They traveled on for two days more, and saw nothing of the Fogers.  Sometimes they would pass through Mexican villages where they would stop to eat, and Tom would make inquiries about the ancient city of Poltec and the plain of the ruined temple.  In every case the Mexicans shook their heads.  They had never heard of it.  Long before this Tom had ascertained that neither Delazes nor any of his men knew the location of this plain nor had they ever heard of it.

“If there is such a place it must be far in—­very far in,” the contractor had said.  “You will never find it.”

“Oh, yes, I will,” declared Tom.

But when a week passed, and he was no nearer it than at first even Tom began to get a little doubtful.  They made inquiries at every place they stopped, of villagers, of town authorities, and even in some cases of the priests who obligingly went over their ancient church records for them.  But there was no trace of the temple plain, and of course none of the city of gold.

Peasants, journeying along the road, parties of travelers, and often little bodies of soldiers were asked about the ruined temple, but always the answer was the same.  They had never heard of it, nor of the head-hunters either.

“Well, I’m glad of the last,” said Mr. Damon, looking apprehensively around, while Eradicate of his head to see if it was still fast on his shoulders.

It was a weary search, and when two weeks had passed even Tom had to admit that it was not as easy as it had seemed at first.  As for the Mexicans, they kept on, spurred by the offer of good wages.  Delazes watched Tom narrowly, for a sign or hint of what the party was really after, but the young inventor and his friends guarded their secret well.

“But I’m not going to give up!” cried Tom.  “Our map may be wrong, and likely it is, but I’m sure we’re near the spot, and I’m going to keep on.  If we don’t get some hint of it in a few days, though, I’ll establish a camp, go up in the air and see what I can pick out from the balloon.”

“That’s the stuff!” cried Ned.  “It will be a relief from these rough ox carts.”

So for the next few days they doubled and redoubled on their trail, criss-crossing back and forth, ever hoping to get some trace of the temple, which was near the entrance to the city of gold.  In all that time nothing was seen of the Fogers.

“We’ll try the balloon to-morrow,” decided Tom, as they went into camp one night after a weary day.  Every one was tired enough to sleep soundly under the tents which were set up over the carts, in which beds were laid.  It must have been about midnight when Tom, who felt a bit chilly (for the nights were cool in spite of the heat of the day), got up to look at the campfire.  It was almost out so he went over to throw on some more logs.

As he did so he heard a noise as if something or somebody had leaped down out of a tree to the ground.  A moment later, before he could toss on the sticks he had caught up, Tom was aware of two eyes of greenish brightness staring at him in the glow of the dying fire, and not ten feet away.