"Pull up, Bob; I sure glimpsed something moving, out there in the sage brush!"
Both horses came to an immediate stop as the bridles were drawn taut.
"Which way, Frank?" asked the Kentucky lad, eagerly, as he threw back his shock of black hair, and waited to see where the finger of his companion would point.
"Whatever it was disappeared behind that spur of the low foot hills yonder. I just caught a peep of the last of it. Here, Bob, take the glasses, and wait to see if it shows up again on the other side of the rise," and Frank thrust the binoculars into the hand of his chum.
"Think it could have been a prowling coyote; or perhaps a bunch of antelope feeding on the sweet grass around some spring hole, as you were telling me they do?" asked Bob, holding himself in readiness.
"Well," returned Frank, quickly, "the sun was in my eyes some, you see, and so I wouldn't like to be too sure; but somehow, Bob, I just have a notion that it was a horse."
"With a rider on it, of course!" exclaimed the other lad, as he raised the glasses to his eyes, training them on the further end of the squat elevation that stood up in the midst of the sage level like a great hump on a camel.
"There, looks like I was right, Bob!" ejaculated Frank, a minute or so later, as something came out from behind the low hill, moving steadily onward.
"Indians! as sure as anything!" fell from the lips of the one who held the field glasses to his eyes.
"One—two—three—a heap of the reds in that bunch, I reckon," muttered Frank, watching with his naked eye; although the distance, separating them from the spot where the figures were passing steadily into view, was considerable.
"Say, these glasses are jim-dandy ones, all right!" remarked Bob, presently, as he turned to offer them to his chum, who immediately clapped them to his own eyes.
"Huh!" grunted Frank a moment later, "squaws along; each cayuse dragging poles on which they heap their lodges, blankets and such; reckon there's no war party about that, Bob."
"I should think not, if what you've told me about the Indians is a fact, Frank. But look here, what d'ye suppose they're doing so far away from their reservation?" and Bob gripped his quirt, which hung, as usual, from his wrist, in cowboy fashion; and with a nervous slash cut off the tops of the rattlesnake weed within reach.
"That's where you've got me, Bob," replied the one who had been brought up on a ranch, and who was supposed to know considerable about the life of the plains; "unless they've just got desperate for a good old hunt, and broke loose. Pretty soon the pony soldiers will come galloping along, round 'em up, and chase the lot back to their quarters. Uncle Sam is kind, and winks at a heap; but he won't stand for the Injuns skipping out just when the notion takes 'em."
They sat there in their saddles a while longer, watching the long procession pass out beyond the low hill, and track along the plain through the scented purple sage.
"Navajos, ain't they?" asked Bob, who, of course, depended on his comrade for all such information, since one Indian was as much like another as two peas to him.
"Sure thing," replied the other, carelessly. "Tell 'em as far as I can glimpse the beggars. And I just reckon now that's old Wolf Killer himself, ridin' at the head of the line, with his gay blanket wrapped around him. Wonder what he'd say if he knew Frank Haywood was here, so far away from the home ranch?" and Frank chuckled as though amused.
"Do you know the old chief, then?" asked Bob.
"Say, do I?" replied Frank, with a laugh. "Remember me telling you how the boys on our place caught a Navajo trying to run away with one of our saddle herds about three years ago, when I was hardly more'n a kid? Well, I chased him with the rest of the outfit, and saw old Hank throw his rope over his shoulders. He snaked the fellow over the ground and through the short buffalo grass like a coyote, 'till he was punished enough; and then my dad made 'em let him go. But you just ought to have seen the way he folded his arms, stared at each of us, and, never saying a single word, walked away. I've often wondered if he didn't mean to come back some day, and try to get his revenge."
"And that was the chief himself?" asked Bob.
"Just who it was," Frank went on. "He'd left the reservation, and got too much fire-water aboard, they said; so he thought the good old days had come back, when a Navajo always tried to get away with any horses he ran across. They say Wolf Killer used to rustle cattle long ago, till Uncle Sam put his hand down heavy on his tribe, and shut the lot up."
"Then, if he has reason to remember everybody connected with Circle Ranch in that way, I reckon it's just as well we don't try to let him know we're here," remarked Bob, uneasily. "We didn't come out on this little picnic for trouble with the reds. There they go, pushing through the sage brush, Frank. So-long, Navajo, and good luck to you on your hunt," waving a hand after the departing string of distant figures.
"Our way lies yonder, along the foot of the mountains," said Frank, as he turned his head to look toward the grim range that stood out boldly against the skyline.
"Yes," observed his companion, as he allowed his black horse his head, once more advancing in a Southerly direction, "and, unless all signs fail, that's Thunder Mountain towering above the rest of the peaks."
