The wing a lever of the third order, 105 Figure-of-8 vertical track made by the wing in flight, 107 Do. horizontal track, 108 Feathers and cork flying forward, 112 Diagram illustrating how wings obtain their high speed, 120 Butterfly with large wings, 124 Beetle with small wings, 125 Partridge with small wings; Heron with large wings, 126 The wings of the Hawk and Albatross, 136, 137 The Green Plover with one wing flexed and the other extended, 138 Blur or impression produced on the eye by the rapidly oscillating wing of the insect, 139 Diagram in which the down and up strokes of the wing of the insect are analysed, 141 Diagrams illustrating the looped and waved tracks described by the wing of the insect, bat, and bird, 144 Figures showing the positions assumed by the wing of the bird during the up and down strokes (side view), 145 The positions assumed by the wing of the insect as it hastens to and fro and describes a figure-of-8 track, 147 The figure-of-8 curves made by the wing of the bird in flexion and extension, 147 The long and short axes of the wing, 149 The waved tracks described by the wing and body of the bird as they alternately rise and fall, 157, 163 The positions assumed by the wing of the bird during the down and up strokes (front view), 158 Analysis of the movements of the wing, 160, 161 The kite-like action and waved movements of the wing, 166 The Centaur Beetle and Water Bug, 171 The Dragon Fly, 172 The screws formed by the wing of the insect, bat, and bird, 174, 175, 176 The muscles, elastic ligaments, and feathers of the wing of the bird, 181 The flight of the King-fisher, 183 The flight of the Gull, 186 The flight of the Owl, 198 The flight of the Albatross, 200 Pigeon and Duck alighting, 203, 204 Hawk and quarry--(_The Graphic_), 206 The Vauxhall Balloon of Mr. Green, 208 Mr. Henson’s Flying Machine, 212