The way grew rougher with every yard they traversed. How Spanish Joe had come dashing down over this ground at headlong speed without breaking his neck was a puzzle.
Frank was feeling his way along carefully when he heard Bob call his name. The rattle of falling shale at the same time gave him a pretty strong suspicion as to what had happened.
"Hello! what's the matter Bob?" he cried.
"I slipped, and fell over the edge of some sort of place here," came back the answer. "Luckily I've managed to get hold of a rock and stopped my tumble. But don't waste any time lending me a hand, Frank, because it seems to me I feel the thing move. If another quake comes it'll let me drop; and perhaps the ground may be a full dozen feet below."
By this time Frank had reached the edge of the drop. He remembered skirting it in climbing upward just a minute before; but had been more successful about doing so than Bob, who was less accustomed to this kind of work.
Frank again had recourse to his handy match-safe. Leaning over he struck a match on the face of the rock. Immediately he drew a quick breath. It was not because he could see the face of his chum only a couple of feet away, as the latter clung to a spur of rocks; it was something else that thrilled him.
As far down as his eyes could see there was only a black void! Instead of the simple dozen feet mentioned by Bob, the yawning precipice extended perhaps a full hundred feet downward!
But there was no need of telling Bob that it might alarm the boy and cause him to weaken, so that his grip would give way.
Frank was quick to understand what must be done. He could just touch the hand of his chum by bending far down; but that was not enough. Instantly he wrapped one leg about a sturdy, if dwarfed, little cedar that chanced to grow at that very spot, as if designed for the very purpose to which he was putting it. Then he was able to thrust himself still further down the face of the wall.
"Take hold, and grip like iron, Bob," he managed to say.
He felt the other obeying him, and thus they caught hold of hands.
"Now, try and dig your toes into the face of the wall if you can," Frank went on, calmly, so far as Bob could know. "It'll help me get you up. Climb over me. I've got a leg around a cedar, and nothing can break away. Now!"
"Say, perhaps you'd better let me drop down." said Bob, thinking his comrade was going to unnecessary trouble in order to save him from a little jolt.
"Climb, I tell you!" snapped Frank.
"Oh! all right, Frank, if you say so," and Bob started to obey.
Fortunately he was an agile lad, and a very fair climber, for the task which he had set himself was no ordinary one. But, by wriggling more or less, Bob managed to finally get a grip on the cedar. After that it was easy work; and having succeeded in reaching solid ground himself, he aided the almost exhausted Frank to draw back.
"Whew! that was some work, now, and all because I was so silly as to slip over the edge of that little hole!" remarked Bob, as though disgusted with himself.
"Look here," said his chum; "lean over carefully, while I drop this match down."
As he struck the match, and then cast it from him it went downward twenty, thirty, forty feet before it was extinguished.
"Ugh!" shuddered Bob, "why, it must be all of a thousand feet down to the bottom, Frank! It scares me just to think of the narrow escape I had."
"Well, I reckon it's all of one hundred feet," replied Frank; "and that's enough to settle a fellow. But let's lie back here, and get our breath a bit before going on up. The cave can't be far off now, if what Joe said is so."
Both of the boys were panting after their unusual exertion, and Bob was glad of a chance to rest for even a brief time. Besides, another burst of thunder was starting in, and he fancied that it was louder than any that had gone before; just as if they might be drawing closer to the place from whence all this clamor came.
The cave that Spanish Joe had found and entered—could it have anything to do with the mystery of the mountain? Frank seemed to think so, and was bent upon ascertaining the facts.
"Listen to that, Frank?" shouted the Kentucky lad in the ear of his mate, while the racket was at its height. "I can hear rocks dropping all around, just like the one did where Joe was grabbed by the leg. Do you think this always happens when the old mountain breaks loose; or is this an extra big celebration?"
"I was trying to get that myself, Bob," admitted Frank; "but we can only guess at it, because you see, nobody's ever been up here when the thunder was rocking the whole range, and so we don't know. But, honest, now, I'm of the opinion this happens only once in a great while; else the mountain would have been racked to pieces long ago."
"And just to think, we had the nerve to come here at a time when it was bound to do its worst," said Bob.
"Glad of it," Frank immediately returned. "It gives us a better chance to learn a few things worth while. I always did like to be in where the roping was fastest. Are you feeling better, Bob?"
"Oh! yes, I reckon I'm all right now," returned the other, rising.
"Ready to go on, then?" continued Frank.
"Try me, that's all. If I turn tail and run, don't ever speak to me again," came the steady, but not boastful, answer.
"Good boy! All right, let's be off again; and be mighty careful how you move. There may be more of those drops lying around loose. And next time you mightn't be so lucky about grabbing a spur of rock."
"That's so, Frank. Wow! but it makes me shiver to even think of it. Talk about Joe's narrow squeak, it wasn't any worse than mine," and Bob started to crawl after his better-trained chum.
Two more evidences came to them of the violence of the unseen force that was making Thunder Mountain shake, before Frank stopped to let his chum reach his side, so that he might exchange a few sentences.
