The man shook his head, but a quick look pa.s.sed between him and his employer.

"Oh, I guess we'll let Rad drive," insisted Tom calmly, "it will remind him of his mule Boomerang that he left behind."

"As the senor will," Delazes had replied with a shrug of his shoulders, and he turned away. So it was that Tom, Ned and Mr.

Damon, in their own cart, piloted by the colored man, were in the rear of the little cavalcade.

"Have you any idea where you are going, Tom?" asked Ned, after they had reached the shade, when it was not such a task to talk.

"Oh, I have a good general idea," replied the young inventor. "I've studied the map Mr. Illingway sent, and according to that the city of--well, you know the place we're looking for--lies somewhere between Tampico and Zacatecas, and which the plain of the ruined temple which used to be near the ancient city of Poltec, is about a hundred and fifty miles north of the city of Mexico. So I'm heading for there, as near as I can tell. We ought to fetch it in about a week at this rate."

"And what are we to do when we get there?" inquired Mr. Damon. "If we keep on to that place where the images are to be found, with this rascally crew of Mexicans, there won't be much gold for us." He had spoken in low tones, though the nearest Mexican cart was some distance ahead.

"I don't intend to take them all the way with us," said Tom. "When I think we are somewhere near the temple plain I'm going to make the Mexicans go into camp. Then we'll put the balloon together and we four will go off in that. When we find what we're looking for we'll go back, pick up the Mexicans, and make for the coast."

"If the head-hunters let us," put in Ned grimly.

"Bless my nail file! There you go again!" cried Mr. Damon.

"Positively, Ned, you get on my nerves."

"Yais, Ma.s.sa Ned, an' _I_ jest wish yo' wouldn't mention dem head gen'men no mo'," added Eradicate. "I can't drive straight when I hears yo' say dem words, an' goodness knows dese oxes is wusser t'

drive dan my mule Boomerang."

"All right I'll keep still," agreed Ned, and then he and Tom, together with Mr. Damon, studied the map, trying to decide whether or not they were on the proper trail.

They made a good distance that day, and went into camp that night near the foot of some low hills.

"It will be cooler traveling to-morrow," said Tom. "We will be up higher, and though we'll have to go slower on account of the up grade, it will be better for all of us."

They found the trail quite difficult the next day, as there were several big hills to climb. It was toward evening, and they were looking for a good place to camp for the night, when Delazes, who was riding in the first cart, was observed to jump down and hasten to the rear.

"I wonder what he wants?" spoke Tom, as he noted the approaching figure.

"Probably he's going to suggest that we take a few days' vacation,"

ventured Ned. "He doesn't like work."

"Senor," began Delazes addressing Tom, who called to Eradicate to bring his oxen to a halt, "are you aware that we are being followed?"

"Followed? What do you mean?" cried the young inventor, looking quickly around.

"Bless my watch chain!" gasped Mr. Damon. "Followed? By whom?" He, too, looked around, as did Ned, but the path behind them was deserted.

"When last we doubled on our own trail, to make the ascent of the big hill a little easier," on the Mexican, "I saw, on the road below us two ox carts, such as are hired out to prospectors or relic seekers like yourself. At first I thought nothing of it. That was early this morning. When we stopped for dinner, once more having to double, I had another view of the trail, I saw the same two carts.

And now, when we are about to camp, the same two carts are there."

He pointed below, for the caravan was on quite an elevation now, and down on the faint trail, which was in plain view, for it wound up the mountain like a corkscrew, were two ox carts, moving slowly along.

"They are the same ones," went on Delazes, "and they have been following us all day--perhaps longer--though this is the first I have noted them."

"Followed!" murmured Tom. "I wonder--" From his valise he took a small but powerful telescope. In the fast-fading light he focused it on the two ox carts. The next moment he uttered an exclamation of anger and dismay.

"Who is it?" asked Ned, though he was almost sure what the answer would be.

"Andy Foger and his father!" cried Tom. "I might have known they'd follow us--to learn--" and then he stopped, for Senor Delazes was regarding him curiously.

CHAPTER XIV

A WEARY SEARCH

"Are you sure it's them?" asked Ned.

"Bless my toothpick!" cried Mr. Damon. "It isn't possible, Tom?"

"Yes, it is," said the young inventor. "It's the Fogers all right.

Take a look for yourself, Ned."

The other lad did, and confirmed his chum's news, and then Mr. Damon also made sure, by using the gla.s.s.

"No doubt of it," the odd man said. "But what are you going to do, Tom?"

Our hero thought for a moment. Then, once more, he looked steadfastly through the gla.s.s at the other carts. The occupants of them did not appear to know that they were under observation, and at that distance they could not have made out our friends without a telescope. Tom ascertained that the Fogers were not using one.

"Has Senor Swift any orders?" asked Delazes. "Who are these Fogers?

Enemies of yours I take it. Why should they follow you merely to find a ruined city, that the ruins and relics may be studied?"

"Here are the orders," spoke Tom, a bit sharply, not answering the question. "We'll camp and have supper, and then we'll go on and make all the distance we can after dark."

"What, travel at night?" cried the Mexican, as if in horror at the suggestion.

"Yes; why not?" asked Tom calmly. "They can't see us after dark, and if we can strike off on another trail we may throw them off our track. Surely we'll travel after supper."

"But it will be night--dark--we never work after dark," protested Delazes.

"You're going to this time," declared Tom grimly.

"But the oxen--they are not used to it."

"Nothing like getting used to a thing," went on the young inventor.

"They won't mind after a rest and a good feed. Besides, there is a moon to-night, and it will be plenty light enough. Tell the men, Senor Delazes."

"But they will protest. It is unheard of, and--"

"Send them to me," said Tom quickly. "There'll be double pay for night work. Send them to me."

"Ah, that is good. Senor Swift. Double pay! I think the men will not object," and with a greedy look in his black eyes the Mexican contractor hastened to tell his men of the change of plans.