"You're right, Bob, that's what it is; and we're going to camp at its foot unless something goes wrong," and as he spoke Frank urged Buckskin on again.
The yellow bronco was a true range pony. He had been taught many of the clever tricks for which his kind are noted. A stranger would have had a hard time keeping his seat on the back of the animal, such was his dislike for unknown parties. He could dance almost as well as a circus horse; and when Frank had tended the saddle herd at night, as horse-wrangler, he was accustomed to depend on Buckskin to give ample warning of trouble, whether in the shape of a storm, a threatened stampede, or the presence of cattle-rustlers.
Both boys were, of course, dressed pretty much as cowboys are when on the ranch; leather "chaps" covering their corduroy trousers; with boots that mounted spurs; flannel shirts; red handkerchiefs knotted around their necks; and with their heads topped by felt hats, such as the men of the range delight in.
Slung to their saddles were a couple of up-to-date guns of the repeating type, which both lads knew how to use at least fairly well. Of course both carried lariats slung from the pommels of their high Mexican saddles. Frank was accustomed to throwing a rope; while Bob, naturally, had much to learn in this particular.
"Say," remarked the latter, who had fallen a trifle behind his comrade, "to see the way we're just loaded down with stuff makes me think of moving day in the old Kentucky mountains. But no use talking, if a fellow wants to be half way comfortable, he's just got to lug all sorts of traps along."
"That's right, Bob," assented the other, laughing. "And that applies in an extra way when he means to be out in the Rockies for perhaps a week."
"No telling what he may run up against there, eh?" queried Bob.
"Well, if it isn't a grizzly, it may be an avalanche, or a cloud-burst," remarked the boy who had spent his whole life in the open.
"Not to speak of Indians, or Mexican rustlers looking for a chance to drop down on some peaceful ranch, and carry off a bunch of long horns; eh, Frank?"
"Sure; and a lot more besides, Bob," was the reply. "But the sun's getting kind of low, you notice."
"In other words, we'd better be looking around for a place to camp, Frank?"
"You've hit the nail on the head," the other replied. "Suppose we hold up here for a bit, and let me take another squint up yonder through the glass."
"Meaning at old Thunder Mountain?" observed Bob, as his eye traveled upward toward the bare crown of the great uplift, that had so long remained a source of mystery to the entire community.
"Yes. Just look at the pinons growing up the sides like tufts, along with the funny looking clumps of stunted cedars. Then you can see the aspens and silver spruce next. And over the whole outfit is a silence that beats the desert itself. Whew! the closer you examine the place the more it impresses you."
Bob accepted the glasses after Frank had used them and focussed them on the slope.
"So that's old Thunder Mountain, is it?" he remarked. "Well, I must say it shows up right well. I've tried to picture the place from all we've heard."
"But you don't feel disappointed, do you?" asked Frank.
"Not a bit, Frank," his companion continued. "I've seen some mountains, even before I came out here to your Rockies; but there's something about this thing that just staggers a fellow. Wow! but we'll sure have our troubles climbing that wild slope."
"Never could make it if it wasn't for the canyons," Frank added. "They all tell me that. Here, let me put the field-glasses away. Half an hour's gallop, and we'll jump off. That ought to bring us to the foot of the slope. Here you go, Buckskin; show us you're not tired after your day's run. Whoop-la!"
Frank brought his hat down on the flank of the horse, accompanying the action with a real cowboy yell. Instantly the spirited steed bounded off, with Bob's Domino close behind, snorting, and giving signs of astonishing animation.
So they sped along, with clanking sounds from the various packages fastened behind the saddles; but after a few minutes both boys gradually drew upon the lines, knowing full well that their mounts had done a fair day's work already; and, besides, there was no possible need of haste.
"How's this for a camping place?" asked Frank, as he suddenly brought Buckskin upon his haunches in a quick stop.
"Suits me first rate," replied his chum, after giving a glance around. "Let's see if I remember all you told me about what a fellow has to look for when he expects to go into camp. Water handy, grass for the horses, wood for a fire, and shelter from a hidden mountain storm. What better could we ask, I'd like to know? Is it a go, Frank?"
For answer the shorter lad jumped from his seat. His first act was to remove the saddle, and then, with a handful of dead grass, rub the sweaty back of the mettlesome animal, as every true son of the plains always does before he thinks of his own comfort.
Next he hobbled the animal, and drove the stake pin, to which the lariat was attached, deeply into the ground. After that the bridle came off; and Buckskin's first natural act was to drop to the ground, and roll over several times.
