lad, after they had been going a short time. "I know enough about Indians to be sure those fellows will follow us until they satisfy themselves who and what we are. They are up to some mischief, and they thought we were spying on them. Otherwise, I do not believe they would have tried to shoot us. Don't know as you could blame them much."

"I am inclined to agree with you, Master Tad. It will be good policy not to pay any attention to them if we discover any of them. Just go right along about our business as if we didn't see them at all."

"And you're not likely to," grinned Tad. "Where did you say they were going, Juan?"

"'Pache, go dance."

"He means they're bound for a pow-wow somewhere. That explains it," nodded the lad.

The rest of the day passed without incident. Not a sign of the Indians did the boys see. As a matter of fact, the roving redskins were as anxious to keep out of the sight of the Pony Riders as the boys were to have them do so.

The party enjoyed the trip over the mountains immensely; and, when, a few days later, they made camp in the foothills on the southern side of the Zuni range, the boys declared that they had never had a better time.

Professor Zepplin decided that they would remain in that camp for a couple of days, as he desired to make some scientific investigations and collect geological specimens. This suited the rest of the party, who were free to make as many side trips as they wished, into mountain fastnesses or over the plains to the south of them.

Early in the day the guide asked permission to go away for an hour or so. They noticed that he had been uneasy, apparently anxious to get away for some reason unknown to them.

"He's got something up his sleeve," decided Tad, eyeing Juan narrowly.

"You may go, but we shall expect you back in time for the noon meal," the Professor told him.

"Give me money," requested the guide.

"Certainly. Let me see, you have worked a week. I gave you five dollars when we started out. You were to have ten dollars a week while you were with us. That leaves five dollars due you," announced the Professor.

"Me work week. Me want ten dollars."

"But, my man, I've already paid you five dollars, which pays you for half of the week. Here is the five dollars for the other half. That's all I owe you. Do you understand?"

"Si señor. But Juan work one week," protested the guide.

"Let me show him," interrupted Tad. He drew ten marks in the sand with a stick, separating them into two groups of five. "Here are ten marks, Juan. We'll call them ten dollars. Understand?"

"Si."

"Well, here are the first five marks in the dirt that the Professor paid you. How many does that leave?"

"Five," gleamed the white teeth.

"Right. Go to the head of the class," interrupted Stacy.

"Chunky, you keep out of this. You'll mix him up."

"Guess somebody's mixed up already," retorted the fat boy.

"Five is right," continued Tad. "Five dollars is what we owe you. Is that clear now?"

"Si, señor. But I work one week. Juan earn ten dollar—"

"I'll tell you what to do," interjected Ned. "Start all over again. You begin work to-day; Juan, and we'll pay you ten dollars for every week from now on. You haven't worked for us before to-day, you know."

The lads laughed heartily, but Juan merely showed his teeth, protesting that he had earned ten dollars.

"Here," said Tad, thrusting a five dollar bill at him. "You take this. It's all we owe you. If you see any of your friends, you ask them how much we owe you. They'll tell you the Professor is right."

Juan took the money greedily, still protesting that they owed him ten dollars, because he had worked a week. Mounting his burro, he rode away; at once falling into the marvelous speed that he had shown them on the first day out.

The lads shouted with laughter as they saw burro and rider disappear among the foothills, both running for all they were worth, Juan uttering his shrill "yi-yi's," as he pedaled the ground.

That was the last they saw of the Mexican guide that day. The rest of the day was employed in games, trick riding, rope throwing and the like. Stacy found some horned frogs, which were of considerable interest to the boys. Chunky made the discovery that the frogs liked to have their backs scratched with a stick, and the frogs of the foothills probably never spent such a happy day in all their lives as Chunky and his stick provided for them that afternoon.

Late in the day, it dawned upon the boys that Juan was still absent. They consulted with the Professor about this, upon his return from a collecting trip along the foot of the mountains. But the Professor was sure Juan would be in in time for supper.

Such was not the case, however. After the meal had been finished Tad announced his intention of riding off in the direction Juan had gone, to see if the guide could not be found.

"I'll go with you," announced Stacy.

"All right; come along," said Tad, tightening his saddle girths. "We'll have a fine gallop."

"Be careful that you do not get lost, boys," warned the Professor.

"Can't get lost. All we have to do is to follow the foothills. We shall probably find Juan and his burro sound asleep on an ant-hill somewhere. He's positively the laziest human being I ever set eyes on."

"Better take along five dollars to bait him with," suggested Ned.

"I've got my stick," said Stacy. "I'll tickle the back of the burro and its rider, just as I did the frogs."

"You try that on the burro and he'll kick you into the middle of next week," warned Walter.

"Yes," laughed Tad. "Did you see him kick when Juan tossed a tomato can against his heels this morning? Kicked the can clear over a tree and out of sight."

"He'd make a good batter for the Chillicothe baseball team," suggested Chunky. "He'd be the only real batter in the nine. They could turn him loose on the umpire when they didn't need him on the diamond. Wouldn't it be funny to see some umpires kicked over the high board fence?"

"Come along if you are going with me."

Stacy swung into his saddle, and, galloping off, caught up with Tad, who was in a hurry to get back to camp before dark.

"Keep your eyes to the right, Chunky, and I'll look on the left. If you see anything that looks like a lazy Mexican and a lazy burro, just call out."

"I'll run over them, that's what I'll do," declared the fat boy. "Hello, there's a fellow on horseback."

"I see him."

The lads changed their course a little so as to head off the solitary horseman, who was loping along in something of a hurry.

"Howdy," greeted the lad.

"Evening, stranger. Where you hail from and where to?"

"We're in camp back here. I'm looking for our guide, a Mexican named Juan. He went away this morning and we haven't seen him since."

"And you won't so long as his money holds out," laughed the horseman.

"Then, you've seen him? Will you tell me where I may find him?"

"Sure thing, boy, but I reckon you'd better not be going any further?"

"Why not?"

"He's over yonder, gambling with some renegade Apaches."

"Apaches!" exclaimed the lads in one voice. "Those must be the same fellows we saw up in the range. But how do you suppose he knew they were over there?"

"He? Those Greasers know everything except what they ought to know—especially if there's any games of chance going on."

"Will you please tell me how we can reach the place? We want to make a very early start in the morning, and I don't like to take a chance of his not getting back in time."

"If ye're bound to go, keep right along the edge of the foothills. You can't miss the place. Better keep away if you don't want to be getting into a mix-up. There's going to be lively doings over there pretty soon," warned the stranger.

"How do you mean? I've seen Indians before. Guess they won't hurt us if they let Juan pow-wow with them."