"Looks like that might be the hole ahead," he ventured.
"I can see something that seems blacker than the night itself; is that what you mean, Frank?" asked Bob.
"Yes," his chum continued. "When Joe pointed up this way I took note of just the line, and followed it closely. That was why we came so near the precipice. And if that is the opening to the cave, we want to lie here and listen."
"Why, do you really believe the racket comes out of that hole?" demanded Bob, astonished at the very idea of such a thing.
"Wait and see," replied the other, confidently. "In the meantime, here's our opportunity to pick up a few candles that will come in handy."
They had come to a halt directly under a tree; and Bob had already discovered that the ground was thickly strewn with broken branches. Some of these were apt to be fat with the inflammable gum that exudes from certain species of cedar, and would, as Frank said, make splendid torches.
Frank was already on his hands and knees searching for suitable ones; and as Bob grasped the idea he, too, set to work.
"I have four already; how do you stand?" asked Frank, presently.
"Just as many—no, here's the fifth one, and the best of the lot," came the reply from the Kentucky lad, who went into everything with ardor and enthusiasm.
"That ought to do for us," Frank went on. "And now, listen for all you're worth, because the war is on again!"
Lying there, Bob heard what seemed to be the first signal. It was as though some giant hand had tapped the solid rock with his club. Then faster came the blows, and more and more did the din increase, until it was fairly deafening. Only for his intense eagerness to hear every sound Bob might have been tempted to thrust his fingers into his ears in order to shut out the awful clamor.
To him it seemed as though a thousand anvils were being beaten in chorus, with a few other minor chords thrown in for good measure.
And what interested Bob most of all, as he crouched there listening, was the fact that all this dreadful noise seemed to be coming directly from the spot where his comrade had pointed out as the opening of a cave.
There was not the faintest trace of lightning accompanying the manifestation; and this proved, beyond all question of dispute, that the mystery connected with Thunder Mountain had nothing to do with an electrical storm. Possibly the observing Indians had many years ago discovered this same thing; and it had strengthened their belief that the great Manitou spoke to his red children through the voice of the wonderful mountain.
It took longer, this time, for the noise to die away; just as though, whatever its cause, there was increasing reluctance to subside again.
"That was a screamer, sure enough!" said Frank, when he could make himself heard above the declining roar.
"And Bob, you noticed, didn't you, that it seemed to come right out of that hole? All right, it begins to look now as if we were Johnny on the spot, if we've got the nerve to push things. Somewhere in there, Bob, lies the explanation of the mystery. Do we take the dare; or stay out here and wait till the fuss is over before entering?"
Bob possibly swallowed hard before replying. It was no easy thing for him to say the words that would thrust them up against so terrible a thing as this unknown peril awaiting them in the gloom of that crack of the great mountain. But his hesitation was brief. In fact, he only wanted to catch his breath, shut his teeth hard together, and summon his Kentucky blood.
"It's a go, Frank!" he said, with determination in his voice; "the chance may never come to us again. Let's go in, and discover for ourselves the secrets of the Indian god they say is guarding Thunder Mountain. I'm ready, so lead on!"
"No hurry," said Frank, who realized that his comrade was worked up to a high pitch of excitement, and thought it the part of wisdom to do something in order to quiet Bob's nerves.
"But if we've got to try it, Frank, what's the use of waiting?" demanded the impetuous one.
"Well, for one thing, we don't want to be carrying these candles without making use of one, you see," replied Frank, who was again getting out his handy matchsafe.
"What a silly I am, to be sure," laughed Bob; "why of course we want a light, if we're going to invade that den of the demon Joe told us about. What do you think about that yarn, Frank; did he meet up with anything; or was he just scared out of his seven senses? Perhaps there's a strong current of air in that place, along with the noise, and that took hold of Joe."
"Well, I wouldn't like to say," replied the other, cautiously. "This I do know, and I saw it with my own eyes. Joe's fancy Mexican jacket was torn nearly into ribbons; and I could see marks of blood, too."
"Whew! you don't say?" ejaculated Bob. "Then somethingdidget hold of him; didn't it, Frank?"
"Looked like it," admitted the other.
"His jacket was torn into ribbons, you said—then I reckon whatever tackled Joe had pretty sharp claws, Frank!" Bob continued.
"I thought as much myself. In other words, Bob, the man was attacked by some wild beast that has its den in yonder. In the dark, with all that terrible noise going on, Joe thought it was a monster from the underworld. If he keeps on telling that story, ten to one, after a while, he'll vow it had eyes of fire, and a tongue of blue flame. Joe was frightened half to death, and a man in that condition gets to seeing things that never did exist. Now, how's that?"
While speaking Frank had managed to light one of the cedar torches he carried. The wood burned readily, and with persistence. It would make a good substitute for a lantern. Indeed, Bob was enthusiastic over the success attending his chum's effort.
"Couldn't be beat, that's what!" he cried.
"Well, there's nothing to keep us now," declared Frank.
