ts in this remarkable voyage. The mouth of the cave was northeast
of the Cataract home, and distant about a half mile, in a straight line.
The opening for the first six hundred feet, which had been charted by
them on the previous occasion, ran directly south, but from that point
it turned toward the southwest, and this now, in a measure, explained
the eagerness of the Professor to explore it, as he believed the cavern
led to a point near their home.

"There is no water in the opening," was the further information from
George, as they approached the contracted end of the chamber.

"Before we land let us see the other side of the chamber," was the
Professor's suggestion.

The boat was veered around to the left, and before they had proceeded
fifty feet it was apparent that a similar opening led out to the south,
and a dry floor was visible, like in the other outlet. The boat was
landed, and drawn up, two of the lamps taken out and the guns examined.
The opening led into a second chamber, which looked like a canopied
grotto of marble. Where they stood the chamber had the appearance of a
huge letter A, the side walls of which ran together in the distance, but
these walls were broken up by the most enchanting series of columns, and
delicate entablatures, and the outlines of the figures were like
blanched frescoes. It was such a weird and startling sight that the boys
could not repress their amazement.

After they had fully entered the chamber Harry's quick eye caught a
peculiar formation to the right, on a raised sort of platform, behind
which seemed to be a recess. He had noticed it because it contrasted so
strangely with the uniformly white glare of all the surrounding
surfaces. He quickly made his way across, and as he reached it, stepped
back in alarm.

"Come here, quickly; are those skulls and skeletons?"

The Professor did not need a second invitation. Scattered about on the
elevation were found four skulls, and the bones comprising the remains
of four human beings. The skulls were first arranged side by side, and
the Professor intently examined them.

"These are skulls of the Caucasian race, beyond a doubt. All are,
apparently, well formed and normal. But what is this?"

In the side of one skull was a perforation, with the bone fractured on
all sides of the orifice.

"Do you think it is a bullet wound?"

"It has that appearance. As there seems to be no corresponding hole in
any other portion of the skull, w