REPKODUCTION OF MECHANISM OF FLIGHT. 277 



considered, while it is being lowered, as the passive part of the 

 organ, while the external part, that which strikes the air, is 

 the active portion. 



By its very great velocity, the point of the wing must meet 

 with more resistance from the air than any other part of this 

 organ ; whence the extreme rigidity of the large feathers of 

 which it is formed. 



The conditions of decreasing rapidity explain the flexibility 

 which becomes greater and greater in the feathers of those 

 parts of the wing nearer to the body, and at last the great 

 thinness of those at the base or passive part of the wing. 



Let us add that the effect of the kite must be produced at 

 the base of the wing, even while the point strikes the air, so 

 that the bird, as soon as it has acquired its velocity, would 

 be constantly lightened of part of its weight, on account of 

 this inclined plane. 



The reproduction of the mechanism of '/light now occupies the 

 minds of many experimenters, and we hesitate not to own 

 that we have been sustained in this laborious analysis of the 

 different acts in the flight of the bird, by the assured hope of 

 being able to imitate, more or less imperfectly, this admirable 

 type of aerial locomotion. We have already met with some 

 success in our attempts, which have been interrupted during 

 the last two years. 



Winged apparatus has been seen in our laboratory, which 

 when adapted to the frame-work which had held the bird, 

 gave it a rather rapid rotation. But this was only a very 

 imperfect imitation, which we hope shortly to improve. 

 Already a young and ingenious experimentalist, Mons. 

 Alphonse Penaud, has obtained much more satisfactory results 

 in this direction. The problem of aerial locomotion, formerly 

 considered a Utopian scheme, is now approached in a truly 

 scientific manner. 



The plan of the experiments to be made is all traced out : 

 they will consist in continually comparing the artificial instru- 

 ments of flight with the real bird, by submitting them both 

 to the modes of analysis which we have described at such 

 length ; the apparatus will, from time to time, be modified 

 till it is made to imitate these movements faithfully. For 