"But what can I do?" asked the other. "Want me to light a torch too, Frank?"
"No, one ought to be enough. You fall in just behind me, and Bob, perhaps you'd better keep your gun handy."
"Oh! you're thinking now of that demon Joe told about, eh, Frank?"
"Perhaps. If it jumps out at us give a center shot, if you can," the saddle boy advised, as he led the way forward toward the black spot which they had guessed must be the cave entrance spoken of by Spanish Joe.
They were quickly at the wall, and had no difficulty in learning that, just as they had guessed, the yawning hole was there. Frank, without the slightest hesitation, stepped through the opening. Bob did likewise, holding his gun in readiness for immediate use.
The light of the blazing torch lighted up the interior. They could see that, so far, there was nothing remarkable about the cave, save that it seemed to stretch away into dim distance, with various twists and curves.
"What are you sniffing about, Frank?" demanded Bob, who, in the silence, heard what his comrade was doing.
"I think I scent something, that's all," replied the other.
"Not brimstone and sulphur, I hope?" cried Bob.
"Well, hardly," chuckled the other. "In fact, it seemed to me that it was only such an odor as you can always detect around the den of a wild beast!"
"Glory! then Joe didn't dream it, after all; and there may be an old grizzly in this cave!" ejaculated Bob.
"Not a grizzly," declared Frank, quickly. "If anything, I think it must be a panther. But he may have left after attacking Joe, so that we'll have no trouble with the beast."
"I hope so," Bob remarked, as he strove to look seven ways at once, keeping his finger on the trigger of his repeating rifle all the while.
They were now advancing into the cave.
"Do you think Joe had a torch?" asked Bob, as a new idea came to him.
"Well, he isn't the man to take chances, and he couldn't help but see the good torch material at the door yonder. But the beast may have jumped on his back, so he lost his torch before he could see. And then he fought in the dark. Joe has always been known as a hard fighter, and with his knife I reckon he could give a good account of himself. Hello! see here!"
Bob started when his chum gave this sudden exclamation.
"Oh! I thought you had sighted the panther!" he gasped as he lowered the gun, which had, perhaps through mere instinct, gone up to his shoulder.
Frank was bending down. He held his torch in such a fashion that he could see better; and he appeared to be examining something on the rock.
"What is it?" asked Bob, eagerly; "footprints?"
"No, just a little spot of blood," came the reply.
"Fresh, too, I can see," declared the tenderfoot, as he looked. "Does that mean this is the exact place where Joe had his little circus, Frank?"
"I reckon it is," replied the other.
"Then if that beast hasn't cleared out we might run across him before long!" remarked Bob.
"Oh!"
Frank gave utterance to this cry. He had seen some object flash through the air, and knew it could be nothing else than the lithe body of a panther making a leap.
The animal must have had a place of hiding close by, from which it had probably jumped upon the shoulders of Spanish Joe, and now sought to repeat that act.
Bob was struck by the descending body of the animal; and while he did not suffer serious injury from the blow, it jarred his arm, and caused him to drop his rifle. He instantly leaped forward to recover the weapon, but through chance picked it up by the end of the barrel.
The panther had recovered, and was crouching as though to repeat its jump. Only a yard lay between the fierce beast and the boy who held the gun. Perhaps a veteran hunter would have proceeded to reverse the weapon, and discharge it without taking the trouble to throw the stock to his shoulder. But Bob did not dream that he would be given enough time for all this.
He saw the beast there close to him, and his first thought was to poke the butt of the rifle directly at its head, striking with all his force. The blow landed heavily, but as the beast gave way, Bob lost his balance, and fell directly toward the panther.
It looked as though the boy might be in for a terrible clawing, and so it must have turned out had he been alone. But he had a comrade close at hand who did not hesitate an instant about taking part in the affair.
Frank could not get at his gun, which was slung across his back; but he knew he had a better weapon than that in hand. Wild animals dread fire above all things; and every lad brought up on the prairie knows this fact.
Suddenly Frank brought down his torch upon the beast with all the force he was capable of using. There was a snarl and the animal jumped aside, evidently not fancying the closeness of the stick that burned. The lad again raised his torch, but evidently the panther had already endured quite enough of the conflict. It was bad enough fighting two human beings at a time; but when one of them persisted in belaboring him with such a hot weapon he drew the line.
And so with a parting snarl, that was full of defiance and venom, the panther sprang back out of sight, departing just as silently as he had come.
"That's just like the luck," grumbled Bob.
"What's the matter now?" asked Frank, looking sharply to make sure that the treacherous beast did not sneak back in order to attack them from another quarter.
"Why, I'd just got my gun slewed around, and was ready to fire when he skipped out. I'd liked to have bagged him, I reckon. A grizzly and a panther, all on one trip, would be worth talking about."
"Oh! I don't know that you'd have been so very proud over it," observed Frank.
Bob looked at him as he said this.
"Now, you've got some reason for making such a remark as that," he observed.
"Perhaps I have," answered his chum, nodding wisely.
