WIND AND FLIGHT 125 
dislike this.” By way of answer we may say that 
an undoubted fact is no better than blank cartridge 
if it does not apply to the particular case. It is true, 
no doubt, that whereas a horse or a cow will always 
turn tail to a strong breeze, a bird always stands 
facing it. I have just seen some forty Starlings on 
a dead poplar tree. All, to a bird, were facing the 
breeze. Gulls or Oyster-catchers may often be seen 
by the seashore all facing to the front like soldiers 
when the word ‘Eyes front!” is given. The 
nictitating membrane protects their eyes from the 
wind, and there is no tumbling of their neat plumage. 
But would such a thing be likely to happen during 
flight from whatever direction the wind was blowing ? 
A bird must have some velocity of his own; he 
cannot be like a leaf carried by the wind ; he is too 
heavy for such a method of travelling, and, were he 
to try it, he would soon descend precipitately to 
earth. But though he necessarily has velocity of 
his own added to that of the gale, it might seem 
possible that a terrific tail-wind might occasionally 
cause difficulty. Though the bird’s body outpaces 
the gale, yet there may be moments when the gale 
overtakes his wings. When the down-stroke is over, 
the wings are moved backward as well as upward 
preparatory to the next stroke, though in long- 
distance horizontal flight the forward and backward 
movement is not very great. The velocity of the 
wind, too, varies from moment to moment, and 
Professor Langley showed that the greater the 
velocity the greater is the irregularity. Even a 
steady wind proves to be gusty when properly tested. 
If, then, the wings happened to be moving backward 
