ocean of the air. It is, I think, the cessation of all effort on the bird's part which makes the great loveliness here. The impetus has been gained in flight before—acres of moorland away sometimes—it "cometh from afar." The upward fall, the delicious, crested curl and soft, sinking swoon to the earth are all rest—rhythmical, swift-moving rest.
Another curious and extremely pretty performance—a familiar bar of that thread of melody, that "main theme" of the "movement"—is when two birds, one just a little behind the other, and at slightly different elevations, both make the same movements, in quick succession, the bird behind mimicking the one in front of him in a kind of aerial follow-my-leadership. Does the one pause and hang on extended wings that rapidly beat the air, the other does so too. Does it sail on a little, and then make a sideway dive, it is imitated in the same way, and thus, often for quite a little while, the two will understudy each other—for each, I think, may alternately become the leader. Again—if this is not merely a development of the above—two of them will hover on outstretched wings directly over and almost touching each other. Sometimes, indeed, they do touch, for the bird that is stretched above is continually trying to strike down on the other one with his wings, and often succeeds by making a sudden little drop on to him—a drop which is only of an inch or so—quite covering him up for a moment. Then, disjoining, they will flap along for some while, still close together, flashing out alternately dark and silver, as if showing their glints to each other, till in two "dying falls" they sweep apart, and skim the ground and double-loop the heavens.
