r his note-books, and make
a new translation of the inscription on the golden plates. In a day or
so, refreshed and rested, he would prepare for another start.

"I'll find it this time, surely!" he would exclaim, as he marched off
up the mountain trail. "I have heard of a new valley, never before
visited by a white man, in which there are some old ruins. I'm sure
they must be those of Pelone."

But in a week or so he would come back, worn out and discouraged again.

"The ruins were only those of a native village," he would say. "No
trace of an ancient civilization there."

The professor took little or no interest in the tunnel, though he
expressed the hope that Tom and his friends would be successful. But
industrial pursuits had no charm for the scientist. He only lived to
find the hidden city which was to make him famous.

He heard the story of the queer shaft leading down into the bore under
the mountain, and, for a time, hoped that might be some clue to the
lost Pelone. But, after an examination, he decided it was but the shaft
to some ancient mine which had not panned out, and so had been
abandoned after having been fitted with a balanced rocky door, perhaps
for some heathen religious rite.

There seemed to be no further trouble among the Indian tunnel workers.
Those who had disappeared--who had, seemingly, gone willingly up the
knotted rope to hide themselves in the valley--kept on with their work.
If they told their fellows why and where they had gone, the others gave
no sign. The evil spirits of the tunnel had been exorcised, and there
was now peace, save for the blasts that were set off every so often.

Tom tried combination after combination, testing them inside and
outside the tunnel, always seeking for an explosive that would give a
slow, rending effect instead of a quick blow, the power of which was
soon lost. And at last he announced:

"I think I have it!"

"Have you? Good!" cried Job Titus.

"Yes," Tom went on, "I've got a mixture here that seems to give just
the effect I want. I tried it on some small pieces of rock, and now I
want to test it on some large chunks. Have you brought any down
lately?"

"Yes, we have some big slabs in there."

Some large pieces of the hard rock, which had been brought down in a
recent blast, were taken outside the tunnel, and in them one afternoon
Tom placed, in holes drilled to receive it, some of his new explosive.
The rocks were set some distance away from