CHAPTER VII 



THE BREATH OF A BIRD 



jHINK of a mite of a hummingbird shooting 

 southward mile after mile; his singing wings 

 y beginning their throbbing in the cool damp air 

 of an Alaskan fall, whirring through the dr}- heat of des- 

 erts and around the wind-eddied spurs of mountain-ranges, 

 until they hum in the warm atmosphere of Mexico or 

 Brazil, where tiny insects are never lacking throughout 

 the winter! How exquisite an adjustment must exist 

 in his organs; how mankind's engines of locomotion are 

 put to shame! The onh^ comparison of which we can 

 think is with an insect,— a sphinx-moth or a beetle, whose 

 wings of gauze lift and carry their owners so easih', so 

 steadily. It will be interesting to keep this similarity 

 in mind, superficial though it is. 



Birds require, comparatively, a vastly greater strength 

 and "wind" in traversing such a thin, unsupporting 

 medium as air than animals need for terrestrial locomo- 

 tion. Even more wonderful than mere flight is the per- 

 formance of a bird when it springs from the ground, and 

 goes circling upward higher and higher on rapidly beating 

 wings, all the while pouring forth a continuous series of 

 musical notes, the strength of the utterance of which 



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