86 
rendering itself light ox 
mendous rapidity. 
THE WING. 
- heavy at its will, of admitting more or less 
of air into its expressly constructed 
reservoirs. Would it grow light, it 
inflates its dimension, while dimin- 
ishing its relative weight; by this 
means it spontaneously ascends in 
a medium heavier than itself. To 
descend or drop, it contracts itself, 
grows thin and small; _ cutting 
through the air which supported 
and raised it in its former heavy 
condition, Here lay the error, 
the cause of man’s fatal ignorance. 
He assumed that the bird was a ship, 
nota balloon. He imitated the wing 
only; but the wing, however skilfully 
imitated, if not conjoined with this 
internal force, is but a certain means 
of destruction. 
But this faculty, this rapid inhal- 
ation or expulsion of air, of swim- 
ming with a ballast variable at plea- 
sure, whence does it proceed? From 
an unique, unheard-of power of re- 
spiration. The man who should in- 
hale a similar quantity of air at once 
would be suffocated. The bird’s 
lung, elastic and powerful, quaffs it, 
grows full of it, grows intoxicated 
with vigour and delight, pours it 
abundantly into its bones, into its 
aerial cells. Each aspiration is re- 
newed second after second with tre- 
The blood, ceaselessly vivified with fresh air, 
