The natural supposition of the sentinel was that a large number of the
savages had gathered under the bank and were making ready for some
demonstration, which would soon take place.

It was not yet time to awaken the Professor and the natives. In fact,
the plucky New Englander half believed that with his repeating rifle he
would be able to beat off any approach from the other shore.

At this moment, he was amazed to see one of the savages do an
extraordinary thing.

Darting out from the wood behind him, he ran to the smouldering
camp-fire seized a brand that was covered with ashes, and circled it so
swiftly about his head that it was fanned into a roaring blaze.

While doing this, he stood apparently with one foot in the margin of
the Xingu, and evidently with not the slightest fear of the white
strangers within gun-shot. He not only swung the brand forward several
times, but reversed and spun it in the other direction, with a velocity
that made it look like a solid ring of fire.

Suddenly the truth flashed upon the bewildered sentinel: _the savage
was signaling to some friend or friends on the other bank_! That being
the case, it followed that the friend or friends were most
uncomfortably close to the camp of the white men.

And still Long failed to attach any importance to the unusual quantity
of logs and driftwood that was sweeping down the Xingu in front of him.

CHAPTER XII.

TO THE DEATH.

It was at this juncture that Jared Long, peering out from the shadow of
the wood, observed a larger log than any he had yet noticed, sweeping
by within a short distance of shore.

It was without any branches, except a few near the top, but there
seemed to be a number of big knots projecting from the upper side. He
counted seven and they were all of the same size. Furthermore, unless
he was mistaken, the huge tree, from some cause, was working closer to
land.

_Suddenly one of the knots moved_!

The sentinel uttered an exclamation, for the startling truth flashed
upon him with the quickness of lightning.

Each apparent knot was the head of a native!

With amazing coolness, the New Englander brought his Winchester to a
level, and _bang, bang, bang_, he shattered three of the knots in quick
succession.

He would not have stopped the frightful work even then, had not the
other targets disappeared.

Awaking to their danger, the warriors, dropped down so low in the water
that the log intervened betwe