“I think we will put you on guard to-night, seeing that you are such a brave young man,” said the professor with a twinkle.

“On guard?”

“Yes.”

“Yes, that’s the idea.  Let him take the watch,” approved Rector.

“You forget that I’m a wounded man.  You forget I’ve been shot twice to-day.  Huh!  Some of you children take the trick.  I’ve got to take care of my health.”

“I guess if we expect to get any sleep we had better let some one else do it,” agreed Tad.  “Chunky will have us out on false alarms all night long.”

They were agreed upon this, and by common consent Butler was given the watch for the night.  The boys slept with their rifles beside them that night.

The night passed without incident, Tad Butler keeping a vigilant watch all during the dark hours of the night.  He had plenty of time to think matters over.  He realized that Dunk Tucker, the prisoner, had overheard all that had been said during their talk with Withem out on the plain.  Tad knew that if Dunk ever got into communication with his fellows it would go hard with the Pony Rider Boys.

Soon after daybreak, Tad awakened his fellows.  He already had a brisk fire going, but before lighting it, the lad had walked down to the edge of the canyon for a survey of the plain.  He saw a solitary horseman far out over the rolling plain.  After some study he made up his mind that the man was going away instead of coming toward them.

Breakfast finished the party packed their belongings and started out for their long ride to join the Rangers sometime late in the day.

About noon they made camp for dinner and a rest, not taking up their journey until about four o’clock in the afternoon.  Darkness overtook them, finding them still without sight or sound of the Spring where Withem said they would find the Rangers’ camp.  A consultation was held and it was decided to continue on until they picked up the party.

About half an hour after night had fallen, they were riding along when suddenly they were stopped by a stern command.

“Halt!  Hands up!  Every man of you is covered!”

“Oh, wow!” gasped Chunky.  “They’ve got us again.”

“Who are you?” demanded the voice.

“Who are you?” returned Tad boldly.

“I reckon my question gits the first answer, seeing as I’ve got the drop on you.”

Tad all at once realized that the sound of falling water was in the air.  With it came the thought that these must be the Rangers.

“We’re the Pony Rider Boys,” he said, speaking confidently.

“The which?”

He repeated his answer.

“Wait a minute.  Send for Joe,” said the man in a lower tone.  “You fellows stay just as you are if you don’t want some daylight let through you.”

“I—–­I wish we did have a little daylight,” stammered Chunky, which elicited a short laugh from his companions.  “Yeow!” bowled the fat boy as a figure appeared beside him and a pair of iron arms grasped his hands pulling him down, nearly unseating him.  “Yeow!  Let go!”