addy, with a chuckle. "Everybody does. I did
first time. Well, they won't, so you needn't be afeared o' that. Nex'
thing as kept you awake was that you thought a great boa-constructor
might be up in the tree and come crawling down into the boat."

"Shaddy, are you a witch?" cried Rob.

"Not as I knows on, my lad."

"Then how did you know that?"

"Human natur', lad. Every one thinks just like that. Next you began
thinking that them pretty creeturs you can hear singing like great cats
would swim across and attack us, or some great splashing fish shove his
head over the side to take a bite at one of us. Didn't you?"

Rob was silent for a few moments, and then said,--

"Well, I did think something of the kind."

"Of course you did. It is your nature to think like that, but you may
make your mind easy, for there's only one thing likely to attack you out
here."

"What's that?" whispered Rob--"Indians who will swim out from the
shore?"

"No, wild creeturs who will fly--skeeters, lad, skeeters."

"Oh," said Rob, with a little laugh, "they've been busy enough already,
two or three of them. But what's that?"

He grasped Shaddy's arm, for at that moment there was a plunge in the
river not very far-away in the darkness from where they were moored, and
then silence.

"Dunno yet," said Shaddy in a whisper. "Listen."

Rob needed no telling, for his every nerve was on the strain. There
came a peculiar grunting sound, very unlike any noise that might have
been made by a swimming Indian, and Shaddy said quietly,--

"Water hog. Carpincho they calls 'em; big kind of porky, beavery,
ottery, ratty sort of thing; and not bad eating."

Rob pressed his arm again as a sharp, piercing howl came from far-away
over the river, here about four or five hundred yards across.

"That's a lion," said Shaddy quietly. "Strikes me they shout like that
to scare the deer and things they live on into making a rush, and then
they're down upon 'em like a cat upon a mouse."

"Lion? You mean a puma."

"Means a South American lion, my lad."

"There it is again," whispered Rob in an awe-stricken voice, "only it's
a deeper tone, and sounds more savage."

"That's just what it is," said Shaddy, "ever so much more savage. That
wasn't a lion; that was a tiger--well, jagger, as some calls 'em. Deal
fiercer beasts than the lions."

The cries were repeated and answered from a distance, while many other
strange noises arose, to which