its motion must be sufficiently rapid for the action of the inclined surface of its body on the atmosphere to counterbalance its gravity. The force to keep up the momentum of a body moving in a horizontal plane in the air (in which there is so little friction) cannot be great, and this force is all that is wanted. The movement of the neck and body of the condor, we must suppose, is sufficient for this. However this may be, it is truly wonderful and beautiful to see so great a bird, hour after hour, without any apparent exertion, wheeling and gliding over mountain and river. The airplane has a propelling power in its motor, and it shifts its wings to take advantage of the currents. The buzzard and condor do the same thing. They are living airplanes, and their power is so evenly and subtly distributed and applied, that the trick of it escapes the eye. But of course they avail themselves of the lifting power of the air-currents.