ertained
they were carrying too many men; and also that they were to receive full
pay for the time they had engaged.

Of course they started to make objections, and the air was filled with
various excited exclamations; but Frank proved as firm as adamant, and
showed the automatic revolver sticking from his pocket all the while, a
fact that kept the two men from venturing to do more than shout.

Clutching their money they were pushed ashore by members of the crew,
who doubtless could give a pretty good guess as to what the whole thing
meant, since they had talked with Felipe.

"A good riddance of bad rubbish!" declared Andy, as the boat again
started up the river, leaving a pair of yelling natives behind, making
all sorts of furious gestures with both arms.

"Yes," pursued Frank, reflectively, "and if we wanted any more evidence
that we nipped a conspiracy to seize the vessel in the bud, there it is
in their anger at being paid for not working. Nothing like that was ever
known before down in this country, as Felipe says. And now, Andy, I
feel that we're another step nearer the carrying out of your great
task."

"Oh! I hope so," said the other, his face marked by an eagerness that
told of the one sole wish of his youthful heart.

CHAPTER XI.

OUT OF THE FRYING PAN INTO THE FIRE.

Frank took the first watch.

It was to begin about ten o'clock that night; for both of them had
remained on deck, talking, up to that hour. The night was so comfortable
after the hot day that they disliked going into the sleeping
quarters. These happened to face the deck, however, so that the vessel
was admirably suited to cruising in tropical regions.

"Every thing seems to be going on decently right now," remarked Andy,
yawning, as he prepared to have a few hours' sleep.

"That's so," returned his chum. "But while we've got some of the
faithful ones on duty, we mustn't forget that there may be other snakes
aboard. Enrique and the little shouter may not have been all the
sympathizers with the revolutionists. And not for a minute will we relax
our vigilance."

That was Frank's way; and just now Andy fully approved of it. His heart
was so set upon having a chance to use the monoplane in the endeavor to
discover that strange cliff-enclosed valley, where his father was
imprisoned, that he did not mean to take any chances of losing out
through over confidence.

So he packed off to his berth, while Frank prepared for three hou