I like that phrase as describing the flight of a bird. It is so literally what the creature does. A bird is not superior to gravitation. But for that force he would be the helpless victim of every little breeze, like a balloon, which is unable to shape a course or do anything but float helplessly before the wind. The balloon floats because it is lighter than the air, but the air which the bird displaces is lighter than he, and he only moves in it by virtue of his ability to extract from it, by the motion of his wings, sufficient recoil to propel himself forward. He rises, as do we humans, by means of that which resists him ❧ I love to watch the seagulls. They do this so perfectly, and seem to delight to give us lessons in ærial navigation as they dip and whirl and call about the steamers, on the Bay. Their wings are so easy to study while in action. The first joint, to where the wing bends back and outward, is strong and compact, cup shaped underneath. The second joint tapers. The feathers are long and do not overlap so closely as do those of the first joint, and at the free end they spread out and turn upward. The upper surface of the wing is convex, the lower surface concave. In flying the wings are thrown forward and downward. Flying is not a flapping of the wings up and down, and if a bird were to strike its wings backward and downward, as its manner of flight is so often pictured, it would turn a forward somersault in the air. Structurally the wing of a bird is a screw. It twists in opposite directions during the up and down strokes, and describes a figure of 8 in the air. The bird throws its wings forward and downward. The air is forced back and compressed in the cup-shaped hollows of the wings, and these latter, by the recoil thus obtained, drag the body forward ☙ This resistance of the air is absolutely essential to flight. We who think that, but for the buffetings of hard fate, we, too, might soar high and fly free in the upper realm of endeavor, should watch the efforts of the birds in a calm. We shall scarcely see them flying. If impelled to flight, by necessity, the process is a most laborious one. There being no resisting wind on which to climb (birds always fly against the wind) the climber must, by the rapid action of his wings, establish a recoil that will send him along. Watch the little mud-hen, flying close to the surface of the water, ready to dive the instant its timidity takes fright. Its wings vibrate swiftly, unceasingly, for it rarely rises high enough above the water to have advantage of the air currents. For it there are no long, soaring sweeps through the air; no freedom from the labors of its cautious flight. It is a very spendthrift of effort because of the timidity that never lets it rise to the sustaining forces just above its head. To climb the sky is not for him who hugs cover.