And so it went on. Each time cattle were taken the spring was made to go dry, and the men thus fooled Uncle Fred and his cowboys. The bad men would hide the cattle and sell them to other men who did not know they were stolen.
So the secret of the spring might never have been discovered except for Laddie and Russ making that race to the bridge where they found the cowboy with the broken leg.
Sam Thurston became good after that, his leg healed, and he worked for Uncle Fred for a number of years. The bad men were sent to prison for a long time, and had no more chance to take cattle from any one.
"But aren't you going to dig down in the well we made, and see what is at the bottom of it?" asked Russ of his father, a day or so after the cattle had been got back and the men sent away.
"Yes, I think we shall," said Uncle Fred. "I'd like to know what that gurgle of water is."
So they dug and found out. But it had nothing to do with the secret of the spring, after all. It was only an old pipe, that had been laid some years before by a man that had formerly owned the ranch, before Uncle Fred bought it. The man laid a pipe from the overflow of the spring to a chicken coop, so the hens could get a drink. Then the pipe became covered over, and the man did not think to tell Uncle Fred about it when the ranch was sold.
But the secret of the spring was found out, and never after that did it go dry, and no more of Uncle Fred's cattle were taken.
"So it's a good thing we came out to see you, isn't it, Uncle Fred?" asked Laddie.
"I should say it was!" laughed his uncle.
"I'm going to make a riddle about it!" went on Laddie. "I don't just know what it's going to be, or what the answer is. But it will be a riddle."