“Quite possible,” replied the old man. “I will summon them and inquire.”

This he did. In response to his summons, half a dozen peons put in an appearance, but all denied any knowledge of the mule.

“He has probably gone down the river in the direction from which you came,” said Don Pablo, after the servants had gone back to their work. “That would be the most natural thing.”

“Quite likely,” was Donald’s reply. “We will

look for him in that direction. We are much obliged to you for your trouble.”

No hay de que,” meaning, there is no occasion for thanks, was the Mexican’s answer, and, without more ado, the boys took their departure.

“The old hypocrite,” exclaimed Donald, as soon as the boys were out of earshot. “I actually believe he found the mule himself, and knows where he is at this very minute.”

“I thought that myself,” commented Billie, “although I could understand very little of what was being said. But he was altogether too gracious.”

“What most aroused my suspicions,” said Donald, “was a side remark I heard him whisper to that big dark peon. I didn’t get the whole of it, but it was something about removing the livestock to another pasture. But he can’t fool me, if ever I get sight of old Bray, for he had the Keystone brand.”

The boys walked their horses slowly along, talking the matter over, undecided what to do next; but, as they at last emerged from behind a long row of cactus, which formed a hedge around one side of the hacienda, Billie uttered a sudden exclamation.