not far away and covered with debris
as he had been.

He set the little light on a rock, leaving the switch on, and by the
intense but limited glow, he set to work to free his companions. Blake's
head was bleeding from the cut of a sharp rock, but he, like Joe and
Charlie, had fallen in such a way, or rather, the cave-in had taken
place in such a manner, that their heads and faces were comparatively
free from dirt, else they would have been smothered.

Joe worked feverishly to free his chums and at length succeeded in
freeing his assistant, who, of the two, was less covered by the debris.
Charlie opened his eyes and looked about him, asking:

"What happened? Where am I?"

"Don't stop to ask questions now," directed Joe. "Help me with Blake.
I'm afraid he's hurt!"

The two together got their chum cleared of the debris finally, and then
Joe, taking a flask of cold coffee from his pocket, gave his now
half-unconscious chum some to drink. This served further to rouse Blake,
and it was soon found, aside from a painful cut on the head, that he was
uninjured except for bruises, such as they all had.

"But what happened?" asked Charlie, as they sat down to rest on some
rocks and took turns finishing Joe's limited supply of coffee.

"The tunnel caved in on us after a big explosion of some kind," Joe
said. "I guess we're going to have trouble getting out, too."

"Let's have a look," suggested Blake. "We can't stay in here much longer
or more of the roof and sides may cave in. Can we get out?"

"I haven't looked," answered Joe. "I wanted to get the dirt off you
fellows. I'm afraid we're caught, though."

And they were. An examination, made with the pocket lights, showed them
that the way back was blocked by a mass of rock and earth and that no
progress ahead could be made for the same reason.

"I guess we'll have to dig our way out," said Joe.

"What with?" asked Charlie.

"Some of the broken boards that held up the tunnel," was the answer, and
Joe pointed to pieces of timber that had been splintered and shattered
by the cave-in.

"Yes, it's the only way out," agreed Blake, who, now that his cut had
been bound up with bandages from the first-aid kits the boys carried,
felt better. "We'll have to dig out." And after a short rest they began
this work.

A terrible fear was upon them, a fear greater than that caused by their
capture by the Germans with the possibility of being shot as spies. It
was the fear of a ho