THE NEW STUDY OF BIRDS 



of light, and I have detected two complete loops 

 of a goldfinch silhouetted against the globe of 

 glowing silver. Careful preparation may yield 

 knowledge of flying height — estimated from the 

 apparent size of the bird. 



When the living stream of birds dwindles away, 

 if one's wonder turns to moon mountains or to 

 planets and nebulae, then has ornithology given 

 place to a very worthy substitute. 



Cultivate the habit of looking up, even in the 

 midst of a great city, and the occasional glimpse 

 of a high circling hawk or a chevron of geese will be 

 good for whatever ails you. 



The difficulties of this study of the night flights 

 of birds are greater even than those with which 

 astronomers have to contend. We know with 

 more or less certainty where birds breed and where 

 they spend the winter, but the mystery of their 

 going is so great that for many years it was believed 

 that swallows hibernated in the mud. A new 

 phase of bird study has arisen recently and even 

 before the advance of mankind will have stamped 

 out all but a few species, it seems as if we may 

 learn many secrets now hidden. This new thing 

 is tagging, or the placing of a tiny, numbered, 

 light metal band on the leg of a bird. This anklet 

 in no way discommodes the wearer and by the 

 lucky accident of the bird being secured in a far 

 distant country or retrapped at its home another 

 season, we are accumulating a host of interesting 

 facts. Thus the same white- throated sparrow has 



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