AN UNDERGROUND MYSTERY
“Say, have you fellows heard about that new vacuum tube?” asked Joe,
as the boys were tinkering with their set a day or so after the
incident of the wildcat.
“What about it?” the others asked, with interest.
“They say it’s the most powerful tube in the world,” Joe continued
enthusiastically. “Think of it—this tube is capable of supplying a
hundred kilowatts of oscillating high frequency energy to an
antenna.”
“Must be some hefty tube,” remarked Bob, rather absently. He was
trying to tune in on a station some distance away and there was
considerable interference.
“No, that’s just the beauty of it,” said Joe, still on the subject
of this wonder tube. “It’s small. Only weighs ten pounds.”
“I suppose that will have a big effect upon radio in general,” said
Herb.
“I’ll say so,” Joe returned. “Why, they say that two of these tubes
operated in parallel would do the work of a million dollars’ worth
of machinery in transatlantic communication.”
“Some tube, all right,” said Jimmy. “I bet it will bring the
inventor some hard cash, too.”
“He deserves it,” declared Joe. “Anyone who has brains enough to
invent a thing like that ought to be a millionaire.”
“Probably will be, too, before he gets through,” remarked Bob.
Jimmy sighed.
“Oh, for a few brains!” he murmured and Herb grinned happily.
“You said something that time, old timer,” he assured the despondent
Jimmy.
However, they wearied even of their radio sets after awhile and
decided to take a tramp in the woods, “just to pick up an appetite
for dinner.”
“Here’s hoping we don’t pick up a wildcat or two for good measure,”
said Joe.
“Oh, I don’t know,” replied Jimmy nonchalantly. “I’ve heard wildcat
steaks are very good eating.”
“So are bear steaks,” retorted Joe. “But I’m not particularly
anxious to meet the bear.”
“Let’s go over to the ranger station,” suggested Bob, “and see if
there’s any news. Then we might go around and see if our cave is
still there.”
The boys agreed, and a moment later they were being greeted
pleasantly by Mr. Bentley and one or two others. There had been no
fires of any account reported, the rangers assured them, and smiled
when the boys looked disappointed.
As usual, they stayed at the station longer than they had expected
to and when they came out they decided it was too late to go around
to their cave that afternoon.
“We’ll make a good early start in the morning and spend the day,”
decided Bob. “We can take some canned beans and rolls along so
Doughnuts won’t starve to death.”
“That reminds me that we’d better go around by way of the
crossroads,” said Herb. “Doughnuts ate up the last bit of jam last
night, and if we’re going on a picnic we’ve got to have jam.”
The boys agreed on the necessity, and so started to detour through
the woods in the direction of the little crossroads country store,
where a few things, they had discovered, could be bought.
But they were destined not to reach the store that afternoon. They
had never gone straight from the ranger station to the place, and so
the country through which they were passing was new to them.
They knew there was no possibility of their becoming lost, however,
for Mr. Bentley told them that if they followed straight along the
path they were now on they would come out right at the crossroads.
However, the way was long and as they had been climbing steadily
they finally sat down on the crest of a low mountain to regain their
breath and look at the scenery.
It was then that Joe discovered, half-way down the mountainside, a
curious gaping hole, half concealed by intertwining underbrush.
“Look!” he said. “That looks like a fair-sized cave to me.”
“Let’s go and have a closer look at it,” said Bob, curiously. “It’s
probably just a hole, but there may be something interesting about
it.”
Jimmy protested, for his short legs were weary, but Herb yanked him
to his feet and gave him a shove in the direction of the cave. Jimmy
had not been any too securely balanced in the first place, and
Herb’s shove had the effect of lifting him completely from his feet.
He fell, landed on his side and rolled down the steep side of the
mountain, turning over and over and grasping wildly at roots and
stones in his path.
