manifest from the fact that the eagle can bear off a victim 
equalling himself in weight. Should he miscalculate, he can 
always drop his burden, or lessen its weight by eating part of 
it on the spot. Not so the osprey, or the sea-eagle, which 
have been known to plunge down and drive their talons 
into fishes too large to be raised. Unable to release their 
grip, death, by drowning, has inevitably followed. 
Sometimes the burden is a passenger, instead of a victim. 
One of the most striking of the coloured Plates in this volume 
is that of a woodcock carrying one of its nestlings to a distant 
feeding-place. This habit is well known. It is not often 
that the necessity arises, but there are occasions where 
suitable nesting and feeding grounds cannot be found together, 
or when, as during prolonged drought, the normal feeding 
area dries up. Then, instinctively, the parent will surmount 
the dangers of starvation for their offspring, by conveying 
them to a land of plenty, returning again to the shelter of 
the wood as soon as the meal is over. The weight of a 
newly-hatched nestling, it is true, could scarcely be called a 
“burden.” But they are carried about thus until they are 
strong enough to perform the journey for themselves. Thus, 
then, towards the end of the nursing period the weight to be 
carried is by no means a light one. 
But it was shown, long since, by direct experiment, that 
the area of a bird’s wing is considerably in excess of what is 
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