244 On the Ornithology of Wiits. 
In the other Orders we do not expect to find such wonderful powers 
of sight, for their habits do not require it; yet here too we shall 
often find considerable quickness and extent of vision. The fly- 
catcher will sit perched on a twig, and suddenly dart upon an 
insect passing often at a considerable distance, which we are wholly 
unable to perceive. The bold and sagacious raven and the 
destructive carrion crow have been famed for their far seeing 
propensities: the rook too has the same property, for which cause 
we may constantly see the dull-eyed starlings attaching themselves 
to their society, and relying on these excellent sentinels, feeding in 
greater security. The swift careeringthrough the airon rapid wing 
and dashing past like a meteor, not only can see to steer his way 
clear of all obstacles, but can discern the passing insect, which it 
catches in its mouth as it rushes by. The pigeons mounting high 
into the air, can perceive the grain which they are seeking from an 
almost incredible distance. The redstart will avoid the shot, by 
rising on seeing the flash from the cap; and many of the ducks and 
especially the divers, disappear under water the moment the 
trigger is pulled, seeing the flash and diving almost instantaneously, 
and so escaping the death intended for them. These are a few 
instances of the extraordinary powers of vision belonging to the 
feathered race. An eminent French naturalist has calculated it to 
be about nine times more extensive than that of man; and 
anatomists, after dissecting the eye of the golden eagle, or one of 
that family, whose sight is considered the keenest of all, declare 
that nothing can be conceived more perfect than the structure. 
The eye of the falcon which feeds by day, will differ from that of 
the owl which feeds by night: both will differ from that of the 
swan, which has to procure its food under water: but all are exactly 
adapted to their own peculiar spheres of action, all are capable of 
very astonishing sight. 
Again, the hearing of some is so subtle that they can detect their 
prey when hidden from view by this sense alone, and by the same 
power are ever on the alert for the approach of anenemy. As the 
eagle is the most renowned for powers of vision, so we may without 
hesitation pronounce the owls to possess a more acutesense of hearing 
