en the workers had
disappeared Ned made his way to the underground room. There he found
torches burning, and a fire in the forge. The place was littered with
gas-pipe cut into small lengths, and the covers had been removed from the
tins of explosives.

It was clear that the bomb-makers had been at work there, and the boy
wondered at their nerve. He could account for their returning to their
employment there so soon after the place had been visited by hostile
interests only on the ground that they believed the secret service men and
the boys were being held at bay by others of the conspirators.

Wondering whether the boys who had gone on toward Gatun were safe, he
lighted the fuse of the bomb and hastened up the stairs and out into the
jungle. A few yards from the broken wall of the temple he met Jimmie, red
of face and laboring under great excitement. He turned the boy back with a
significant gesture toward the temple, and the two worked their way
through the thickets for some moments without finding time or breath for
explanations.

When at last they stopped for breath they found themselves about at the
point where they had parted from their chums. As they came into the
cleared space a flash lighted up the sky, flames went flickering,
seemingly, from horizon to horizon, and lifted to the zenith. Then came
the awful thunder of the explosion. The ground shook so that Jimmie went
tumbling on his face. After the first mighty explosion others came in
quick succession.

"That's the little ones," Jimmie cried, rolling over in the knee-deep
grass to clutch at Ned's knee. "Talk about your fourth of July."

As he spoke a slab of stone weighing at least twenty pounds came through
the air with a vicious whizz and struck a tree close to where the boy
lay.

"If we don't get out of here we'll get our blocks knocked off," Jimmie
said.

"The shower is over," Ned replied. "What were you running back for? If you
had not met me, if I had gone out another way, you might have been right
there when the explosion took place."

"Then I'd 'a' been sailin' around the moon by now," the boy grinned.

"Where is the captive?" demanded Ned.

"He went up in the air," replied Jimmie. "I had me eagle eyes on him one
second, and the next second he was gone. He didn't shout, or shoot, or
run, or do a consarned thing. He just leaked out. Where do you think he
went?"

"I think," Ned replied, "that you were looking back to see the explosion
an