353 THE STRUCTURE AND LIFE OF BIRDS chap. 



the ocean till they reach the West Indies. Even 

 then, it is said, they will sometimes pass the first 

 islands they reach and press on to more distant ones. 

 From Nova Scotia to Hayti, the nearest West 

 India Island available, is over 1,700 miles. Either, 

 then, they fly at an almost incredible pace, or else 

 they remain upon the wing an almost incredible time. 

 But though it is easy to say that such a feat is 

 incredible, it is very difficult to get over the evidence. 

 One witness after another declares that he has seen 

 flocks of them flying southward, several hundreds of 

 miles to the east of the Bermudas, on which islands 

 they alight only if the weather is unfavourable. 1 



The Beam-wind Theory. 



Several very good observers, among them Herr 

 Gatke himself, are of opinion that migratory birds 

 dislike flying with a tail wind, i.e. with the wind 

 directly behind them, and that what they prefer is 

 a beam wind, i.e. a wind striking them upon the 

 shoulder. A comical explanation of this supposed 

 fact used to be given — that a wind from behind 

 ruffled up the bird's feathers. But as he is moving 

 with the wind, and necessarily at a greater pace, since 

 in addition to that of the wind he has the velocity 

 due to his own efforts, this explanation will not hold. 

 Besides this, keepers of Homer Pigeons seem all to 

 agree that their birds make much better times when 



1 See The Naturalist in Bermuda, by H. M. Jones, p. 72; and 

 North American Birds, by Baird, Brewer, and Ridgway, vol. i. 

 p. 140. 



