here it led to.

Drawing a long breath of surprise and satisfaction, he ceased rowing,
and, as the boat came to a stand-still on the glassy surface of this
subterranean sea, he uttered an exclamation of wonder, and looked around
him in a maze of doubt and admiration.

The cool, grotto-like atmosphere and dim, half-twilight contrasted
pleasantly with the heat and glare outside, though the silence was
something oppressive, and different from any he had ever before known.

No sound of wave or sigh of wind or howl of tempest seemed ever to have
been heard here. The water along the edges of the rocks was absolutely
without motion, and the light from either extremity of the cave--as one
might call it--nearly lost itself before it reached the vaulted centre.

Frank shouted loudly, and in answer the rocks sent back only the
faintest and most weirdly far-away echoes.

When Frank had somewhat recovered from his astonishment, and his eyes
had become accustomed to the dim light, he found the cay, or channel, to
be some fifty yards in extent, cut through the soft, porous rock by the
action of the water, that for ages and ages of time had beaten against
its gradually-yielding base, until it had made for itself a passage such
as man, with all his marvelous ingenuity, could never have fashioned.

Frank rowed the entire length of the cay--as the Bay Islanders call
these little wave-made inlets--coming out on the opposite side to that
which he had entered; and then, as it was getting late, he returned
home, as the brave-hearted boy termed the spot where he had pitched his
tent and stored his provisions.

Apart from finding the channel, he had made no discovery worth
mentioning. With the exception of a few sea-birds, he saw no living
creature, great or small; but this he did not much mind, for he hoped a
sail would come his way soon, and solitude was no new thing to him. So
he ate his supper with hearty relish, and, when it was dark, clambered
into his hammock and fell peacefully asleep.

CHAPTER XIII.

A CHANGE OF PLANS.

The morning of the tenth day of his residence upon the island Frank
rowed around to the grotto--as he called his new-found giant's
causeway--taking with him his fishing-tackle and a substantial luncheon
of bread and cheese and dried beef.

Fish of various kinds abounded in the quiet waters of the inlet, and in
an hour he had caught as many as he wished to carry "home."

He had seen no sharks anywhere nea