ef conversed rapidly for a moment and
then the former, turning to Tom, said:

"Men go git cinchona bark now. Plenty get for him," and he pointed to
Mr. Damon. "They no like stay in village. T'ink yo' got lightning in
yo' pocket," and he pointed to the electric rifle.

"Oh, I see!" laughed Tom. "They think I'm a sort of wizard. Well, so I
am. Tell them if they don't get lots of quinine bark I'll have to stay
here until all the mad dogs are shot."

The interpreter translated, and when the chief had ceased replying, Tom
and the others were told:

"Plenty bark git. Plenty much. Yo' go away with yo' lightning. All
right now."

"Well, it's a good thing I keeled over that dog," Tom said. "It was the
best object lesson I could give them."

And from then on there was no more trouble in this district about
getting a supply of the medicinal bark.

A week passed and Professor Bumper was no nearer finding the lost city
than he had been at first. Reluctantly, he returned to the tunnel camp
to get more provisions.

"And then I'll start out again," he said.

"We'll go with you some other time," promised Tom. "But now I expect
I'll have to get another blast ready."

He found the debris brought down by the second one all removed, and in
a few days, preparations for exploding more of the powder were under
way.

Many holes had been drilled in the face of the cliff of hard rock, and
the charges tamped in. Electric wires connected them, and they were run
out to the tunnel mouth where the switch was located.

This was done late one afternoon, and it was planned to set off the
blast at the close of the working day, to allow all night for the fumes
to be blown away by the current of air in the tunnel.

"Get the men out, Tim," said Tom, when all was ready.

"All right, sor," was the answer, and the Irish foreman went back
toward the far end of the bore to tell the last shift of laborers to
come out so the blast could be set off.

But in a little while Tim came running back with a queer look on his
face.

"What's the matter?" asked Tom. "Why didn't you bring the men with you?"

"Because, sor, they're not there!"

"Not in the tunnel? Why, they were working there a little while ago,
when I made the last connection!"

"I know they were, but they've disappeared."

"Disappeared?"

"Yis sir. There's no way out except at this end an' you didn't see thim
come out: did you?"

"Then they've disappeared! That's all there is to