78 WILD BIRDS 



studying natural flight closely for years, and studying 

 it in many different creatures, I have little faith 

 that these aeroplanes will weather great storms and 

 squalls with safety. We have hardly overcome the 

 water in storm yet it may be a task far harder to 

 ride the air in storm. 



Birds, as fliers, might without much fancy be 

 almost divided into two classes earth birds and 

 air birds. The wing of the house sparrow, the wing 

 of the finch, or of the woodpecker, enables the bird 

 to move with more or less ease from one spot on 

 land to another. The wing of the swift, the swallow, 

 the martin, the seagull and the petrel is to enable 

 the bird to move with complete comfort and ease 

 in the air, to feed and to rest in it, for hours at a 

 stretch. 



Though the earth bird, exceptionally for example 

 on migration becomes a creature of the air, 

 there is a great difference between itself and the 

 air bird. Gatke believed that for migration the 

 bird was endued with special powers of flight and 

 endurance which it lacked at other seasons. I should 

 incline to believe that the will and spirit that fills 

 the bird at this time carries it through. 



To get a good idea of the difference between the 

 earth bird and the air bird, we may watch at this 

 time of year the companies of swallows, house 

 martins, and sand martins that hawk about and 

 gambol at certain favourite spots ; and, whilst 

 watching, compare their action on the wing with 

 that of the sparrows and finches often scattered 



