ick asked.

"Wait a minute," counseled Bud. "Let's see if we can reason this out."
He paused to give it thought. "The way this stream is running now," he
resumed, "wouldn't put any water into our reservoir, would it?"

"No," answered Yellin' Kid, and for once his voice was softened. "Th'
water is all being shunted down this passage--where Nort fell."

"But," resumed Bud, "this passage has always been here. We didn't see
it before, as we walked on the other side of the main channel. Then if
this side channel has always been here, and we managed to get water
through our pipe when it was here, it stands to reason that it must
fill in time, enabling the water to run along here," and he indicated
the regular channel that extended back of them out toward Flume Valley.

"That's so!" cried Old Billee. "There's an end, or a bottom, t' this
channel somewhere, and poor Nort can't be carried all the way through
th' earth."

"But--but," faltered Dick. "It may be too late to save him when this
side passage fills up."

"What I was going to propose," went on Bud, "is that we see if we can't
follow along this newly-discovered side passage, as we have been
following the main bed of the underground river."

He paused to let his companions visualize this suggestion.

"Do you think that would be safe?" asked Old Billee. "I mean," he
added quickly, "will that be th' safest way t' try an' save Nort? I
won't back down on anything--I guess you know that--but I was just
wondering if there was some other way."

"There might be," said Bud. "We could go along on the left side of the
stream, and see if there is a crossing place farther on. We saw some
narrow places when we were here before, but it's a question how much
water they'd have in them now."

"Oh, but can't we do something?" cried Dick, now almost sobbing, though
he was making a brave effort to conquer himself. "Oh, Nort! Nort!
Where are you?" he cried frenziedly.

But again only the echoes answered.

"Come on!" cried Old Billee suddenly. "We'll try this way. We've got
t' do something!"

"Leave our packs here," suggested Yellin' Kid, and again his voice was
low, as if in deference to Dick's feelings. "We can put 'em up on that
ledge," he added, indicating a small one on their side of the
underground stream. "The water doesn't appear to have been up there in
years. If we leave our things here we'll be better able to help
Nort--if we find him," he added in a