"Then out with it, Frank, and don't keep me wondering. Besides, I reckon that we'll have another bellow from the old mountain at any time now."
"I guess you didn't notice something queer about that animal, then, Bob?"
"About the panther, you mean?" came the reply. "Well, to tell the honest truth I was knocked all in a heap when I missed hitting him, and didn't have time to bother looking at him close enough to see anything. But what was so funny about him, Frank? Did he have only one eye; or was he three-legged?"
"Oh! nothing of that sort," declared the other; "so far as I know he is in possession of all his members. It was about his neck."
"What about it? Did he have a rubber neck, you mean?" demanded Bob, trying to be a little humorous so as to conceal the fact of his excitement.
"The beast had a collar on!" Frank remarked, positively; "and that means he must be the pet of somebody who has a hiding place in this cave!"
As Frank made this astonishing declaration his chum looked blankly at him, the information having evidently surprised him not a little.
"A tame panther, you mean, Frank?" he exclaimed, weakly.
"That's just what I'm hinting at," replied the other, positively.
"With a collar around his neck, too?" murmured Bob.
"Yes. I saw it as plain as I see you now," Frank went on. "It was when I jumped forward, and gave him the first crack that made him fall away in a hurry. A collar that was broad and stout. Why, Bob, when he threw back his head to avoid punishment I could even see where a chain could be fastened, and the animal kept in confinement."
"Whew! but he acted like a wild one, all right," protested Bob.
"He sure did, Bob; but that was because he had already been stirred up by the fight with Spanish Joe. I reckon the cowboy must have give him a few jabs with that handy knife he owns. Anyhow, the panther was spoiling for a scrap, and didn't care a cent how many there were."
"That was before you gave him his finish with that fire-stick, Frank. Didn't that knock the old chap silly, though? Why, it took all the fight out of him, for a fact. He was the tame panther all right when he ran away, with his tail between his legs. Think he'll tackle us again?"
"No telling; but I don't believe the beast cares much for running against my torch again. It might pay for both of us, though, to keep on the watch," Frank replied, always on the side of caution.
"But I say, Frank, is the fact that he's private property going to make any difference; that is, do I shoot straight if I get the chance again?"
"Well, I say yes," answered the other. "Given half a chance and he'd maul us the worst way. No matter who's property he may be, I'd advise him to keep clear of Haywood and Archer. They're marked, dangerous—hands and claws off, but come along, Bob; let's be moving."
"Wait, there it comes again, Frank. Don't you think we'd better lie down till the worst is over?" ventured Bob, as he caught the opening notes of the mighty anvil chorus that would soon be in full blast.
"Well, now, perhaps that wouldn't be a bad idea, Bob. Suppose we do stretch out here, you facing one way and I another."
The two crouched there. Frank had thrust the torch into a crevice, for he wanted the use of both hands in gripping his rifle. If the wild beast guardian of the cave tried to attack them again, he felt that he would like to be in a position to shoot.
"Feel the wind, will you?" called Bob, as the sounds mounted higher and higher.
"I'm afraid our torch is going to be blown out," Frank replied, pointing to the flaring light, which was being hard pressed by the suction that seemed to rush through the cave, heading always toward the mouth.
"Say, Frank, the air feels wet!" shouted Bob, while the racket was at its height.
Of course this was no special news to Frank. He, too, had noticed the same thing, and mentally commented on it. And as it was in line with certain suspicions which he already entertained, he had felt amply repaid for taking such hazards in plunging into that black cave.
Then suddenly an extra strong blast put the torch out.
"Wow! there she goes, Frank! What will we do now?" yelled Bob, of course feeling a new uneasiness because of the intense darkness, the presence of an angry animal near by, and the general air of mystery that hung over the scene.
"Nothing. Just wait till the storm blows by; and then we'll light up again," was what Frank shouted back at him.
Already it was diminishing. Like the receding waves of the great ocean the uproar died down, growing fainter with each pulsation.
And finally there came again the silence that in one way was almost as dreadful as the clamor; during which Frank proceeded to light the torch again, though not without some difficulty.
"Frank, you felt that wet sensation, like fine spray, didn't you?" demanded Bob, as soon as he could speak with comfort. "Why, touch your face right now; and you'll find it moist. Whatever can it mean?"
"I think I know," Frank said, slowly. "I suspected it before, and this seems to make it look more than ever that way."
"Do you mean that you've guessed what makes all that frightful noise?" asked Bob, astonished.
"I believe I have," came the reply.
"And it has to do with this misty feeling in the air; has it?" continued the Kentucky boy.
"If my idea proves the right one, and I'm bound to find out before I go away from this place, it's got everything to do with it, Bob."
"Where there's smoke you'll find fire; and where there's mist I reckon water can be looked for," remarked Bob, quickly.
"Just so. Now Bob, have you ever been up in the Yellowstone Park region?"
"I can't say that I have, Frank."
"Then you see I've got the advantage over you; and that's what gave me a point in the game. Because I've stood and watched Old Faithful and the other great geysers play every half hour or so," Frank went on, as they slowly advanced into the passage which seemed possibly to act as one of many funnels through which the tremendous roaring sound was carried to the outside world.
