Swifts fly to an immense height these July evenings, mounting to such an altitude as eventually to disappear out of sight altogether. This curious habit, which is but imperfectly understood, has led to the belief that, instead of roosting in the nest or among the reeds like the swallows, the males, at any rate, spend the night flying about under the stars. This fantastic notion is not, however, likely to commend itself to those who pause to reflect on the incessant activity displayed by these birds the livelong day. So rarely indeed do they alight that country folk gravely deny them the possession of feet, and it is in the last degree improbable that a bird of such feverish alertness could dispense with its night's rest. No one who has watched swifts, swallows and martins on the wing can fail to be struck by the extraordinary judgment with which these untiring birds seem to shave the arches of bridges, gateposts, and other obstacles in the way of their flight by so narrow a margin as continually to give the impression of catastrophe imminent and inevitable. Their escapes from collision are marvellous; but the birds are not infallible, as is shown by the untoward fate of a swallow in Sussex. In an old garden in that county there had for many years been an open doorway with no door, and through the open space the swallows had been wont, year after year, to fly to and fro on their hunting trips. Then came a fateful winter during which a new owner took it into his head to put up a fresh gate and to keep it locked, and, as ill luck would have it, he painted it blue, which, in the season of fine weather, probably heightened the illusion. Back came the happy swallows to their old playground, and one of the pioneers flew headlong at the closed gate and fell stunned and dying on the ground, a minor tragedy that may possibly come as a surprise to those who regard the instincts of wild birds as unerring.