Bob was following this procedure with Domino. The intelligent animals seemed to understand just what the programme was to be; for after rolling, they walked down to the little watercourse to slake their thirst; and then set about eagerly nibbling the sweet grass that grew all around.
The two chums went about preparing to spend a night under the bright stars, with a readiness that told of long practice. Bob, of course, knew less than his companion about such things, but Frank had often accompanied the cowboys on his father's ranch on their expeditions, and had even spent nights in the company of old Hank, when off on a hunt for fresh meat; so that he knew pretty well what ought to be done to add to their comfort.
It pleased him to show Bob some of the things he had learned. There might be no real reason why he should start a cooking fire in a hole he dug, rather than make a roaring blaze that could be seen a mile away; but Bob was tremendously interested, and would never forget all that he learned.
"Besides," Frank explained, after he had the small fire started, "it is easier for cooking, once you get a bed of red ashes; because in this warm country a fellow doesn't much like to get all heated up, standing over a big blaze."
Bob had, meanwhile, opened some of the bundles. One of these contained a small coffee pot, as well as the frying pan without which camping would be a failure in the minds of most Western boys.
"Look out for rattlers," advised Frank, as his chum went to the spring hole to fill the coffee pot. "They often come to such places in dry season We haven't had rain for so long now, that, when it does come, I expect a regular cloud-burst. That's often the way in this queer country, along the foothills of the Rockies."
Hardly had he spoken than there sounded a sudden and angry whirr, similar to the noise made by a locust, and which Frank knew only too well meant a rattlesnake!
"Hey! take care there, Bob!" shouted Frank, starting up from beside his little cooking fire in something of a panic; for that alarm signal is apt to send the blood bounding through the veins like mad, whenever heard.
"Don't bother!" came the reassuring reply of the unseen Bob, from a point near by; "I think I've got the beggar located, all right. Say, don't he sing though, to beat all creation? He's mad clean through, all right. I'm looking for a stick, so as to knock him on the head."
"Go slow, and keep your eye out for a second one," advised Frank, uneasily; "because they generally hunt in couples. That isn't a measly little prairie rattler either; but a fellow that's come down from Thunder Mountain."
"Nice warm reception for visitors, I should remark," laughed Bob, immediately adding: "there, I've found just the stick I want. Now, old chap, look out for yourself! I'm going to have that rattle of yours to take home, unless you give me the slip."
"No danger of that," remarked Frank; "because a rattler seldom runs away, once he shakes his old box, and gives warning. Hit him just back of the head, and let it be a good smart blow too, so that you break his neck."
Then came a swishing sound, twice repeated. The thrilling rattle immediately subsided.
"Get him?" demanded Frank, ready to take up his task once more, upon receiving a favorable reply from his friend.
"He's squirming some, but helpless," returned Bob, composedly. "I'll cut his head off, so that he can't turn around and jab me while I'm getting that rattle box of his."
Two minutes later he came back into camp, carrying the coffee pot, which he proceeded to place upon the fire Frank had started. The latter noticed that his chum was trembling a little, and could give a shrewd guess that Bob had been more startled than he had thus far admitted.
"Perhaps I'll get used to it in time," Bob remarked, presently; "but it sure does give a fellow a nasty shock to hear that sound burst out close by your feet, knowing as you do what a bite from those fangs means."
"Then it was a narrow squeak, was it?" asked Frank.
"I guess I never want to be closer to a diamond-back than that," Bob admitted, with a shake of his head.
Soon a delightful aroma began to steal through the air in the immediate vicinity of the little camp near the foot of the towering, mysterious mountain; as some bacon sizzled in the pan, and the crushed berry from Java boiled and bubbled most cheerily.
Besides, upon some splinters of wood Frank had thrust small pieces of venison, the last fresh meat they had brought from the ranch. As the heat from the red coals began to turn these to a crisp brown, Bob sniffed the added fragrance in the air after the manner of a hungry range-rider, or a boy with a healthy appetite.
"Seems to be plenty of game around here," he remarked. "I jumped two rabbits near the spring, and they went up the rise, as usual."
"Yes," remarked the cook, "the place looks good for game, and you'd wonder why those Injuns passed it by, only I happen to know. Ten to one there's a deer in that thicket of wild plum over there. And you can just believe an old grizzly wouldn't want a better hang-out than up yonder among the cliffs and crags of the mountain side."
"But to return to our mutton, which after all is antelope meat, when do we start operations? I'm nearly wild, with all these smells, and never a bite. The water just drips from my tongue, I give you my word, Frank."
For answer the other picked up the coffee pot, and set it aside for a minute, to let the contents settle.
"Grub's ready, Bob," he said, laughingly; "and I reckon we'll not bother banging on the frying pan with a big spoon to-night, range fashion. Sit down, and get your pannikin ready for some of this bacon and meat. How does that coffee look?"
