Birds who sleep on the water--and they are numerous--are
always in danger of drifting to the shore, where lies their
greatest danger. In the Zoological Gardens of London it has
been discovered that ducks and other water-lovers have evolved
a way of avoiding this danger. Tucking one foot up among their
feathers, they keep the other in the water and gently paddle,
with the result that they revolve in circles and keep at a
safe distance from land, a kind of sleepwalking turned to good
account.--OLIVE THORNE MILLER, “The Bird Our Brother.”
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