X CONTEXTS. 







PAGE 



insects Construction of an artificial insect which moves hori- 

 zontally Change of ]>lane in flight 196 



CHAPTER III. 



OF THE FLIGHT OF BIRDS. 



Conformation of the bird with reference to flight Structure of the 

 wing, its curves, its muscular apparatus Muscular force of the 

 bird, rapidity of contraction of its muscles Form of the bird ; 

 stable equilibrium, conditions favourable to change of plane 

 Proportion of the surface of the wings to the weight of the body 

 in birds of different she 209 



CHAPTER IV. 



OF THE MOVEMENTS OF THE WING OF THE BIRD 



DURING FLIGHT. 



Frequency of the movements of the wing Relative durations of its 

 rise and fall Electrical determination Myographical determi- 

 nation Trajectory of the bird's wing during flight Construc- 

 tion of the instruments which register this movement Experi- 

 mentElliptical figure of the trajectory of the point of the 

 wing 226 



CHAPTER V. 



OF THE CHANGES IN THE PLANE OF THE BIRD'S WING 



AT DIFFERENT POINTS IN ITS COURSE. 

 New determination of the trajectory of the wing Description of 

 apparatus Transmission of a movement by the traction of a 

 thread Instruinent and apparatus to suspend the bird Experi- 

 ment on the flight of a pigeon Analysis of the curves 

 Description of the apparatus intended to give indications of the 

 changes in the plane of the wing during flight Relation of 

 these changes of plane to the other movements of the wing . 2-11 



CHAPTER VI. 



RE-ACTIONS OF THE MOVEMENTS OF THE WING ON 

 THE BODY OF THE BIRD. 



Re-actions of the movements of the wing Vertical re-actions in 

 different species ; liori/ontal re-actions or changes in the 

 rapidity of flight; simultaneous study of the two onlei 

 relictions Theui\ ol the flight uf the bird -P.i.-sive and active 

 parts of the wing Reproduction of the HHch.miMii ol the flight 

 of the I, ml . . 204 



