rs on the wing, sweeping
along like children on a "merry-go-round" who try to seize a ring, or to
do some other feat, as they pass a given point. If the swift misses the
twig, or it fails to yield to her the first time, she tries again and
again, each time making a wider circuit, as if to tame and train her
steed a little and bring him up more squarely to the mark next time.

Though the swift is a stiff flyer and apparently without joints in her
wings, yet the air of frolic and of superabundance of wing-power is
more marked with her than with any other of our birds. Her feeding and
twig-gathering seem like asides in a life of endless play. Several times
both in spring and fall I have seen swifts gather in immense numbers
toward nightfall, to take refuge in large unused chimney-stacks. On such
occasions they seem to be coming together for some aerial festival or
grand celebration; and, as if bent upon a final effort to work off a
part of their superabundant wing-power before settling down for the
night, they circle and circle high above the chimney-top, a great cloud
of them, drifting this way and that, all in high spirits and chippering
as they fly. Their numbers constantly increase as other members of the
clan come dashing in from all points of the compass. Swifts seem to
materialize out of empty air on all sides of the chippering, whirling
ring, as an hour or more this assembling of the clan and this flight
festival go on. The birds must gather in from whole counties, or from
half a State. They have been on the wing all day, and yet now they seem
as tireless as the wind, and as if unable to curb their powers.

One fall they gathered in this way and took refuge for the night in a
large chimney-stack in a city near me, and kept this course up for more
than a month and a half. Several times I went to town to witness the
spectacle, and a spectacle it was: ten thousand swifts, I should think,
filling the air above a whole square like a whirling swarm of huge black
bees, but saluting the ear with a multitudinous chippering, instead of a
humming. People gathered upon the sidewalks to see them. It was a rare
circus performance, free to all. After a great many feints and playful
approaches, the whirling ring of birds would suddenly grow denser above
the chimney; then a stream of them, as if drawn down by some power of
suction, would pour into the opening. For only a few seconds would this
downward rush continue; then, as if th