A GIFT OF GOD 21 



delightful imagery, the eight is gradually "unravelled" as 

 the flier advances. 



How strictly, how neatly it is cut by a flier whose 

 body is stationary and whose wings are in motion, an 

 exquisite experiment showed ; Marey was actually able 

 to insert a pointed instrument in the middle of each 

 circle or loop of the eight without its touching any 

 part of the wing ! 



But though the tail may cut no figure-of-eight as 

 do the wings, the more I notice the flight of birds, 

 the more I am impressed by the part the tail must be 

 playing. Sit under a tree into which a ringdove is 

 carrying sticks for its nest or food for its young. 

 Looking up at the flier, you notice how the fan of its 

 tail is spread out so that each of the feathers is used 

 to the utmost : every available bit of them is brought 

 into play. There has been a tendency to treat the 

 tail of the bird merely as the steering apparatus, the 

 rudder ; and even the chief authorities on flight seem 

 hardly to have thought of it as auxiliary to the wings. 

 A rudder it may be, but it is part of the sail area too. 

 The instant a small bird springs from the ground the 

 tail is opened and spread to catch and work upon the 

 air. A small bird that has lost its tail rises on the 

 wing with obvious difficulty. The tail seems to act 

 on and work up the air, alike when the hawk is 

 hovering and the house sparrow starting from the 

 road ; the instant the fan is opened, the sail spread, 

 it finds some whiff of air to seize and use for flight. 



