"Because there must be some infection in the grass there to have made so many of the cattle sicken and die."
"Maybe it was something else," suggested Nort.
"Well, maybe," assented the foreman. "It's about as mysterious as that underground river of yours. Had any more warnings, Bud?"
"No, I guess they're done with. And I believe it's a natural cause, and not due to any work of enemies, that accounts for the queer way our flume acts."
"Um!" spoke Slim musingly, and that was all he would say.
Borrowing horses from their friends, the boy ranchers next day made the trip over Snake Mountain and returned to camp, finding matters there in good shape. There was an abundance of water in the reservoir, and the pipe was flowing freely.
For more than a week nothing happened. The cattle at Flume Valley, including those of the boy ranchers, and the herd transferred from Square M to save it from the epidemic, were doing well, abundant grass and water being their portions.
There was no lack of hard work for the boys and their cowboy assistants, for it was not all easy sailing. Occasionally bunches of steers would stray, and have to be driven back by hard riding. There were night watches to be carried on, and another bunch of cattle was shipped away.
Bud, Dick and Nort hazed them over to the railroad, and on the trip a small-sized stampede gave them all they wanted to handle. But they were true sons of the west, and did not complain.
"Whew! That was hot, while it lasted!" exclaimed Bud, as he and cousins managed to get the stampeding animals quieted, after they had tried so hard to run off by themselves, in varying directions.