“As to the fatigue of the bird from travel, this is now thought to be very slight, as bird flocks that have crossed great bodies of water do not stop to rest, but usually continue many miles inland. It is, undoubtedly, accident or illness that sometimes causes birds to stop for rest on the rigging of vessels or offshore islands.
The Unknown
“Interest in bird migration goes back to a far distant period. Marvellous tales of the spring and fall movements of birds were spun by early observers, yet hardly less incredible are the ascertained facts. Much remains to be learned, and it may be of interest to note a few of the mysteries which still occupy attention. Even the daily flight of a bird is a wonderful thing apart from the endurance required in the long migrations. Though the wings of birds are built on very much the same plan, few species use them in precisely the same manner; while on a windy day the wings assume a dozen different positions in as many seconds, and to watch the flight of a sea-bird, as it rises and trims itself to the wind and then shapes its course, is to be awe-struck by this mysterious power of flight.
“Snap shot pictures of birds on the wing will show you this better than many words. Some birds, like the Hawks and Eagles, can sustain themselves in the air for hours, sailing against the wind without any visible motion of the wings. Others fly both by swift beating and sailing, like the Terns in one of these pictures.
“In short, the differences are so great that the Wise Men can often identify a bird by the sharp outline of its shadow in flight.
“This power of flight has been a subject of wonder for many thousand years; we think and we speculate, but no one has yet learned the secret in its fulness.
“ ‘The way of an eagle in the air! This is too wonderful for me!’ is an expression of this feeling of mystery, recorded in the book of Proverbs. One thing seems quite certain, however—if man ever succeeds in conquering the air and sailing through it, it will not be by the power of any invention of his own, but because he has at least in some degree mastered the knowledge of the flight of the bird and adapted it to his own use.
“The Chimney Swift, that you all know as the Chimney Swallow, is one of the most abundant and best-known birds of the eastern part of the United States. With troops of fledglings, catching their winged prey as they go, and lodging by night in some tall chimney, the flocks drift slowly south, joining with other bands until, on the northern coast of the Gulf of Mexico, they become an innumerable host. Then they disappear. Did they drop into the water and hibernate in the mud, as was believed of old, their obliteration could not be more complete. In the last week in March a joyful twittering far overhead announces their return to the Gulf coast, but the intervening five months is still the Swifts’ secret.
