F. W. HE ABLE Y : WIND AND FLIGHT. 121 



to the patch to which they wished (or I imagined they 

 wished) to go. Of this I saw many instances. 



Rooks very much enjoy a stiff breeze. You can see 

 them over their rookery hanging in air, head towards the 

 wind. Sometimes they turn and fly with it, but, as far as 

 I have observed, they do not equal it in pace, and so they 

 lose altitude. It impinges on their backs, and so tends to 

 drive them downwards. 



If a bird flying with the wind only equals its velocity, 

 he is part of the moving current, as a balloon is. The air 

 does not resist, and consequently does not support him. 

 If his pace is not equal to that of the wind, not only does 

 it not support him, but it assists gravitation. It would 

 also ruffle his plumage, a thing he much dislikes. It may 

 be urged that, since he is part of the moving current, he 

 has only to ply his wings vigorously, and he will, as a 

 matter of course, outpace the wind, and so will have no 

 difficulties. But he must first get started. He cannot 

 rise facing in the direction in which the wind blows. He 

 rises with the wind in his face, thus getting it to help him. 

 When he has reached the altitude he wants, he must turn, 

 and at first will have no pace to speak of. The wind will 

 buffet him, and, striking on his back, send him downward. 

 Moreover, and perhaps this is the greatest difficulty, wind 

 conies in gusts. Though his own velocity may be superior 

 to the wind's average velocity, yet a sudden gust may 

 deprive him of this superiority, may inconvenience him, 

 and cause him to lose altitude. 



When, during a high wind, a bird wishes to alight, he 

 descends with the wind, then, when he nears the ground or 

 his perch, he wheels round and faces it. The resistance of 

 the air checks him and steadies him. A bird's mode of 

 alighting is always a fine thing to see. The outspread 

 wings, even the little bastard wings extended (a back 

 stroke being thrown in if necessary), prevent all jar, and 

 as he comes to earth he is, unlike man-made flying 

 machines, under perfect control. 



(To be continued.) 



