And so Paul stationed two boys in positions where they could watch for
every suspicious eddy, which was to be brought to his attention
immediately it was discovered.

An hour passed, and they were still moving steadily up the river. Paul,
in reply to many questions by his impatient comrades, announced that to
the best of his knowledge they ought to arrive at their destination an
hour and more before dark; which pacified the croakers, who had been
saying the chances were they would have to spend their first night on the
bank, short of the island by a mile or more.

"That's all right," Old Dan Tucker had remarked; "just so long as we get
ashore in time to build our cooking fire, it suits me."

Everything seemed to be moving along with clock-like regularity, the
boat breasting the current and throwing the spray in fine style, when
Jud gave a cry.

"Something's happened to the _Speedwell_!" he announced.

Of course every eye was instantly turned back, and they were just in time
to see something that announced the truth of Jud's assertion.

Andy Flinn stood up in the bow of the second boat, which no longer
chugged away as before, and he threw something out that splashed in
the water.

"It's their anchor!" cried Jud. "Either somebody's overboard, or else
their motor's broken down!"