WILD LIFE OF ORCHARD AND FIELD 



of wedges of geese winging their way through the 

 sky, so far away that they seem no larger than 

 sparrows, is familiar, but lately we have come to 

 know that the little birds also rise to great alti- 

 tudes before undertaking their long flights. Per- 

 sons observing the moon through powerful tele- 

 scopes have recognized flocks of song-birds rushing 

 across its face, and have estimated them to be from 

 fifteen hundred to twenty-five hundred feet above 

 the surface of the earth. In December, 1896, the 

 meteorologists at Blue Hill, Massachusetts, while 

 measuring the altitude of clouds by triangulation, 

 made instrumental obser^^ations of flocks of ducks, 

 and found them to be flying about one thousand 

 feet above the valley, and at the rate of nearly 

 forty-eight miles an hour. There seems no doubt 

 that this altitude is often greatly exceeded, but 

 even it would afford an immensely extensive out- 

 look, and enable birds (which are remarkabl3^ far- 

 sighted) to discover and recognize landmarks far 

 in advance. This is nothing more than an ex- 

 tension of the familiar performance of homing-pig- 

 eons, which rise to about eighteen hundred feet, 

 when liberated one hundred and twenty-five miles 

 beyond any point familiar to them, before strik- 

 ing out homeward, while those set free (as has 



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