A cormorant in a zoölogical garden, who wanted to catch some of the swallows skimming over the pond, sank his body till only his head was out, and held himself there perfectly still.
Birds who are hunted, as geese, have been known to save their lives in that way, by sinking their body under water, leaving in sight only the tip of the bill, which is so small it is not readily seen.
To do such things, birds must be able to make their bodies heavy when they choose, as well as light, which we know they are able to do by filling their air-sacs with air.
There are many things still to be found out about the powers of birds.
XXII
HIS BEAK AND TONGUE
How does a bird get along without a hand? He has to prepare food; to keep his feathers in order; to build the nest; to feed and take care of the young; and sometimes to fight other birds. How can all this be done without a hand?