"Say, it's got the color, all right, and if it only tastes half as fine as it looks you'll hear no kick coming from me," replied Bob, as he poured his tin cup full of the liquid.
As the boys ate they chatted on various topics, most of which talk had of course some connection with the big cattle ranch they had so recently left.
"I'd give a heap to know if Peg Grant meant business when he said we were riding to a fall if we thought we were the only pebbles on the beach," Bob remarked.
"Oh!" replied Frank, "I reckon he's going to make a try to solve that Thunder Mountain puzzle. But just think of a tenderfoot like Peg let loose on that fierce slope up yonder; will you?"
"Perhaps he's here already," suggested Bob.
"Wouldn't be one bit surprised," Frank continued, readily enough, as though he considered that a foregone conclusion anyway. "He and his cronies had time enough, unless Peg changed his mind. He might be wondering what happened to you, and thinking how the X-bar-X ranch would be safer, in case some of our boys chased after him to give him the tar and feathers he deserves for playing such a mean trick."
"But supposing they did come," said Bob; "Peg and Spanish Joe, and that other treacherous cowboy you told me about; we're pretty apt to meet up with them if we go prowling around here for the next few days."
"Just so, and we'll try to mind our business all the time," remarked Frank; and then his eyes flashed a little as he continued: "but if they try any of their ugly little tricks on us, Bob, they're likely to get hurt."
"I'm with you there, Frank," the other added, shutting his teeth in a determined way. "I can stand a certain amount of fun, and, I hope, take it the right way. Your cow punchers said that when they hazed me, you know. But I certainly do object to any such rough-house business as fastening a poisoned thorn under a fellow's saddle."
"That game has cost more than a few people their lives," Frank declared vehemently. "Cowmen draw the line at it. You noticed how angry old Hank became when he heard about that same thing. But your horse seems to be getting on all right, Bob."
"Sure he does. That ointment made by old Hank's like magic. Domino won't suffer much from that jab. But that was a bully good supper all right, and I don't care how soon we repeat it," he concluded with a laugh.
Finally both lads lay down to secure such rest as they needed after a long and tiresome day.
The drowsy chirp of crickets, and shrill voices of katydids in the lush grass near by, told of the summer night. Many times had Frank listened to this same chorus as he lay in his blanket on the open prairie, playing the part of night-wrangler to the herd of saddle horses belonging to the round-up party of cow-punchers.
He could hear some lurking rabbit slinking through the hazel bushes over at one side. Somewhere off on the level, where the sage grew so heavily, there must have been a prairie dog village; for the sound of the peculiar barking of these queer little animals frequently floated to his ears as the breeze changed.
The two horses were still feeding at the time Frank dropped off into a sound and refreshing sleep, but doubtless they would soon lie down. Bob was already breathing heavily, which would indicate that he had passed beyond the open door to slumber-land.
The minutes passed, and several hours must have gone.
Frank was dreaming of the excitement attending some of the many dashing gallops he had lately enjoyed in company with his chum, looking up stray cattle, helping to brand mavericks, watching the cowmen mill stampeding herds, or chasing fleet-footed antelopes just to give the horses a run.
He was suddenly aroused by a strange sound that seemed to cause the very earth under him to tremble. The trample of a thousand hoofs would make such a noise; if one of those old-time mighty herds of bison could have come back to earth again; or a stampede of an immense herd of long-horns might cause a similar vibration.
But Frank Haywood knew that neither of these explanations could be the true one, even as he thus sat upright on his blanket to listen. The ominous, growling, grumbling noise was more in the nature of approaching thunder, just as though one of those furious summer storms, tropical in their nature, and often encountered in this country where plains and mountains sharply meet, had crept upon them as they calmly slept.
And yet, strange to say, neither of the two boys jumped quickly to their feet in wild dismay, seeking to prepare for the rain that might soon burst upon them. On the contrary they continued to sit there, straining their ears to catch the rumbling reverberations that kept coming, with little respites between.
"Say, now, what d'ye think of that, Bob?" asked Frank, when silence again held sway for a brief period. "Nary a cloud as big as your hand in the sky; and yet all that grumbling oozing out of old Thunder Mountain! Looks like we might have the biggest job of our lives finding out the secret of that pile of rocks. There she starts in again, harder than ever. Listen, Bob, for all you're worth!"
"It's stopped again!" remarked Bob, after possibly five minutes had passed, during which time the ominous rumbling, accompanied by earth tremors, had kept up, now rising to a furious stage, and then almost dying away.
Frank gave a big sigh.