"Geysers!" cried Bob. "Oh! now I get onto what you mean. You think, then, that in the heart of Thunder Mountain a giant geyser spouts every once in a while; and that as the water is dashed against the rocky walls it makes the ground shake. Is that it, Frank?"
"Yes," replied the other, "and the noise is so like thunder that when it is forced out through several queer, funnel-shaped openings like this one, it has puzzled the Indians for hundreds of years. Bob, more than that, I believe that every once in so many years, when an extra convulsion shakes things up here, the water bursts out through some passage, and rushes down thatbarrancain a wave perhaps twenty feet high."
"But they call it a cloud burst, Frank," suggested Bob.
"I know they do, but still I stick to my idea," Frank went on.
"And this promises to be an extra strong outburst. Nick said so anyhow; didn't he, Frank?" Bob queried, a new anxiety in his tone.
"Just what he did. You're wondering now, that if what I said is true, whether this passage right here is one of those through which all that water dashes, on its way to the rockybarranca?"
"Yes, that's the truth. How about it? Could you see any signs here to tell about that?"
"I suppose I could if they were here, but I don't discover any. Besides, I thought of that before we entered, and I give you my word that I don't believe any big volume of water ever went out through here. It couldn't do it and not leave some sign behind."
Bob heaved a big sigh.
"Well, I'm right glad to hear you say that, Frank, seeing that we're so far in now, we wouldn't have any chance to escape if it came along. Whew! I wouldn't like being carried through here, and shot out of the muzzle like a bullet. But seems to me the place is getting bigger right along, Frank."
"Just what it is. Now you can see how like the neck of a bottle the cave is; and I think that has had a heap to do with the way that thunder noise gets loose. Why, they say that some days, or nights, it can be heard more than twelve miles away. I've seen Navajo Injuns drop flat on their faces, and lie there all the time we could hear the distant thunder in a clear sky over our way."
"But is it possible that some hermit is living in this cave?" asked Bob, thinking that it must be a queer sort of person who would remain where he must listen to such fearful sounds every once in a while.
"I told you to notice when we heard the noise the first time," Frank went on; "while we were in camp on the plain, that the night was clear, and the wind almost in the Southeast. Well, I made sure that it was in exactly the same quarter tonight when we were climbing the mountain. That means something, Bob."
"To you; but to me it's only a blank," admitted the tenderfoot, regretfully.
"I fancy that the direction of the wind has something to do with the working of this queer old geyser in the heart of Thunder Mountain. It only rears up when the wind is in the Southeast, as it is now. But say, you said something about a hermit just now?"
"I only said I thought it strange a fellow could live here through all the racket, year in and year out, just to get away from his kind," Bob remarked.
At that Frank laughed.
"But what if he had a big object in it, Bob? What if some daring prospector, taking his life in his hands, had plunged into one of these caves of the winds, this one right here, for instance, and struck it rich. Gold will make men do nearly anything. I've seen 'em go crazy over finding a nugget, or yellow sand in their pan. Don't you see what I mean, Bob? Have you forgotten little Lopez, and how frightened he looked when we spoke about keeping him company?"
Bob uttered a cry that might stand for either astonishment or delight, perhaps both.
"Frank, it just takes you to see through the mill stone, even if it hasn't got any hole in it," he declared. "I understand what you mean now. Little Lopez has been coming here for a year or more, always bringing supplies. Perhaps he carries away the gold dust the miner has gathered in that time, and no one the wiser. It has all been a dead secret. And the terror of the Indians for this haunted mountain, as well as the way the cowboys leave it alone, has helped this bold miner. Frank, your shot hit the bull's eye, and who knows but what we may be on the way to find out the truth right now?"
"Now you know what I think, Bob; but after all I may be on the wrong track," said Frank, after his companion had expressed himself so freely.
"Of course," Bob went on saying; "but all the same I don't think you are. After you've shown me, it's just like that egg Columbus stood up on end, after cracking the shell a bit—as easy as jumping off a log, once you know how. But now we're in here, I hope we find out the truth soon, don't you, Frank?"
"Honest now, Bob, I don't care how quick it comes," replied his chum, frankly.
"This is a terrible place, with panthers hanging around, and that thunder banging to beat the band every minute or so. I'm only wondering, Frank, what would become of us if that old geyser should take a notion to explode suddenly, and flush every avenue out of the heart of the mountain."
"Don't mention it, please," Frank answered, with a shrug of his shoulders. "If such a thing happened we wouldn't know what hurt us, I'm afraid."
"Huh! some consolation in that, anyhow," grunted Bob. "If a fellow has to go up against the buzz-saw, the sooner it's over the better."
"But nothing of the kind is going to happen," Frank insisted; "and you want to get the idea clean out of your head. We're making fine progress, and any minute, now, I expect we'll run across the party who occupies this cave."
"But every time the blowout comes, away goes our light; and another spouting is about due now, I reckon," ventured Bob.
