"Thanks, Skinny," he said, pantingly.

"Don't mention it," replied the other. He shook free his rope, and the steer, now subdued, and tractable, rose to his feet and went back to the herd.

It needed every effort and attention on the part of the cowboys to keep the cattle from stampeding, but they managed to do it. The fire came on, halted at the burned strip, hesitated as if considering a leap across, and then divided, rolling down either side of the bare strip.

"That does the trick," said Mr. Carson. "I guess we've saved our stock."

"And we didn't need the plowed strip after all," Dave said, for, so far, the blaze had not approached within danger-distance of the herd.

"Well, it isn't over yet," said the ranch owner. "That fire still has plenty of ginger in it, and the wind may shift any minute. Dave, you worked well!"

"Oh, no better than any of the others."

"Yes you did! You worked well, and I shan't forget it But I'd like to know how this fire started. No cowman would be so careless with matches when he knows how dry it's been. And I don't believe lightning set it. I'd like to know how it started."

"So would I," said Dave, "and I think I'll investigate."

"How? Where?" asked the cattleman.