I don't much fancy this side of the island, somehow," said Jack, "but
we could pitch the tents on that little plateau up there and be
comfortable and have a good view up and down the river at the same
time."

And so it was arranged. Leaving the Wondership on the edge of the
clearing, they made camp on the flat ledge of sandy soil interspersed
with rocks that Jack had selected. From it they had a good view in
both directions. Above them was a small island, and below them the
river leaped and roared in a series of big rapids.

Their preparations for camping occupied all the afternoon. It was
supper time when they had finished and everything was shipshape and
comfortable. In the meantime Dick had wandered off with the rifle and
returned with four good-sized rabbits and three squirrels which Zeb
cooked into a savory stew.

They turned in early as they had all worked hard and were tired. Just
what time it was that he awakened, Jack did not know. But he thought
it was after midnight. Taking his watch he went to the door of the
tent to look at it in the moonlight, as he did not wish to arouse the
others by striking a light.

The moon flooded the island. Jack looked about him, enjoying the
beauty of the scene. The cliffs were great masses of black and white
and the rushing river gleamed like silver. He glanced toward the black
waste, on the edge of which they left the Wondership. The next instant
he uttered a startled exclamation. Above the bare patch of
dark-colored earth tall white figures were dancing, gleaming in the
moonlight.

Jack's heart gave a bound and he caught his breath for an instant.
Then he felt inclined to laugh at his own fears. What he had taken for
ghostly figures were columns of vapor writhing and twisting as they
steamed upward from the bare end of the island. What caused them, Jack
did not know. He noticed, too, that the whole patch of barren land
glowed with a strange phosphorescence like rotted wood.

Fascinated by the spectacle, he stood gazing at it. There was
something eerie about the dancing, pirouetting columns of vapor. They
looked like a party of ghosts dancing a quadrille. They twisted and
contorted and bowed and soared upward and sank again in a kind of
rhythm.

"Gracious, this is a spooky sort of place," thought Jack. "I wonder
what causes those wavering columns? Maybe some sort of hidden hot
springs like the one the professor fell into. I know one thing, I
don't like this island ove