bright eyes. The ducks understand crow and gull talk perfectly, and
trust largely to these friendly sentinels. The gulls scream and the
crows caw all day long, and not a duck takes his head from under his
wing; but the instant either crow or gull utters his danger note every
duck is in the air and headed straight off shore.

The constant watchfulness of black ducks is perhaps the most
remarkable thing about them. When feeding at night in some lonely
marsh, or hidden away by day deep in the heart of the swamps, they
never for a moment seem to lay aside their alertness, nor trust to
their hiding places alone for protection. Even when lying fast asleep
among the grasses with heads tucked under their wings, there is a
nervous vigilance in their very attitudes which suggests a sense of
danger. Generally one has to content himself with studying them
through a glass; but once I had a very good opportunity of watching
them close at hand, of outwitting them, as it were, at their own game
of hide-and-seek. It was in a grassy little pond, shut in by high
hills, on the open moors of Nantucket. The pond was in the middle of a
plain, perhaps a hundred yards from the nearest hill. No tree or rock
or bush offered any concealment to an enemy; the ducks could sleep
there as sure of detecting the approach of danger as if on the open
ocean.

One autumn day I passed the place and, looking cautiously over the top
of a hill, saw a single black duck swim out of the water-grass at the
edge of the pond. The fresh breeze in my face induced me to try to
creep down close to the edge of the pond, to see if it were possible
to surprise birds there, should I find any on my next hunting trip.
Just below me, at the foot of the hill, was a swampy run leading
toward the pond, with grass nearly a foot high growing along its edge.
I must reach that if possible.

After a few minutes of watching, the duck went into the grass again,
and I started to creep down the hill, keeping my eyes intently on the
pond. Halfway down, another duck appeared, and I dropped flat on the
hillside in plain sight. Of course the duck noticed the unusual
object. There was a commotion in the grass; heads came up here and
there. The next moment, to my great astonishment, fully fifty black
ducks were swimming about in the greatest uneasiness.

I lay very still and watched. Five minutes passed; then quite suddenly
all motion ceased in the pond; every duck sat with neck standing
str