THE UNCHARTED SKY 155 



came a terrific snowstorm, in which several million 

 birds were lost in one night, one of the greatest 

 bird tragedies which has come under the eyes of a 

 competent observer. 



*' Migration is Nature's great and final test. 

 To-day, as always, the stern task of life weeds out 

 the weak, the dull and foolhardy, as clearly as it 

 did a million years ago. If it is a picture of 

 beauty, it is one of stem beauty, of something like 

 heroic endeavor, a crusade every year which only 

 the chivalry of bird-land survive. Those birds 

 who come to us in the spring of the year have won 

 their spurs in the great test. 



** 'Both spring and fall phases of the great 

 movement,' says Gatke, 'unfold a picture of bird 

 life of incomprehensible grandeur, presenting to 

 our wondering sight myriads of these restless 

 wanderers hastening during the long dark nights 

 of Autumn or the starless midnight hours of 

 spring, by many intersecting paths, to the far-off 

 winter quarters or the nesting homes ; each species 

 following, at higher or lower regions of the sky, a 

 sure and definite road, not marked out for them 

 along river courses or mountain chains, but one 

 that leads them, independent of every physical 

 configuration of the earth's surface, and at heights 