"It sure has," he admitted; "and I don't wonder now, after I've heard the racket with my own ears, that the reds for a hundred years back have always declared the Great Manitou lived in Thunder Mountain, and every little while let them hear his awful voice."
"Then this thing has been going on forever, has it?" asked Bob.
"The Navajos say so; though even they admit that, of late, it's got a brand new kink to the growl," Frank answered. "They believe it's sure unlucky for any brave to be caught near the mountain after dark, and especially when Manitou scolds. You see, that accounts for the hurry of that hunting party to climb out before sunset."
"Yes," Bob went on. "And now I understand what you said about the Indians never hunting near Thunder Mountain. Perhaps they believe all the game that hides along the slopes, and in the deep gullies, belongs to the Great Spirit, and that he'll punish any warrior bold enough to try and get a line on it. But see here, Frank, do white men—cowboys, prospectors, and the like—believe this mountain is haunted?"
"Heaps of 'em do, and that's a fact," replied the other, chuckling. "I've heard some of our cowpunchers talking about it more'n a few times; and you remember how old Hank took it when we told him what we had in mind?"
"They're a superstitious lot, as a whole, I take it," Bob ventured. "Now, as for me, I never could believe in ghosts and all that sort of thing. If there ever came a time when something faced me that I couldn't understand, I just set my teeth together and vowed I'd never rest easy till I had found out what it meant."
"Same here, Bob; and that's why I just jumped at the chance to beat Peg out in his game. The funny part about it is why I never thought of this racket before. But perhaps that was because I didn't have a chum to stand back of me."
"None of the boys on the ranch would go with you, then?" asked Bob.
"I should say not! Even old Hank would balk at that, and he's never been afraid of thing that flies, runs or crawls. It was old Hank who taught me all I know about range life. He showed me how to shoot, throw a rope, and do heaps of other things a prairie boy ought to know. Hank thinks lots of me, and honest now, Bob, that gruff old fellow would willingly lay down his life for me."
"I reckon he would," assented the other, readily enough.
"But Hank's a rank believer in the Injun story of the mountain, and would never come here of his own accord; but to keep an eye on me, and, stand between me and danger, he'd just crawl down the crater of a live volcano."
"Seems like the show might be over for tonight," Bob suggested.
"The row has stopped, sure enough," Frank remarked, looking up at the dimly-seen outlines of the far-away crest of the rocky elevation, where it stood out against the starry heavens.
"You don't believe, then, that there could have been some kind of storm up there; do you?" questioned Bob.
"Well, it's sure a great puzzle," replied his chum, with a long breath. "My eyes are reckoned prime, but I can't glimpse any sign of a cloud that would bring out all that noise. A mystery it's been these many years; and if so be we can learn the cause for all that queer roaring that shakes the earth, we'll be doing more'n anyone else has ever done in the past."
"That's what we're here for, if Peg gives us half a chance," remarked Bob, with the healthy assurance of youth. "And as neither of us takes any stock in the fairy story about the Manitou's anger, we ought to stand some chance of locating the thing; or 'bust the b'iler trying' as old Hank would say."
Frank had crawled out of his blanket, and stood erect.
"What's on?" asked his camp-mate, presently, noticing that he was holding up his hand, after wetting his finger, a method much in vogue when one wished to learn the direction of the passing air currents.
"Southeast; and blowing strong a bit ago up there on the mountain, I reckon," Frank remarked. "You notice we happen to be sheltered more or less down here, when she comes out of that same quarter?"
"Meaning the wind," Bob remarked. "Yes, you're right, Frank. But what has that got to do with the measly old grumble of the mountain, tell me?"
"Huh! I don't know that it's going to have anything to do with it," came the answer; "but we want to know every little point as we go on. And Bob, just remember that the wind was coming out of the Southeast; and a clear sky overhead!"
"But look here, Frank, you've heard your dad talk about this Thunder Mountain business, I take it?"
"Well, now, I reckon I have, heaps of times; but then you know, he isn't much on bothering about things that don't concern him. Thinks he's got his hands full, looking after the stock, keeping tabs on the doings of those rascally Mexican rustlers, that have been running off batches of cattle every little while; and fighting that big syndicate of Eastern capitalists, headed by the millionaire, Mr. Grant, Peg's father, that wants to throw all the Southwestern ranches into a close trust."
"But what I wanted to remark is this: you must have heard him give an opinion about this thunder sound?" Bob persisted in saying.
"Oh! he thinks the same as several gentlemen did who came out here a few years ago on some business. They declared that once, hundreds of years ago, perhaps, old Thunder Mountain must have been a volcano; and that it still grumbles now and then, as the fires away down in the earth begin to kick up some of their old monkeyshines."