"I've got an idea I may be able to save the torch," Frank remarked. "I don't know just how it's going to work; but anyhow the thing's worth trying."
"Then here comes your chance," his chum called.
As before, the grumbling began with an earth tremor. It was as though some giant, whose mighty limbs were shackled, was trying to break loose; and in so doing made things near him tremble.
Rapidly the noise increased, until it became terrifying. Bob had dropped flat, and cowered there, almost holding his breath with awe. Not so Frank, in whose care was the burning torch.
He had whipped off his coat at the first sign of the disturbance. This he hastily arranged so as to partially protect the burning brand. Of course in such a violent draught the suction was enough to make the flame flare and flicker until at one time Frank feared it could not stand the struggle. But just as he was ready to give up the attempt, the furious wind seemed to slacken.
Bob raised his head to see the torch still burning, and it soon recovered its full capacity for illumination.
"Bully!" he exclaimed, beginning to rise from his position of hugging the rocky floor of the cave; "you did it that time, Frank. But hurry up, and get your coat on. Gee! but this air feels chilly in here, and damp too!"
Frank had found that out for himself. He was even shivering; and made haste to don his jacket.
"Now let's be moving while we have the chance," he said. "I hope that before the next rush comes we'll sight what we're looking for."
Perhaps his sharp eyes had discovered certain signs that told him they were near the working part of the cave. Men cannot mine a lode of precious ore without leaving many traces behind to tell of their presence. And the stream of clear water that passed across the place seemed to offer a splendid chance for panning any golden treasure that might be found in the shape of soft quartz.
Now and again Frank would place the torch behind him. Bob wondered what he did this for until he saw his chum bending his head forward as though endeavoring to discover what lay ahead. Then he realized that the light blinded him while it was before his eyes, and he sought to avoid the trouble in this way.
"There's another bend ahead, Bob," Frank remarked, presently.
"Yes?" said the Kentucky lad, eagerly, suspecting what was coming.
"And I can see signs of light at the curve," Frank went on.
"Hurrah! Everything seems to be coming out just as you figured, Frank. When I get back to the ranch I'm going to write to the president, proposing that he put you in charge of the weather bureau. Every old farmer will know then when to look out for storms."
"Well, we may be in for one now," observed Frank, dryly.
"Look here, you mean something by that remark," Bob cried. "Do you expect we're going to have a peck of trouble with these miners?"
"I don't know. It all depends on what sort of men they are," Frank replied.
"But we wont let 'em drive us out of here until we know all about that geyser, if there is such a thing; will we, Frank?"
"Well, I reckon it won't take a great deal of driving to get both of us out; but of course I do hope we'll learn something about the real cause of all this awful racket. Are you ready to turn the bend, Bob?"
"Sure," and the Kentucky boy ranged alongside his chum, by this movement plainly indicating that he did not mean to let Frank take any more risk than he himself was ready and willing to assume.
No sooner had the two saddle boys turned the bend in the passage than they saw a singular spectacle.
A couple of lanterns were hung from wooden pins driven in the wall. These lights, being protected by glass, could safely resist the tremendous suction that accompanied each successive convulsion, as the rocks trembled, and the air swept through toward the outer exit.
Only two figures were in sight—a man and a boy. In the latter they recognized little Lopez, the hero of the adventure with the grizzly; and if their suspicions proved true also, the little girl whom Bob had rescued from the anger of the bully, Peg Grant.
The man was a rugged specimen, with long, iron-gray hair. Frank recognized him as Lemuel Smith, whom he remembered to have met several years ago when in a border town with his father.
Smith had always been a rolling stone, a prospector who spent his time in hunting new strikes, and who lived year in and year out in the wild hope of sometime or other hitting it rich. Frank suddenly remembered that Smith had had one daughter, who, he believed, had married a Mexican. And that would make the little girl his grand-daughter.
"They're packing up," remarked Frank, whose quick eye had noticed the fact.
"Perhaps he's done his work here, and means to vamoose the ranch," Bob suggested. "Then again," he added, as another thought raced through his brain, "maybe he doesn't altogether like the looks of things, and wants to get out of this rat-hole before it all goes to smash. He must have been here a long time, and ought to know something about that geyser, Frank."
"There, they have discovered us!" the other exclaimed, as he waved his torch in what he meant to be a friendly way, and kept on advancing.
"Whew! I just hope he doesn't try to fire on us," muttered Bob, who was nervously fingering his rifle, and wondering how dreadful it would feel to be compelled, even in self-defense, to shoot at a fellow human being.
But the old miner held up both hands. It was the Indian peace sign, understood by every savage tribe on the face of the globe.
Quickly the two boys hurried forward, for the first symptoms of another burst of thunder and furious wind began to make themselves felt.
This time Frank did not take off any of his outer clothing in order to protect the torch. He had noted that the old miner hadtwolanterns, and he expected to borrow one, if necessary.
Of course his torch was snuffed out while the furious blast swept by. Bob noted that each successive outbreak tried to beat the record, and he was wondering just when the limit of endurance might be reached.
