BIRD 



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BIRD 



place, but the endurance of some of the smaller 

 birds is surprising. Apparently feeble birds, that 

 usually confine their flight to short dashes from 

 bush to bush, may during the migrating season 

 cover in a single flight distances ranging from 

 500 to 2,000 miles. Some birds, as the yellow- 

 legs, migrate in the fall from the Arctic regions 

 to Southern South America, and return in the 

 spring, thus making each year journeys amount- 

 ing to 16,000 miles. See subtitle, Migration of 

 Birds, below. 



Just how rapidly they fly during these jour- 

 neys there is wide difference of opinion. It 

 may safely be stated that no land animal can 

 move nearly as rapidly as these dwellers in the 

 air, but it seems likely that their speed has 

 been exaggerated by some writers. Carrier 

 pigeons, not the very fleetest of birds, can keep 

 up for hours an average of fifty-five miles an 

 hour; an eagle can rise out of sight in less 

 than three minutes, and thus, according to 

 calculations, must be able to fly at least sixty 

 miles an hour. But it seems probable that 

 the average speed of birds is not more than 

 thirty or forty miles an hour. 



The flight of birds, their ability to live in 

 an element peculiarly their own, has been an 

 inspiration to inventors as well as to poets. 

 For their flight clearly proved that solid bodies 

 of considerable weight could be held suspended 

 in the air if only the right sort of "wings" 

 could be constructed, and all the attempts at 

 building flying machines have grown out of 

 this perception. From Daedalus (which see), 

 who made wings of feathers cemented with 

 wax and flew with them over the sea, to the 

 successful maker of the most complete aero- 

 plane all have had constantly before them the 

 example of the birds. 



Feathers. That birds are among the most 

 beautiful objects in nature is due not only to 

 their grace, but to their clothing of feathers. 

 These feathers, while they take the place of 

 the hair that covers the higher animals, do not 

 grow from practically every part of the body, 

 as does a cat's fur, for instance. They grow 

 in certain definite areas or patches, and the 

 spaces between may be bare or covered with 

 down. Usually, however, the feathers overlap 

 enough to furnish a complete coat. The wing 

 and tail feathers are always the largest and 

 strongest. 



The wonderful adaptations which nature is 

 capable of are plainly to be seen in the feathery 

 coats or plumage of birds. Thus the birds 

 which live in a warm climate and do not fly, 



like the ostrich or the cassowary, have fewer 

 and thinner feathers than do the birds of 

 colder regions. A thick covering is not needed 

 as protection; strong quills are not needed -for 

 beating the air and the bird therefore has 

 neither. In any water fowl is seen the same 

 wise provision a special gland exists for the 

 secretion of oil, with which the bird oils its 

 plumage and thus prevents the water from 

 reaching the body and the feathers from be- 

 coming wet and heavy. "Like water from a 

 duck's back" is the common proverb which has 

 grown out of this peculiarity. 



The difference in color which often exists 

 between the male and the female bird of 

 the same species is another example of this 

 same wonderful adaptation. At the mating 

 season the male must be attractive, if at no 

 other time, and therefore it is true of many 

 birds as of the bobolink that 



Robert of Lincoln is gayly drest, 



Wearing a bright, black, wedding coat ; 

 White are his shoulders and white his crest ; 



while 



Robert of Lincoln's Quaker wife, 



Pretty and quiet, with plain brown wings, 



Passing at home a patient life, 



Broods in the grass while her husband sings. 



Some of these mating-season coats of the male 

 birds are gorgeous in the extreme, but many 

 of them are shed when the nesting season is 

 over. 



Molting. Almost all birds shed their feathers 

 at least once a year. Anyone who has had a 

 canary or other cage-bird has watched the 

 process often, and has noticed how the best 

 songster fails at that time to sing. Nor will 

 the barnyard fowl, however well fed, lay eggs 

 during this shedding or molting time, as it is 

 called. The feathers never all drop off at once, 

 as do the leaves from a tree, to make room 

 for the new plumage, but the old, worn 

 feathers gradually give place to new. In some 

 birds the molting is partial, the wing and tail 

 feathers remaining in place; in others com- 

 plete, those strong feathers falling also. Some 

 birds, like the bobolink mentioned above, 

 have a gay plumage for the mating season and 

 a duller one thereafter 



Robert of Lincoln at length is made 



Sober with work and silent with care ; 

 Off is his holiday garment laid ; 



and such birds have of necessity two molting 

 seasons in a year. 

 Senses. As compared with other animals 





