To see unexcelled poetry in motion on these warming evenings, look into the skies for the darting blue-black forms of swallows flashing in the fading sunlight.

Watch the lifting of slim, swept-back wings, the rapid alternate beating, quickly followed by short glides as graceful forms swirl against the heavens, performing aerial ballets. Swallows' twinkling grace on the wing is often accompanied by soft twitterings of sheer joy.

Typical songbirds fly at about 20 miles per hour, and waterfowl speed to 40. Swallows are even faster. Only the similar-appearing but unrelated swift is, well, swifter. And they regularly cover up to 600 miles just in their daily search for insects. Uncanny navigational skills permit swallows to migrate hundreds of miles across open oceans to and from wintering grounds in faraway South America.

It requires lots of flying and air-borne insects before even these birds of lyric grace and winged mastery can snag enough food to enable them to raise their hatchlings, usually four or five young.

Swallows like to nest in colonies. The largest of swallows, and best known, is the purple martin, which has learned to rely on man to erect houses (or gourds on poles) for its use. The barn swallow prefers a flask-shaped structure created of mud and straw.

Noah, seeking land, released a dove, a swallow and a raven. The dove returned with a branch, the evil raven disappeared, but the swallow built a nest. And farmers know, "When the swallow builds low, you can safely reap and sow."