XXV 
HIS WINGS AND TAIL 
A BIRD’s wing does not look much like our 
arm and hand, yet the bones show that they are 
the same. The bird has a shoulder, elbow, and 
wrist, as we have. He even has fingers, though 
they are so covered up by feathers that one would 
never know it. He has not so many fingers as 
we have, and they are not movable like ours. 
A bird’s wing is a wonderful flying-machine, 
which men have been trying to imitate these 
many years. It is made of long stiff feathers, 
which fold down smoothly over one another at 
his side when he is resting, but can spread in an 
instant into a broad fan, to beat the air and 
carry him away. 
One would not think that feathers could have 
so much power; but when the wing is spread, the 
barbs of the feathers hook together with tiny 
hooks, so small a microscope is needed to see 
them ; and that, together with the edges lapping 
over each other, makes them almost like one 
solid surface. 
