"Tad's gone in, too," shouted Walter excitedly, as their ears caught
a second splash. It was more clean cut than had been Stacy's dive,
and might have passed unnoticed had they not known the meaning of
the sound.

Ned Rector stood as if dazed. He knew that somehow he had
thoughtlessly plunged his companions into dire peril.

"Wha--what is it?" he stammered.

"They're in the river! Don't you understand?" answered Walter
sharply, moving forward as if to follow over the bank in an effort
to rescue his companion.

"Keep back!" commanded the Professor. "You'll all drown if you go
over that bank."

The Professor, with more presence of mind than the others, had
sprung up and rushed for the camp-fire, from which he snatched a
burning ember.

At any other time the sight of his long, gaunt figure, clad in a
full suit of pink pajamas, dashing madly about the camp, would have
excited the lads to uproarious merriment. But laughter was far from
their thoughts at that moment.

"Use your eyes! Do you see him?" demanded Professor Zepplin, peering
down anxiously into the shadows.

"No. Oh, Tad!" shouted Ned. There was no reply to the boy's