NONSUCH 



not forced to move by oncoming frost, some are con- 

 tent to shift a few miles southward, others to cross 

 mountain ranges and wide stretches of open ocean, 

 to winter in unfamiliar torrid jungles. If our fancied 

 glow of the instinct was a reality, our spring and 

 autumn nights would show an unending blaze of 

 avian meteors which would dim the moon and stars. 

 After exhausting our explanations of the means of 

 guidance, such as landmarks, sea currents, winds, 

 stars and a magnetic sense, we must, in some in- 

 stances at least, fall back on an inexplicable sense 

 of direction. And when we have taken refuge in 

 this pleasantly all-comprehensive phrase, we re- 

 member those species in which the young migrate 

 before their parents — and rather willingly change 

 the subject. 



At least we have moderated our ideas as to al- 

 titude and speed. Instead of a height of three miles 

 above the earth, we know from airplane and other 

 observations, that nocturnal migrants seldom aver- 

 age more than a half mile height. In the daytime, 

 however, flocks of storks, geese and plover have 

 been seen two miles up going full speed. The record 

 is perhaps several geese in the western Himalayas 

 photographed at an estimated height equal to that 

 of Mount Everest. 



Until stop-watches and airplanes gave us definite 

 data we were willing to accept with wondering 

 credulity a speed of two hundred and forty miles 

 an hour attributed to many birds. The cruel exacti- 

 tude of definite observation has brought this down 



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