112 THE OCEAN. 
to consume twenty-two thousand of the young birds 
every year, besides eggs. They are powerful birds 
upon the wing, and pursue with much eagerness the 
shoals of herrings and pilchards, on which they 
pounce with the perpendicular descent of a stone. 
Buchanan conjectures that the Gannets destroy 
more than one hundred millions of herrings an- 
nually. In flying over Penzance some years since, 
a Gannet’s attention was arrested by a fish lying on 
a board. According to custom, down he swooped 
on the prey; but his imprudence cost him his life; 
and it was found that from the impetus of his de- 
scent, the bill had quite transfixed the board, though 
an inch and a quarter in thickness. The fishermen 
take advantage of this habit, to allure the bird to 
its destruction; for they fix a fresh herring to a 
board, and draw it after a sailing boat with some 
rapidity ‘through the waves; by which many are 
killed in the manner just narrated. The apparatus 
by which this bird is furnished for its aérial powers, 
as well as for aiding its arrowy descent, is very beau- 
tiful and instructive. Professor Owen, by inserting 
a tube into the windpipe, was enabled to inflate the 
whole body with air, and found that air-cells com- 
municating with each other, pervaded every part, 
separating even the rouscles from each other, and 
isolating the very vessels and nerves; and penetrat- 
ing the bones of the wing. A large air-cell was 
found to be placed in front of the forked-bone, or 
clavicles, which was furnished with muscles, whose 
action was instantaneously to expel the air, and thus 
in a moment to deprive the bird of that buoyancy, 
