PAGE

The wing at all times thoroughly under control,

The natural wing when elevated and depressed must move for-

The wing ascends when the body descends, and vice versâ,

The wing acts upon yielding fulcra,

154

156

159

165

The wing acts as a true kite both during the down and up

Where the kite formed by the wing differs from the boy's kite,

The angles formed by the wing during its vibrations,

The body and wings move in opposite curves,.

166

167

168

THE WINGS OF INSECTS, BATS, AND BIRDS.

Elytra or wing cases and membranous wings; their shape and

uses,

THE WINGS OF BATS.

The bones of the wing of the bat; the spiral configuration of

their articular surfaces,

THE WINGS OF BIRDS.

The bones of the wing of the bird; their articular surfaces,

movements, etc.,

Traces of design in the wing of the bird; the arrangement of

the primary, secondary, and tertiary feathers, etc.,

The wing of the bird not always opened up to the same extent

in the up stroke,

Flexion of the wing necessary to the flight of birds,

Consideration of the forces which propel the wings of insects, .

Speed attained by insects,

Consideration of the forces which propel the wings of bats and

birds,

189

Lax condition of the shoulder-joint in bats and birds,

The wing flexed and partly elevated by the action of elastic

ligaments; the nature and position of said ligaments in

the Pheasant, Snipe, Crested Crane, Swan, etc.,

190

191

The wing acts as an elevator, propeller, and sustainer, both

during extension and flexion,

197

Flight divisible into four kinds,

197

The flight of the Albatross compared to the movements of a

compass set upon gimbals,

199

The regular and irregular in flight,

201

Mode of ascending, descending, turning, etc.,

201

The flight of birds referable to muscular exertion and weight,

Lifting capacity of birds,

The Author's views; his method of constructing and applying

artificial wings, as contra-distinguished from that of Borelli,

How to construct an artificial wave wing on the insect type,

How to construct a wave wing which shall evade the super-

imposed air during the up stroke, .

240

241

Compound wave wing of the Author,

242

How to apply artificial wings to the air,

245

As to the nature of the forces required for propelling artificial

wings,

246

Necessity for supplying the roots of artificial wings with elastic

structures in imitation of the muscles and elastic ligaments

of flying animals,

The artificial wave wing can be driven at any speed-it can

PAGE

247

make its own currents or utilize existing ones,

Compound rotation of the artificial wave wing. The different

parts of the wing travel at different speeds,

251

252

How the wave wing creates currents and rises upon them, and

how the air assists in elevating the wing,

253

The artificial wing propelled at various degrees of speed during

the down and up strokes, .

255

LIST OF ILLUSTRATIONS.

The Engravings are, with few exceptions, from Photographs, Drawings, and Designs by Mr. Charles Berjeau and the Author. Such as are not original are duly acknowledged.

The skeleton of a Deer-(Pander and D'Alton),
Muscular cycle in the act of flexing the arm,

Screws formed by the bones of the wing of the bird, the bones of
the anterior extremity of the Elephant, and the cast of the
interior of the left ventricle of the heart,

The muscular system of the Horse—(Bagg),

21

2225

28

30

The feet of the Deer, Ornithorhynchus, Otter, Frog, and Seal, .
The Red-throated Dragon,

34

35

The Flying Lemur,

35

The Bat,

36

Chillingham Bull with extremities describing figure-of-8 movements,

37

Double waved tracks described by Man in walking,

39

Horse in the act of trotting,

41

Footprints of the Horse in the walk, trot, and gallop--(Gamgee),
Skeleton of the Ostrich-(Dallas),

The positions assumed by the extremities and feet in walking

The elliptical, looped, and spiral tracks made in swimming,

76

81

The feet of the Swan as seen in the open and closed condition,
The foot of the Grebe with swimming membrane-(Dallas),
Double waved track described by the feet of swimming birds, .
The flight of the Flying-fish,

.

The wing a lever of the third order,

Figure-of-8 vertical track made by the wing in flight, .

Do. horizontal track,

Feathers and cork flying forward,

94

96

97

97

98

105

107

Partridge with small wings; Heron with large wings,
The wings of the Hawk and Albatross,

126

136, 137

The Green Plover with one wing flexed and the other extended,
Blur or impression produced on the eye by the rapidly oscillat-

ing wing of the insect,

Diagram in which the down and up strokes of the wing of the insect are analysed,

Diagrams illustrating the looped and waved tracks described
by the wing of the insect, bat, and bird,
Figures showing the positions assumed by the wing of the bird
during the up and down strokes (side view),
The positions assumed by the wing of the insect as it hastens
to and fro and describes a figure-of-8 track,

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,

The waved tracks described by the wing and body of the bird

as they alternately rise and fall,

149

157, 163