The old miner, after the roar had subsided, offered the two boys his hand.
"How are ye, young Haywood?" he asked, recognizing Frank. "I heard about what you done for my little gal here, Inez Lopez, whose father was once a cowboy on the Circle ranch, and lost his life in a fight with some of his countrymen when they quarreled. I'm glad to see you. Found a nice little pocket here a year or so back. Kept it on the quiet; and the gal, playing the part of a boy, has been fetchin' me supplies once in two months, an' takin' away the dust I winnowed. Pocket's played out now, but I reckons as how I've got plenty. 'Sides, I just don't like the way things is agoin' here. That spoutin' geyser that rises up inside the old mountain every once in a while acts like it meant to break loose. Never saw it carry on that bad before; and we're just ready to cut and run, leavin' most of the truck behind. What brings ye here, Frank?"
So Frank had to explain in a few words, while the old miner looked admiringly at the boys, and grinned.
"I admire your nerve, young fellers," he declared, at the conclusion of the explanation. "And, Frank, ye guessed the true facts, blessed if ye didn't! I got onto the same by accident. Fell in through a hole, and just had to creep along this passage to the end. Then havin' guessed what made the roar, I wondered if so be I could find any stuff in here. So I took a lot of wood along, and made my discovery."
"And you say you're bound out now?" asked Frank.
"That's what we are, little Lopez and me; and we can't get to the open any too soon, either, to please both of us," Smith replied, shouldering his pack.
"Oh! say, Mr. Smith," cried Bob, "have you lost a pet that wears a collar?"
"Meanin' my pet painter, Nero, I take it," replied the miner. "I raised him up from a cub, and he's as fond of me as my dog. But he's gone somewhar. We ain't seen him for hours, and like as not the critter knowed it was gettin' dangerous in here. Trust animal sense for that. But wait till this next whoop gets by, and then we'll make for the door. Here's hopin' we'll all be smart enough to get to the open. Bend your backs to the wind, boys; ye wont feel it so much then," and all of them carried out his instructions as, with a rapidly rising roar, the spouting geyser that played in the heart of Thunder Mountain again started to break loose.
Once the little party started toward the opening, they made rapid progress. The turmoil was at their backs, for one thing. Then, again, each time the noise broke forth it seemed so much worse than before, that every one felt anxious to get beyond the portal of the cave before the climax came.
And when finally this opened before them, Bob drew a long sigh of relief.
"Glory!" he burst out. "Maybe I'm not glad we've arrived! But I reckon your pet, Nero, has skipped, Mr. Smith, or he would have come out when you and the little Lopez passed. Sorry for you; but perhaps it's just as well for the rest of us; because you see the fellow might have had it in for us."
So they passed into the outer air.
"Seems pretty much the same as when we left," remarked Bob, as he stared up at the dark sky against which they could see the rocky crown of Thunder Mountain dimly outlined.
"Why, what did you expect?" asked Frank.
"I didn't know but what some of that thunder might be the genuine article, and we'd find the rain coming down to beat the band. Glad it isn't, because we want to get down from this to where our horses are."
"Little Lopez has our burro and bronco quartered in a small ravine where they can't escape," remarked the old miner, as he handed Frank the lantern he had been carrying, the girl taking the other.
"But would they be in danger in case of a storm-burst?" asked Bob.
"We counted on that when we arranged the exit by piling up stones," came the ready reply. "There is little danger, for the ravine has high banks, where they are able to go in case of hard luck. But now we have a tough job ahead, boys. Mind your steps all the time. A slip might cost you dear."
"Reckon I know that, Mr. Smith," remarked Bob. "I've had experience, you see. And only for the helping hand of my trusty chum here, I'm afraid I wouldn't be alive right now. Oh! I'll be careful, I give you my word."
And he was, seldom putting a foot forward without first making certain how the land lay below, and that the stone he expected to step upon was firmly planted.
They were making fair progress when the old miner called out:
"We've reached the parting of the ways, boys. Little Lopez and me have to turn to the left here, so as to hit the place whar our animals are cached. You keep right on. Wish you the best of luck, Frank. Hope to see you some time at my shack. And I tell ye, son, thar's agoin' to be a ranch soon, with hosses for the gal, an' an ottermobile for the old couple. I struck it rich in this here lode and pocket. So-long, boys!"
He shook hands with each of them, as did also the girl, whose astonishing nerve, when facing that terrible grizzly, Bob would never forget. Then they separated. And a minute afterward there came another of those fearful shocks that seemed to make the very rocks of the mountain quiver, as the pent-up force of that great geyser beat against its prison walls.
"We must be getting down somewhere near the canyon, aren't we, Frank?" asked Bob, after they had been a long while descending the side of the rough mountain.
"That's right, we are," replied his chum. "And I've been wondering whether we ought to take the chances of going along thatbarrancajust now."
"It's the shortest way to where we left our horses, I reckon," remarked Bob.
