I N D EX — continued. 



163 



Scapula, 69 



Shearwater, 133, 134, 139 

 Snipe, 130 

 Soaring, 141-153 



among Mountains, 144 



always over Land, 145 



over Plains, 146 



impossible for small Birds, 



143 

 impossible in horizontal 



wind, 152 

 spiral Movement in, 148, 



151 

 Sparrow-Hawk {see PL xiii), 



32 

 Starling, Prof., 73 



93 (PL xv) 



Stability, 23-37 



Pendulum, 25 



Starting, 48-58 (PL viii), 121- 



124 

 Steering, 59-63 (PL ix) 

 Sternum, 67-69 

 Stork, 19, 20, 101 

 Surface, Area of supporting, 18- 



22 

 Swallow, 19, 20, 98, 106, 128 



Australian, 111 



Swift, 35, 48 



Tacking, Boat, 8, 26 ') 



Tail, use of, in Balancing, 31-34 



Soaring, 150 



Steering, 60 



Temperature, Regulation of, 



159 

 Tern, 64, 94 

 Thienemann, Dr., 107 



Ulna, 80 



Vane, Experiment with, 134 

 Velocity, see Flight. 

 Vertebrae, 76 



Voluntary Adjustments, 29-37 

 Vulture, 144 



Weight and Supporting Surface, 



19 

 Wind and Flight, 107-109, 120- 



153 

 Wind, at High Altitudes, 112- 



117 



Horizontal, 130, 152 



not Uniform in Velocity, 



122-124, 125 

 having an upward Trend, 



130-153 

 Wing {see Area, Surface, Sta- 

 bility), Curve of, 15-18, 25, 



26 



Elasticity of, 27 



as Lever, 38-40 



Rotation of, 51-54 



Shape of {see Pis. xiii- 



xv), 91-96 



Spreading of, 81-86 



Weight of, 75 



Wings, Whir of, 101 

 Wing-strokes, Phases of {see Pis. 



iv.-vii.), 40-47, 84, 85 



Rate of, 50, 99, 144 



Short, 46 



Unequal (PL ii), 30 



Witherby, Mr. H. F., 66 

 Woodpecker, 55, 65 

 Weight, Mr. Wilbur and Mr. 



Orville, 16, 153. 



