A B I R D L V E R'S YEAR 



see Biscay before leaving Africa." Experi- 

 ments made by Mr. Frank Chapman, in 

 America, with an astronomical telescope 

 directed towards the moon, revealed birds 

 passing at an altitude of from one to five 

 miles. The essential question, however, still 

 remains as to how birds are guided in their 

 wonderful migrations, and the old answer 

 holds much truth when it says that " the 

 finger of God points the way." 



Why birds should migrate is another 

 unsolved problem, for migration is quite 

 distinct from distribution. Our summer 

 visitors leave our shores in autumn, and this 

 is no doubt partly due to the fact that the 

 cold of winter robs them of their food- 

 supply. As regards insects, the actual cold 

 itself would not probably matter so much, 

 provided there were an adequate food-supply 

 of other kinds, for birds found dead in 

 winter have generally died of starvation and 

 not of cold. Doubtless our summer migrants 

 hasten to southern latitudes to escape the 

 winter ; but why should they return to 

 our shores at the very time of year when 

 there is often a great dearth of food and 

 almost winter-like conditions to greet them, 



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