he lay stretched out upon his back, panting heavily from weakness, it
seemed to him that the roar of the falling water had redoubled, and the
fancy came upon him that there was a tone of mocking triumph over his
helplessness. In fact, the exertion which he had been called upon to
make, the want of sleep, and possibly the exposure during many hours to
the burning sun, had slightly affected his brain, so that his wild
imagination conjured up non-existent dangers till all was blank, for he
sank into the deep sleep of exhaustion, and lay at last open-eyed,
wondering, and asking himself whether the foaming water that was
plunging down a few yards away was part of some dream, in which he was
lying in a fairy-like glen gazing at a rainbow, a little iris that
spanned in a bridge of beauty the sparkling water, coming and going as
the soft breeze rose and fell, while the sun sent shafts of light
through the dew-sprinkled leaves of the many shrubs and trees that
overhung the flowing water and nearly filled the glen.

Sleep still held him in its slackening grasp, and he lay motionless,
enjoying the pleasant sense of coolness and rest till his attention was
caught by a black-and-white bird which suddenly came into sight by
alighting upon a rock in the midst of the rushing stream.

It was one of many scattered here and there, and so nearly covered by
the water that every now and then, as the black-and-white bird hurried
here and there, its legs were nearly covered; but it seemed quite at
home, and hurried away, wading easily and seldom using its wings, till
all at once, as Pen watched, he saw the little creature take a step,
give its tail a flick, and disappear, not diving but regularly walking
into deep water, to reappear a few yards away, stepping on to another
rock, running here and there for a few moments, and again disappearing
in the most unaccountable way.

"It is all a dream," thought Pen. "Ducks dive, but no bird could walk
under water like that. Why, it's swimming and using its wings like a
fish's fins. I must be asleep."

At that moment the bird stepped on to another rock, to stand heel-deep;
and as it was passing out of sight with a quick fluttering of its wings,
which did not seem to be wetted in the least, Pen made an effort to
raise himself on his elbow, felt a dull, aching sensation of strain, and
lost sight of the object that had caught his attention. He found,
however, that it was no dream, for across the l