each," proposed the
Englishman; "there is no telling what we may find; we may run on
something that has drifted ashore from some wrecked ship."

Johnston consented. They had encompassed the entire island, which was
oval in shape, and were about to ascend to the rock to put fresh fuel
on the fire before lying down to sleep for the night, when Thorndyke
noticed a road that had evidently been worn in the rock by human
footsteps.

"Made by feet," he said, bending down and looking closely at the rock
and raking up a handful of white sand, "but whether the feet of savage
or civilized mortal I can't make out."

Johnston was a few yards ahead of him and stooped to pick up something
glittering in the moonlight. It was a tap from the heel of a shoe and
was of solid silver.

"Civilized," he said, holding it out to his companion; "and of the very
highest order of civilization. Whoever heard of people rich enough to
wear silver heel-taps."

"Are you sure it is silver?" asked the Englishman, examining it closely.

"Pure and unalloyed; see how the stone has cut into it, and feel its
weight."

"You are right, I believe," returned Thorndyke, as Johnston put the
strange trophy into his pocket-book, and the two adventurers paused a
moment and looked mutely into each other's eyes.

"We haven't the faintest idea of where we are," said Johnston, his tone
showing that he was becoming more despondent. "We don't know how long we
were unconscious in the balloon, nor where we were taken in the storm.
We may now be in the very centre of the North Polar sea--this knob may
be the very pivot on which this end of the earth revolves."

The Englishman laughed. "No danger; the sun is too natural. From the
poles it would look different."

"I don't mean the old sun that you read so much about, and that they
make so much racket over at home, but another of which we are the
original discoverer--a sun that isn't in old Sol's beat at all, but one
that revolves round the earth from north to south and dips in once a day
at the north and the south poles. See?"

The Englishman laughed heartily and slapped his friend on the shoulder.

"I think we are somewhere in the Atlantic; but your finding that
heel-tap does puzzle me."

"We are going to have an adventure, beside which all others of our lives
will pale into insignificance. I feel it in my bones. See how evenly
this road has been worn and it is leading toward the centre of the
island."

In a f