"Yes, I heard one man say that," laughed Bob. "He declared that there's going to be the biggest rumpus some fine day, when the fires inside get to going out of bounds. Then the whole cap of the mountain will go flying into a million pieces; and good-bye to any unlucky cow-puncher caught napping near this place."
"Well," remarked Frank, as he prepared to settle down again into his snug blanket, "I reckon we're not going to be scared away by a little thing like that growl. Unless we hit a snag, or Peg Grant and his guides break up our game, a few days ought to see us heading back to Circle Ranch with a story calculated to make the boys sit up and take notice; or else——"
"Just pull up right there, Frank," interrupted his chum, with a laugh. "There's nothing going to happen to knock us out. If that same Peg comes around, making a nuisance of himself, why, he's due for a nice little surprise, mark me. Besides that; what could there be to make trouble?"
"Oh, I'm not bothering my head over it, Bob," declared the other, as he dropped into the nest he had made in his blanket. "But say, did you take notice of the way our horses acted while that thing was going on?"
"Just what I did," the other replied. "They must have been trembling all over. I could hear your Buckskin snorting to beat the band, and pawing just like he does when he's worried. Reckon they didn't know what to make of it, either, seeing that there's nary a sign of a storm cloud around. But both horses have quieted down again. They think all danger of a howler has passed away."
Frank made no reply. He was already getting ready to resume his interrupted nap; and Bob lost no time in following his example, both confident that in the alert Buckskin they had a sentry capable of giving ample warning should peril threaten.
Once more Frank composed himself for sleep. The many noises of the night, which had seemed to cease while that mysterious rumbling was going on in the heart of the lofty mountain, had again resumed sway. The hum of insects; the melancholy hooting of the lonely owl, in some willow or cottonwood tree near the base of the mountain; the far-off howl of the prairie wolf; or the more discordant voice of the skulking coyote—all these things were as familiar music in the ears of the boy whose cradle had been the rich black earth of the grazing country ever since he was old enough to remember anything.
They all did their share in lulling him to sleep. And, no doubt in dreams, he was once more galloping across the wide prairie on the back of his mount, his nostrils filled with the life-giving air of the sage-covered level.
Frank slept, he never knew just how long.
This time it was not the rumbling sound and the fearful vibration of the ground that aroused the two saddle boys; but a far different cause.
When Bob sat up he found his comrade already erect, and apparently listening as though keenly alive to some approaching peril.
"Buckskin's uneasy, you see," remarked Frank in a whisper; "he's pawing the ground and snorting as he always does when he scents danger."
As he said this, Frank dropped back again, and seemed to place his ear to the ground, a trick known and practiced among the Indians from the days of the early pioneers along the Ohio down to the present time; since sound travels much better along the earth than through the air—at least, in so far as the human ear, unaided by wireless telegraph apparatus, is concerned.
"A bunch of horses coming out of the Northwest!" announced the prairie boy, almost immediately; "and we can't get our nags muzzled any too soon, Bob."
Apparently the other lad had been coached as to what this meant. He sprang to his feet, snatching up his blanket as he did so. Together they were off on the jump toward the spot where their animals had been staked out at the end of the lariats.
Arriving at the pins which had been driven into the ground each boy sought to clutch the rope that held his restlessly moving horse; and hand over hand, they moved up on the animals, the blankets thrown over their shoulders meanwhile.
A few low-spoken words served to partly soothe Buckskin and his black mate; then the blankets were arranged about their heads, and secured in such fashion that no unlucky snort or whinny might betray their presence to those who passed by.
At a word from his master the well trained Buckskin doubled up, and lay down on the ground. Most cowboy ponies are taught to do this trick by their masters, and it is in common use; so that the punchers believe it is a poor animal that has not learned to roll over and play dead on occasion.
Bob, too, managed to induce his mount to do the same thing; but to make it absolutely certain that no unwise flounder on the part of Domino might betray them, he sat upon the horse's head, soothing him by little pats on his glossy hide.
"I hear 'em coming," announced Frank, presently.
The sounds reached him against the wind, so that it was quite natural to believe the approaching horses must by now be very close. There was a confused pounding that could only spring from a large body of animals. The trained ear of Frank caught a significance in the clash of hoofs that told him much more than Bob was able to make out.
"All horses, Bob," he whispered across the little gap that separated him from his chum; "and two thirds of 'em running free, without saddles or riders. Lie low, now, and see if you can glimpse 'em as they go past."
"Won't they be apt to run over us?" asked Bob, a bit nervously.
"Nixy. I looked out to pick a place they'd be apt to avoid. They'll brush past a little further to the south," and Frank ended his words with a hiss of warning.
