98 
RAPIDITY OF FLIGHT. 
Grannet and other diving birds, the Frigate-Bird 
holds its neck and feet in a horizontal direction ; 
striking the upper column of air with its wings, then 
raising and closing them one against the other above 
its back, it darts on the flying-fish with such skill 
and certainty, as almost invariably to ensure suc- 
cess. 
Most travellers who have visited Constantinople, 
by the passage of the Dardanelles and the Sea of 
Marmora, may have noticed a bird not quite so 
large as a Pigeon, abundant in that neighbourhood, 
though occasionally seen in other parts of the archi- 
pelago, as at Napoli and Yourla, which must have 
excited their curiosity and surprise. u Every day,” 
says one of the many authors who have noticed it, 
“ they are to be seen in numerous flocks, passing up 
and down the Bosphorus with great rapidity. When 
they arrive either at the Black Sea, or Sea of Mar- 
mora, they again wheel about, and return up the 
channel, and this course they continue, without a 
moment's intermission the whole day. They are 
never seen to alight either on land or water ; they 
never for a moment deviate from their course, or 
slacken their speed ; are never known to search for, 
or take any food ; and no visible cause can be 
assigned for the extraordinary and restless instinct 
by which they are haunted. They fly very near the 
surface of the water ; and if a boat meets a flock of 
them, they either rise a few feet over it, or it 
divides them like a wedge. Their flight is remark- 
ably silent ; and, though so numerous and so close, 
the whirr of their wings is scarcely ever heard. 
They are so abundant in the Sea of Marmora, that 
