That the work and experiments of M.Renard in 1884 have sufficiently proved.

But, as has been said, it is not necessary to copy Nature servilely.

Locomotives are not copied from the hare, nor are ships copied from the fish.

To the first we have put wheels which are not legs; to the second we have put screws which are not fins.
And they do not do so badly.

Besides, what is this mechanical movement in the flight of birds, whose action is so complex?
Has not Doctor Marcy suspected that the feathers open during the return of the wings so as to let the air through them?
And is not that rather a difficult operation for an artificial machine?
On the other hand, aeroplanes have given many good results.