"And more by good luck than good management," a.s.serted d.i.c.k.

"How's that?" asked Slim, as they all started for the opening at the river end of the tunnel, where daylight dimly showed.

"Why, when we started in at the other side the stream was dry,"

explained Bud. "There wasn't a drop coming through the pipe into the reservoir, and we left, early this morning, to see what the trouble was. When we got half way through the stream suddenly began flowing, and there was a regular flood. Only that we found a ledge to climb up on, we'd been drowned!"

"As bad as that!" gasped Slim.

"Every bit!" d.i.c.k a.s.serted.

"But tell me," went on Bud, "did the water stop at the river end, Slim?

Was there any stoppage at the dam or pipe?"

"Nary a stop, Bud," Slim answered. "They told me, when I started in, that the water had been flowing all night, as usual, and they didn't see why you claimed there was none at your end."

"By Zip Foster! But there's something mighty strange here!" cried the boy rancher.

"You intimated good and plenty that time!" declared Slim as he and the boys reached the river end of the tunnel, where the intake pipe took the water from the Pocut stream, delivering it to the tunnel.

"But here's a queer part of it," went on d.i.c.k, as they joined the other cowboys who were preparing to follow Slim in, and search for the Diamond X lads. "No such body of water, as so nearly overwhelmed us, ever came through this pipe," and he pointed to the one that tapped the dammed-up water of the river.

"That's right!" agreed Bud. "This thing gets worse and worse! We'll never get to the bottom of this mystery!"

"You're right!" declared one of the cowboys. "When you're dealing with them underground water-courses you never know what you're up against.

The old Indians and Spaniards who lived here hundreds of years ago had their own troubles, and maybe they wished them same troubles on to you."

"What you mean?" asked Slim. "That's all bosh!"

"Bosh nothin'!" declared another. "You read history an' you'll get lots of cases where streams showed up, and then vanished under mountains, more than once."

"A heap sight you know about _hist'ry_!" laughed Slim in good-natured raillery.

"Well, this is sure queer, anyhow!" declared Bud. "Is there any history of the stream that waters our valley?" he asked the cowboy who had made the a.s.sertion.

"Not your particular one," was the answer, "but there's lots of just such cases mentioned--hidden water-courses and all that."

"Well, there's something wrong," agreed Bud, "and I believe there must be some place along the tunnel where our water shunts itself off at times, and turns itself on again. We were looking for just such a place."

"And you didn't find it?" asked Slim.

"Nary a find!" a.s.serted Bud.

"But we aren't going to give up, just on that account!" said Nort.

"Bet you not!" added his brother. "We'll try it again, and take a canoe with us, so if the dry water-course suddenly turns wet, we can paddle along it."

"Well, it seems to be all right now," spoke Slim. "And you'd better 'phone your father that you're all right, Bud. He'll be anxious to hear."

And after Mr. Merkel had been a.s.sured, over the wire, of the safe transit of his son and nephews through the tunnel, the boys' camp was called up, to let Old Billee and the others know that no accident had happened.

"Gosh! I'm glad to hear that!" said the veteran cowboy over the wire.

"When we see that there water come gushin' out, we thought sure you was goners, Bud!"

"Then the water is running again?" Bud asked.

"Absolutely!" declared Billee. "You comin' back here?"

"Sure! But _over_ the mountain--not _under_ it."

Bud and his boy rancher chums remained that night at the store settlement near the dam, getting beds in what pa.s.sed for a hotel. It was too late to secure horses and ride over Snake Mountain trail back to Flume Valley.

While thus having a night of leisure, and seeing such sights as were to be viewed in the little town, Bud and his chums discussed the queer situation of the mysteriously disappearing and reappearing water. But, talk as they did, and venture opinions as they and their cowboy friends did, no one could hit on a solution.

"We'll just have to make another and more careful inspection," declared Nort.

"That's what!" agreed Bud.

They learned from Slim that the situation regarding the cattle epidemic at Square M ranch was not much better. All stock which had not been exposed to the infection had been removed, either to Diamond X, Triangle B or Flume Valley, and the infected steers remaining there were being treated by a veterinarian whom Mr. Merkel had engaged.

"But they're slowly dying off," Slim reported. "And I don't believe Square M ranch will ever be safe to use again."

"Why not?" asked Bud.

"Because there must be some infection in the gra.s.s there to have made so many of the cattle sicken and die."

"Maybe it was something else," suggested Nort.

"Well, maybe," a.s.sented 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 gra.s.s and water being their portions.

There was no lack of hard work for the boys and their cowboy a.s.sistants, 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, d.i.c.k 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.

"Yes, a thing like that gives you an appet.i.te," remarked d.i.c.k.

"As if _you_ ever needed any stimulant!" laughed Nort. "I never saw the time yet when you had to be offered an inducement to sit up to grub!"

"You either!" retorted the stout lad. "But, speaking of grub, when do we eat, Bud?"