So suddenly had it happened that for a moment the other boys only
stared. Then, as poor Jimmy went on rolling and finally disappeared
in the gaping mouth of the cave they gathered their wits and made
after him. Smothering their mirth, they half slid, half fell, down
the mountain side.
The ground was rough and stony and they were afraid that Jimmy might
be really hurt. Their fears were set at rest, however, when, upon
peering into the dark cavern, they found that Jimmy had regained his
feet and was glaring with a mixture of sheepishness and rage at
Herb.
“You big stiff!” he said, carefully feeling over his pudgy form to
make sure there were no bones broken, “next time you feel like
shoving a fellow, just look who you’re shoving, will you? I suppose
you think this was fun.”
“It was—for us,” retorted Herb, relieved to find he had not
seriously hurt his fat chum. “Stop glaring at me, Doughnuts,” he
added placatingly. “I didn’t mean to shove so hard, honest I
didn’t.”
“Well,” said Jimmy, somewhat mollified, “I suppose I’ll have to take
your word for it. Only don’t let it happen again, that’s all.”
“And now that we’re here,” said Bob, gazing about him with lively
interest at the walls of the cave into which they had literally
stumbled, “what do you say we look around a bit?”
“You bet,” agreed Joe, feeling in his pockets for matches. “From the
looks of things, if we’re going to do much exploring we’ll need
plenty of light.”
“I’ve got a new box of matches myself,” said Herb. “Any of the rest
of you fellows got any?”
It appeared that they all had, and Bob, feeling about on the floor
of the cave, found a stick that would serve them admirably as a
torch.
This he lighted with one of the precious matches and held it over
his head in an attempt to pierce the dark corners of the place.
“Probably ends a few feet farther on,” said Herb, as they carefully
made their way forward, groping along the damp walls of the cave.
“You go ahead with your light, Bob, and lead the way. It’s as dark
as pitch in this hole.”
But, contrary to Herb’s prediction, the cave did not end a few feet
further on. As a matter of fact, it seemed to widen as they went
forward and the boys began to feel a growing excitement.
“This is getting good,” chortled Bob, then stopped short as by the
light of his torch he discovered something new. “Say, fellows,” he
cried, in an excited voice, “here’s a tunnel—and, yes, there’s one
on the other side.”
“Better and better!” exulted Herb. “Which one of the tunnels shall
we explore first?”
“Why not take both?” asked Jimmy, who had completely recovered from
his ignominious tumble. “Two of us can go down one of them and the
other two can take the other.”
“Nothing doing,” said Bob, firmly. “We’re going to stick together on
this jaunt. We don’t want to take any chances of our matches giving
out and being left in the dark—not if I know it!”
When Bob spoke in this tone the other boys generally did as he said.
And this time was no exception. They tossed coins to determine which
of the diverging tunnels they would follow. This proved to be the
one to the right of them.
“This piece of stick is burning out,” said Bob, as they turned down
the dark passage. “Feel around and see if you can get any more, will
you, fellows? If we depend on matches they will be all burnt out
before we’ve seen half we want to see.”
They felt about the floor of the cave, which was damp and clammy to
the touch, and finally produced a couple of sticks which might be
made to do. These last were damp and rotten, but Bob finally
succeeded in lighting one.
“We’ll have to work fast, fellows,” he told them. “This isn’t going
to last long.”
And so they went ahead in real earnest, thrilled and fascinated by
the discovery that there was not one tunnel, or two, in this
remarkable cave, but a whole network of them, leading bewilderingly
one into another.
In their excitement the Radio Boys temporarily forgot that it was
much easier to get in than it would be to find their way out again.
All that seemed to matter at the time was to find to what point
these fascinating tunnels led. They had been using up matches at an
appalling rate of speed.
Then suddenly the torch in Bob’s hand flickered and went out
“More matches,” he called impatiently. “Herb, it’s your turn.”
A minute of dead silence while Herb fumbled wildly in his pockets.
Then faintly through the pitch blackness his voice came to them.
“I—haven’t any. I must have lost them.”