The pounding of many hoofs continued. Frank, straining his eyes, believed he was now able to make out a confused moving mass at some little distance away, heading directly toward the foot of Thunder Mountain.
As the starlight was so vague he could not make out more than that here and there a figure was mounted on a galloping horse, with several unridden animals trailing along behind, as though led by ropes.
The little caravan passed quickly. Already they were vanishing in the deeper shadows lying closer to the base of the mountain that towered aloft several thousand feet.
Still the two boys continued to sit there, guarding their horses; although all danger of discovery seemed absolutely past.
"Whew!" exclaimed Bob, presently, as the sound of retreating hoofs began to die away; "what d'ye think of that, eh, Frank?"
"Indians?" queried the Kentucky boy, eagerly.
"Well," replied his chum, "not so's you could notice. Say, now, you didn't see any feathers on their heads, did you? And I sure heard the fellow nearest us say something that only a white man would remark, when his horse stepped into a hole, and almost threw him over its head."
"Cow punchers; or perhaps rustlers?" continued Bob, anxious to know.
"What would cowmen be doing away off here, tell me that, Bob? And lugging along a bunch of extra mounts, too, in the bargain? No, I rather think, Bob, that those fellows must have some of Mendoza's cattle rustlers. And they've been making a dandy raid on some ranch's saddle herd; or I miss my guess."
"Perhaps the Circle outfit had gotten careless," suggested Bob.
"I sure hope not, for the boys have had plenty of warning; and I reckon Bart Heminway is some too good an overseer to permit such a raid. I'd rather believe it was the X-bar-X outfit that has gone and got nipped this time. But stop and think Bob; what d'ye expect takes these cattle-rustlers over this way right now, headed straight for the canyons of Thunder Mountain?"
"Oh, I see what you mean!" exclaimed the taller lad, immediately. "Perhaps the secret hiding place of Mendoza and his crowd of cattle thieves may be somewhere around this same old rock pile. It'd be just like the tricky rustler to have a hide-out where nobody else ever came!"
"Now, why didn't somebody ever think of that before?" ejaculated Frank, in a tone of mingled surprise and disgust.
"Looks easy, doesn't it, after we've run across a clue?" admitted Bob, laughing softly. "You remember what they said about discovering America, after Columbus did it. But supposing this thingdoesturn out to be true; how's it going to affect our little business, Frank? Oh! say, I wonder if that crowd can have anything to do with the rumbling of the mountain?"
Frank laughed heartily at the suggestion.
"Well," he remarked, "they're a pretty tough lot, all right; but even such a bad bunch could hardly get enough hot air together to make a mountain shake and groan like that. Besides, don't you see, Bob, they must have been out yonder, riding this way with their stolen horses, when that little circus came off."
"But one thing is sure," the other went on, sturdily; "they don't seem to take any stock in that notion about a volcano, because, as we saw, they headed straight for Thunder Mountain. That gives it away; they're so used to the row that they don't pay any attention to it any longer."
"Correct!" echoed Frank, as though his mind was made up.
"Do we need to hold the horses down any longer?" asked Bob, who could feel that Domino was becoming very restless under his enforced silence.
"I reckon not," replied the other, at the same time taking the blanket from Buckskin's head; whereupon the animal, recognizing this as a sign to rise, quickly gained his feet and shook himself.
"It's back to the blankets again for another nap," remarked Bob, when he, too, had seen his animal regain an upright position. "Wonder what's next on the programme for us. Twice, now, we've been waked up; and I don't know whether it's really worth while trying to get any more sleep to-night. It isn't a great ways from dawn, is it, Frank?"
The other cast a quick look up at the stars. Accustomed to reading these heavenly sign posts of the night, he was able, from their positions, to give a pretty fair guess as to the hour; just as the sun served him in place of a watch during the day.
"Three hours yet to dawn, Bob; no use staying up all that time," he said, presently. "We expect to be on the move again at peep of day; because, after what's happened, it'll be wise for us to get off the level here before broad daylight comes along. There might be curious eyes on the watch up yonder, on Thunder Mountain; and that, you see, would just spell trouble for our crowd."
"Whew! things are thickening, for a fact!" exclaimed Bob.
"I was only thinking," Frank continued, "whether we ought to try and get word back to the ranch about our discovery. If they knew Mendoza and his rustlers were hiding somewhere about this place they'd comb the whole mountain range so they could run him to earth. He's been the pest of the border too long now, and something's just got to be done to chase him back where he belongs, south of the Rio Grande."
"But you don't want to go back just yet, do you, Frank?" asked Bob, uneasily.
"I'm ready to do what you say, though I'd like to stay," came the prompt answer.
