AVIATORS 183 



amount of noise made in flying is caused partially 

 by the hardness or softness of the pinion-feathers, 

 and partly from the relative rapidity or slowness 

 of the strokes of the wings. Quick fliers move 

 with a rushing, whistling sound; slower fliers, si- 

 lently. The former motion is found with short- 

 winged, and the latter with broad-winged birds." 



Thus we see that bird aviators are adepts at every 

 known form of air navigation, from that which is 

 carried on by regular beats of the wings to soaring, 

 gliding, hovering, dropping, plunging, and zigzag- 

 ging. Storks, eagles, crows, and pelicans are skilled 

 in the art of soaring, whUe examples of gliders may 

 be found among the pigeons and falcons. Condors 

 sometimes soar to a giddy height over mountains, 

 and then hover in the clouds; buzzards are also 

 gifted in this art. The most skilled in the art of 

 hovering is the kestrel. This is the antithesis of 

 soaring. While hovering, the kestrel remains poised 

 over the same spot apparently motionless, but in 

 fact the wings are beating with great rapidity. The 

 humming-bird is a professional hoverer. The ever- 

 glade kite has a most unusual way of anchoring it- 

 self in the air. It has learned to hover motionless 

 at a great height, with the exception of its expanded 

 tail, which moves from side to side. This enables 

 it to remain stationary for a long period. 



