"Well, it's there somewhere!" declared Will.

"I see it now!" cried George. "It's under water!"

"Under water?" repeated Will.

"Yes, under water!" answered George. "If we don't get out of this hole before the pumps get to working we'll have to swim!"

Will turned his searchlight on the dip and saw that it was now full clear to the down dropping roof.

"I guess we'll have to swim," he agreed.

"That black water doesn't look good to me," George exclaimed with a little shudder. "It seems to me that I can see snakes and alligators wiggling in it from here. Looks worse to me than the swamps of the Everglades! And there was a quart of snakes to every pint of water down there!"

"But we got to swim just the same!" urged Will. "In half an hour from now the air in this chamber will be unbreathable. There is no vent at all, now that the water fills the dip, and the coal gas is naturally seeping in all the time."

"That's all right, too!" admitted George. "But I'm not going to jump into that black water until I have to. If a rope or something should twine around my legs while I was in there, I'd drop dead with fright!

Besides," he went on, "the chances are that Canfield will get the pumps going before long now."

The boys waited for a long half hour, during which time the water rose steadily. It seemed certain that the mine was about to be flooded throughout all the lower levels.

"Tommy and Sandy may have b.u.mped into just such a situation as this,"

Will said, as he pushed the boat from side to side in the hope of coming upon some exit from the place.

"Serves 'em good and right!" exclaimed George.

Will chuckled to himself and held a wet hand high up toward the roof of the chamber or pa.s.sage.

"There's a current of air here!" he said.

"Then we won't smother to death!" George grunted.

"And, look here," Will continued, as the boat b.u.mped into a pyramid of shale which had been thrown up to within a few inches of the roof, "some one has been building this hill of refuse and using it for a refuge!"

"It does look that way," George agreed. "That shows that at some time the water must have ascended to the very top of the wall. We may have to climb up there ourselves in order to keep from getting our clothing soaked in that ink down there!"

The water rose higher and higher in the pa.s.sage, and it seemed to the boys that by this time most of the lower gangways were entirely impa.s.sible.

"It doesn't seem to me that the water in this blooming old mine could rise any faster if the whole Mississippi river were turned into it!"

cried George in a tone of disgust. "If Canfield doesn't get his pumps going before long, he'll have a job here that'll take him all winter!"

"I presume he's doing the best he can," Will argued. "For all we know, the boilers as well as the electric motors may have been tampered with.

That would be just our luck!"

"I wonder what's become of that b.u.m detective?" asked George after a short silence. "We heard him rowing along in front of us one minute, and the next minute there wasn't a single sound to indicate that there was another boat in the mine."

"As soon as I get out of this," Will stated, "I'm going to make it my business to find out whether that detective is regularly employed on this case. He looks to me like a crook!"

It was dreary waiting there in the sealed-up chamber, and the boys found themselves dropping into long intervals of silence while they listened for the gurgle of the water which would indicate that the great pumps had been set in motion.

During one of those intervals of silence, they heard sounds which brought them to their feet in great excitement. Almost unable to believe his ears, Will turned to George with a question on his lips:

"Did you hear that?" he asked.

"Of course I did!"

"I did, too, but I thought I must be dreaming."

"No dream about that!" replied George. "That's the call of the Beaver Patrol!"

"And that means that Tommy and Sandy are not far away!"

"We heard the call of the Wolf Patrol not long ago," suggested George.

"I wonder if this blooming old mine is chock full of Boy Scouts of a.s.sorted sizes. There can't be too many here to please me!"

The boys returned the Beaver call but no answer came. At times they thought they heard whispers coming from the dark reaches of the cavern, but they were not quite certain.

"There may be real Beavers in here for all we know!" suggested Will.

"That's all you know about it!" chuckled George. "Beavers only operate in running water."

"Well, isn't that water out there running?" asked Will.

"No jokes now!" replied George. "I've got all I can endure now without standing for any of your alleged witticisms!"

While the boys sat in the boat, occasionally moving it from side to side, a shaft of light appeared directly above the point where the shale had been heaped up. It moved swiftly about for an instant and then dropped out of view. It was a moment before either boy spoke.

"That's some of Tommy's foolishness!" Will declared.

George repeated the Beaver call several times, but no answer came.

"That's a searchlight, anyway!" insisted Will. "And I don't believe these ginks in the mines have electric searchlights to lug around with them!"

Will unshipped an oar and struck the water with the flat of the blade several times, exerting his whole strength.

"Keep it up!" advised George. "That sounds exactly like a beaver's tail connecting with the surface of a stream!"

"Yes, keep it up!" cried a voice out of the darkness. "Keep it up, and perhaps some beaver'll come along and build a dam to get you out of that mess you're in! You're always getting into trouble, you two!"

"You've got your nerve with you!" exclaimed Will, half-angrily. "Here you go out in the night and get lost, and we come out after you, and the mine gets flooded, and we get tied up between the solid wall and a bend in the pa.s.sage, and then you blame us for getting into trouble!"

"Can you climb?" chuckled Tommy, throwing the rays of his searchlight on the boat. "If you can, just mount up on that pile of shale and work your way through the opening between the two levels. This might have been used as a sort of an air hole a few hundred years ago," he went on, "but I'll bet that not one out of a hundred of the miners of today know that there is an opening here!"

Leaving the boat, the boys mounted the pile of shale and were soon making their way up the rugged face of the shaft in the direction of the level, which ran along above the one now being flooded.

"Can you find your way out of this dump, now?" asked Will as the boys stood with their chums at the end of a long pa.s.sage.