i88 NIGHT MIGRATION 



thirst tend further to allay the sense of disquiet, so 

 that the traveller is able to descend to earth to feed 

 and rest until, restored, the pain returns to urge him 

 on his way. 



It seems marvellous to me, this account of a pet 

 cuckoo driven while in captivity — stung, we may say 

 — into simulated action where action was impossible, 

 by a motive, an impulse, an instinct, beyond aU others 

 in its power over the bird; escaping and flying by 

 night, and night after night, straining towards its 

 distant bourne over a thousand leagues of land and 

 sea, and all the time sitting motionless on the table 

 in a room by the dim light of a reading-lamp ! 



The very fact that strictly diurnal species do travel 

 by night is a proof of the power of the migratory 

 impulse. 



Montagu, the author of the Dictionary of Birds, 

 and an observer of birds all his life, refused to believe 

 that such a thing was possible. He says, truly 

 enough, that there is nothing birds that see and 

 have their active time by day fear so much as the 

 dark. At the approach of night they hide themselves 

 away and fall asleep, and if disturbed are in terror 

 and act as if blind or senseless. Yet we know that 

 he was wrong, that many diurnal species (and I 

 would place all or most migratory cuckoos among 

 them) do travel by night, and that the impulse 

 to escape, to rush away, becomes in these night- 

 travellers most active, painful and insistent in the 

 waning light. 



There is another matter closely connected with 



