t with a heavy
heart. At the same moment his attention was attracted by a sharp
squeaking, and, to his dismay, he made out a confused mass of
something in active motion about the precious biscuit that he had left
beside his fireplace. With a loud cry he sprang in that direction,
only to stumble and fall over a small pile of what he took to be rocks
that lay in his path.

Without waiting to regain his feet, he flung several of these at the
animals that had discovered and were devouring his hardtack. A louder
squeak than before showed that at least one of his missiles had taken
effect, and then there was a scampering away of tiny feet. When he
reached the scene of destruction his only biscuit was half eaten,
while beside it lay a huge rat that had been killed by one of his
shots.

"With plenty of rats and plenty of rocks I need not starve, at any
rate," he remarked, grimly. "The idea of eating rats is horrid, of
course, but I don't know why it should be. Certainly many persons have
eaten them, and in an emergency I don't know why I should be any more
squeamish than others.

"What heavy rocks those were, though, and what sharp edges they had! I
expect it will be a good idea to collect a few, and have them ready
for my next rat-hunt."

With this Peveril returned to the pile over which he had stumbled, and
to his amazement found it to be composed of hammers and hatchets,
chisels, knives, and other tools that he was unable to name, all of
quaint shape, and all made of tempered copper. In an instant the
nature of his prison became clear. He was in a prehistoric
copper-mine, opened and worked thousands of years ago by a people so
ancient that even tradition has nought to say concerning them.

The knowledge thus thrust upon him filled the young man with awe, and
he glanced nervously about him, as though expecting to see the ghosts
of long-ago delvers advancing from the inner gloom. The thought that
he was probably the first human being to set foot on that rocky
platform since the prehistoric workmen had flung down their tools on
it for the last time was overpowering.

At the same time, if this were indeed a mine, it must also be a tomb,
for it was not likely to have any exit save the unscalable shaft
glimmering hopelessly above him. Here, then, was the end of all his
hopes, for of what use were strength and courage in a place where
neither could be made available?

But hold! Where had the rats come from? Certainly not