"And the only way we happen to know of," Frank went on; "but if that flood just happened to break loose while we were between those high walls we'd have an experience that would be fierce, let me tell you!"
"But then, it may not come for hours yet?" remonstrated the Kentucky boy, who was anxious to be once again in the saddle, and leaving the haunted mountain well in the rear.
"Oh! for that matter, it may not come at all," Frank went on. "Although Smith did say he really believed that this was going to finish the old geyser, which he believed empties into one of those queer underground rivers we know are to be found all through the Southwest. And Smith ought to know something about it, for he's been watching this business a whole year now, from close quarters."
"I'm willing to take the chances, if you are," declared Bob.
Frank was not at all surprised when he heard his chum say this. He knew that the Kentucky boy was apt to be rash; and that meant more caution on his part, in order to counteract this spirit, that might border on recklessness.
A quick decision had to be made, for delay could do them no good. He cast one last look up at the dark heavens, as though questioning how long they might remain mute.
"All right, we'll risk it, Bob," he declared, suddenly; for even if the worst came Frank believed he knew how to avoid a calamity.
"Good for you, Frank!" exclaimed the other; but Bob understood the nature of the risk they were taking, and he was not quite so buoyant as usual.
The canyon was just below them now, and fortunately there seemed a narrow bit of slope down which they might make their way. This they did with considerable difficulty. Indeed, Bob was secretly sorry, after they had started, that he had urged his companion to take this step; but there could be no going back now.
Finally, after several slips, and more or less excitement, they managed to gain the bottom of the canyon.
"Say, I don't remember this place any, Frank!" declared Bob, as he stared about him as well as he could by the flickering light of the lantern which his companion still carried, and which had served them well through all their descent.
"For a mighty good reason," replied Frank. "We were never here before."
"But this is the same old turtle crawl, isn't it; thebarrancawe followed up to the time we climbed the slope with our horses?" Bob asked.
"It sure is, only a lot farther along, Bob. Notice how the walls tower upon each side. I knew something about this, and that was why I held back when you wanted to come down here. But let's hurry. We've got to make that slope as soon as we can."
"Supposing the thing broke loose before we could find any place to climb out?" suggested Bob, looking up again with awe, as he stumbled along after his chum, who was already hurrying down the canyon.
"We might try to outrun it first," Frank replied, over his shoulder.
"And if that didn't work, what then?" the other continued.
"Nothing left but to climb the walls, Bob."
"Whew! then perhaps I'd better be keeping an eye out as we go along, and see how the land lies?" suggested the boy from Kentucky.
"A good idea, Bob. Just notice where the chances look half-way decent for a climb. And remember, at the same time, that the wave may be all of thirty feet deep when it sweeps through here."
"You don't say? That would mean some hustling then to get up out of reach, Frank."
"I reckon it would. Look out for that nasty rock; it nearly tripped me, Bob."
"What was that flash, Frank? Don't tell me it was lightning, real lightning, and that the long delayed storm is going to break right now, when it's got us cooped up in this hole?"
"It was lightning, all right. There, that proves it!"
Frank's words were drowned in a crash of genuine thunder that made the foundations of the mountain shake just as much as the mad efforts of the imprisoned geyser had ever done.
"No mistake about that sort of thing," cried Bob, as he stumbled along after his chum. "There it comes again, Frank. I guess I'd better be picking out a good way up the wall somewhere, for it looks like we'd have to climb!"
Frank was doubtless sizing up the situation in his mind. He was also listening for some sound which he expected to hear, but which was going to prove a very unwelcome one.
"No use going any further, Bob, if so be you've seen anything that looks promising here," he declared, when the reverberations of the thunder had ceased to echo through the canyon.
"Then you think we're going to get caught here, Frank?" questioned the other.
"I'm afraid to take the chances of keeping on any further. It may be a long run to the next broken wall, that offers us a chance to climb. Some places the sides go up as smooth as glass. Have you see an opening here, Bob?"
"Yes, yes, right on the left, Frank!" exclaimed Bob, eagerly. "I couldn't see so very far up, but it looks good to me."
Frank turned his gaze up to where his comrade pointed.
"I think it's rough as far as that ledge," he said; "and let us hope that will be out of the reach of the water. Come on, Bob; let's see how you can climb; but be careful, boy, be mighty careful!"
"Frank, that roaring sound didn't seem like the others we've been hearing; d'ye think it means anything has happened?" Bob called, as he started to clamber up the rough face of the wall, taking advantage of every jutting rock, and showing a nimbleness a mountain goat might almost have envied.
"I reckon it does, Bob," replied the other. "Get along as fast as you can with all caution."
"Has the cloudburst arrived?" demanded Bob, who was already ten feet from the floor of the canyon.
"Either that, or else with that last shock the geyser burst its bonds, and the flood Smith expected is rushing out from all the passages into this same channel! Perhaps both things have happened at the same time," Frank replied.
"Wow! then we'd better be climbing some, I reckon, if that's the case!" cried the Kentucky boy, as he increased his efforts to ascend to the ledge.