"Then I say, let's stick it out," declared Bob, with animation. "It might turn out to be a false alarm, after all; and we'd feel pretty cheap to bring all the boys along, and then not be able to show 'em any game. No, I say it'll be time enough to go after 'em, when we make dead sure!"
"That settles it, then," remarked Frank, with a little laugh, as though pleased to learn that his saddle chum looked at the matter in such a sensible light.
This time, after they had lain down in their blankets, there was no further alarm. Frank, from long habits of early rising on the range, awakened just as the first faint streaks of dawn began to show in the eastern horizon.
It required but a touch to arouse Bob; and saddling up, with packs in place, the boys soon left the scene of their night bivouac, heading toward the heavy growth of timber directly at the foot of the mountain.
The early morning mists concealed their movements until they had entered among the timber; when they left they were safe from any suspicious eye, should the bold Mexican rustler have posted any watcher upon the side of the mountain.
Again did the saddle boys build a small fire in a hole, over which they proceeded to cook their breakfast; while the horses cropped the grass near by, secured by the ever useful lariats, or riatas.
"There's where this leads into a big gully," remarked Bob, later on, pointing as he spoke to where the ground became broken.
"Yes," Frank went on, thoughtfully, "and the chances are ten to one that it changes into a regular canyon, where the water rushes down whenever they have one of those gushers, or cloud bursts, that come along once in a while around here. Now, I wonder if those riders hit it up this way?"
He jumped to his feet as he said this. Passing back and forth, Frank seemed to be examining the ground, marking the stepping stones of the mountain.
"Signs aplenty around here," he remarked. "Wish old Hank was along to read 'em. I reckon I can tell what they stand for, though."
"Then they went on up that canyon, you believe?" asked Bob.
"Reckon there isn't any doubt about that part of it," chuckled Frank; "though just where that same canyon leads I can't say. P'raps it may be a short-cut across the big range here, leading to the prairie on the other side. P'raps it doesn't go anywhere, but just leads to a blind hole that I've heard prospectors call acul de sac. Anyhow, we ought to find out, Bob."
"Theyknew all right," remarked the other, positively. "Wouldn't get any riders going up there in the dark, unless they were mighty familiar with every foot of the way. That's my idea, Frank."
"And I reckon it's the true one," asserted the other. "They know this place as well as I do all around old Circle Ranch."
"There's the sun coming up; and perhaps we'd better be getting a move on about now?" suggested Bob.
"Wait!"
Something in the tone which his saddle chum used caused Bob to turn his head, and look out toward the plain.
"Huh! what does that mean?" he ejaculated. "A single rider heading this way; and he seems to be leading a burro loaded with supplies. Must be a bold prospector, bound to look into the secrets of Thunder Mountain as we're bent on doing; only he hunts for gold, while we're just bent on finding things out."
"But look now," Frank said a little later, as the other came closer. "Don't you see that it's only a little Mexican boy on that bag of bones of a horse? Tell you what, Bob, he must have been sent to town for fresh supplies by some party of gold hunters located right now over the range."
"Yes, and how do we know but what this Mexican boy is hooked up with that Mendoza crowd?" asked the other, seriously. "They might send him off for grub, and such things as they happen to need. And he pays for it with money they get from selling stolen cattle and horses! Nobody would suspect him, Frank, and try to follow. I hope our horses don't give us away now. I'd like to see what that little fellow does."
The boy indeed looked weary as he drew closer, leading his tired burro, upon which a fair-sized load was strapped and roped.
"Get down, Bob," said Frank. "He hasn't glimpsed us, and, luckily enough, our horses are feeding out of sight just now. Doesn't he look sleepy and tuckered out though? See him nodding in his saddle, poor little runt! Oh! what's that moving there among those rocks just ahead?"
"Perhaps it may be one of the rustlers coming down to interview him," said Bob.
"Hist!" Frank uttered almost in his chum's ear as he craned his own neck in order to see better.
The small boy on the tired broncho, and leading the patient burro, kept on steadily advancing, apparently allowing his animal to follow its nose, as though it knew the way fairly well from having passed along it before.
"Look! look!" ejaculated Frank suddenly, jumping to his feet. "Great guns! Bob, would you see what is coming out from among those loose rocks there? A great big grizzly bear; and making straight for the pack mule, sniffing the air as if he smelled grub! There, the horse has scented him. See him rear up, will you? Oh! he's gone and done it, as sure as you live—thrown the boy over his head! And the poor burro is caught fast, with his leading rope held in a crotch of the rocks. The boy will be killed if ever he meets up with that monster! Quick! We must do something to save him, Bob, but whatever shall it be?" and Frank leaped to his feet.