I am not mistaken, old Malmsworth has holed
up in that very same rift where we caught him at his dirty business
seventeen years ago. He's as mad as a Martian; you can lay to that. He'd
have to be."

The rift, when they arrived at its upper reaches, was cool and shadowy.
In its depths nothing sparkled. It was ordinary limestone. The walls
were covered with a dull yellow moss, except for great, raw wounds where
it had been torn off.

"That's Malmsworth's work," Captain DeCastros said. "In seventeen years,
Mr. Wordsley, one will consume a lot of moss, I daresay. Shall we
descend?"

The rift had reached its depth quite gradually, so that Mr. Wordsley
scarcely realized that they were going down until the surface glare was
suddenly gone, and the green-walled gloom surrounded them. It might have
been a pleasant place, but Mr. Wordsley did not like it.

Captain DeCastros was taking his time now, resting frequently. There was
not the slightest chance of Malmsworth's getting away, for at the other
end of the rift lay the cave and the abyss containing, at least, one
ghost of Malmsworth's terrible past.

But though it might seem drab after the plateau and the plain, the rift
had its points of interest. Along the walls, everywhere, as high as a
tall man might reach, the moss had been torn or scraped from the
surface. There was no second growth.

* * * * *

Every quarter of a mile or so they came upon the former campsites of the
castaway, each marked by a flat-topped cairn of small stones three or
four feet in height. DeCastros was at a loss to explain this. Mr.
Wordsley supposed that it was one of the marks of a diseased mind.

Not that he actually understood the workings of a diseased mind.
Privately, he suspected that DeCastros was a little mad. Certainly he
was subject to violent, unreasonable tempers which could not be
explained. The unfortunate strain might have cropped up more strongly in
his brother.

Might not these walls have rung with lunatic screams after months and
years of hollow-eyed watching for the ship that never came? It might
have been different, of course, had Malmsworth been able to appreciate
the aesthetic values of life, as Mr. Wordsley did. But doubtless these
lovely miles and miles of crystalline oceans had been but a desert to
the castaway.

Eventually the rift widened a little, and they came to a dead end,
beyond which lay the cave. It must have been formed ages