The top of the tree sprang up with such force, when relieved of the weight of the fat boy, that Tad Butler lost his hold and was catapulted to the ground, which he struck with a force that made his bones ache.
The two Pony Rider Boys sat up rubbing themselves and looking into each others' faces.
"Well, what do you think of that?" jeered Stacy Brown.
"I think we got a fine tumble," replied Tad, grinning.
"And I think something else, too."
"Yes, we've made a discovery!"
"A great discovery," breathed Stacy tensely.
"I think so, but that remains to be seen. Who would have thought it? But get away from here! We may have disturbed some one."
The lads quickly scrambled up and, skulking into the bushes, crouched down, watching the roots of the tree, almost expecting them to rise into the air again. Nothing of the sort happened. The birds were singing in the trees, the sun was shining brightly, the heat was intense.
"I'm going to investigate," declared Tad.
"Maybe we've discovered another gold mine, or perhaps a German dugout," suggested Chunky.
"Perhaps, but not in the way you think."
"How do you mean?"
"Wait until we investigate. There may be more to this than either of us think. I wonder if we can weight that tree down so the roots will stay up in the air?"
"I saw some rocks there near the top. Perhaps we can make them stay on so the top will be held down."
"You get up on the tree again and I'll pass the rocks up to you. Place them so they won't slide off. I don't want to get crushed by them falling on me."
"Neither do I want to get thrown off again. I'm black and blue all over, right this minute."
"I think I must be by the feel of my skin. Hurry!"
Stacy ran back to the roots, once more clambering to the trunk, along which he ran clear to the outer end. Tad was ready with a heavy, flat rock which he carefully raised by main strength.
"Now, don't you dare let that drop on me or I'll be mashed flat, Stacy Brown."
"I---I won't let it d-d-rop un---unless I---I fall off."
The rock nearly got away from the fat boy. Butler leaped back out of the way, but Stacy recovered himself in time and after some effort succeeded in placing the rock in the limbs of the tree.
"Fits as if it had been here before," declared Chunky.
"Perhaps it has. We shall see. Are you ready?"
"Yep."
"Here's another."
By the time the third stone had been put in place the top of the tree began to settle. The fourth rock brought the tree down to the ground, exposing the opening in the rocks once more.
"Hurrah!"
"Keep still. Don't move till I get enough up there to equalize your weight. Then you may come down."
The remaining stones were quickly laid in place. Tad motioned for Chunky to descend. The fat boy leaped down. The tree top remained on the ground leaving a wide opening in the rocks.
"Now, Chunky, keep your nerve. You may need it."
"What are you going to do?"
"I'm going in there. I think perhaps it might be the wiser plan for you to remain out here and keep watch."
"No, sir, I guess not! I've helped discover that hole and I'm going to reap my reward by exploring the inside."
"Come along then. It is taking long chances, but I guess the tree is safe unless some one should come along and trip the stones. Then we would be in a fine fix, shouldn't we?"
"I reckon we would. We wouldn't be getting out of that hole, right smart, should we, Tad?"
"I guess not. We should be buried alive."
"Still, there may be some other opening to the place. We will take a chance. Got your matches?"
"Yes."
"Then you light a match when we get inside. I'll have my revolver ready in case there is anything in there."
Taking a final glance about, Tad moved toward the opening in the rocks with brisk step. Chunky was trotting along behind him, the fat boy full of importance over the discovery they had made. At the opening they paused, glancing apprehensively at the great roots towering above them. Were the butt of that giant tree to settle down now, it would crush them.
The boys stepped inside. They could see but a few feet ahead of them, but saw that they were in a huge crevice in the rocks, a sort of cave formed by the splitting apart of the rocks themselves, perhaps from some long past earthquake disturbance.
"Light a match, Stacy."
The fat boy did so.
"There have been horses in here," announced Tad.
"Yes, I guess there have, but there aren't any here now."
"Fortunately for us."
The air was cool, though a little damp in the cave. To this the boys gave no heed. They had more important matters on hand than observing the atmosphere of the place. The cave they found was much larger than they had had any idea of. In places the roof was all of ten feet high. But as they penetrated further in, moving cautiously, lighting the way with every step, the walls sloped toward the back, approaching nearer to the floor.
Except for the light from the matches, the boys were in darkness, so that they were not able to observe that the opening to the cave had closed. A strong breeze, swaying the upper limbs of the tree, had dislodged the stones and allowed the roots to slip quietly into place again. The boys, without knowing it, were prisoners.
"You aren't throwing your matches on the floor, are you?" demanded Tad turning sharply.
"Yes, why not?"
"Show me a light here," commanded Tad going down on his knees and gathering up all the burnt matches he could find. "That is a fine trail you are leaving. Why, were any one to come in here, he would discover instantly that strangers had been here."
"I---I never thought of that," stammered Chunky.
"We must think of everything. Our very lives may depend on our doing so."
"Wha---what do you mean, Tad?"
"Don't you understand yet?"
"I---I guess I begin to. Some---somebody's been here."
"Yes. It is my opinion that the very men Captain McKay is looking for have been here. Come, we must be quick! We are likely to be interrupted at any time, though I hardly think any of them would come here in the daytime."
The boys were obliged to stoop in order to continue their explorations further. After creeping under the low-hanging rock they found that they were able to stand erect once more. Then they discovered something else. There were bales piled on top of one another, packs securely tied lying about, guns, rugs, in fact a miscellaneous assortment of goods which the boys believed to be of great value. In one corner stood a chest securely padlocked. It was a rough chest, bound with iron bands that looked as if they might have been used on cotton bales.
"Well, we have made a discovery, Stacy Brown!" breathed Tad.
"We have," agreed the fat boy, his eyes growing large with wonder. "What do you suppose is in that chest?"
"I don't know."
"Let's open it," suggested Stacy eagerly.
Tad shook his head.
"In the first place we have no business to do anything of the sort. In the second place I don't want to stay here much longer. We had better be getting back to camp as quickly as we can. Of course we can't do anything until Captain McKay returns, but the more quickly we get away from here the better it will be for us."
"I---I'm scared. Aren't you?" stammered the fat boy apprehensively.
"No, I am not scared, but I realize that we are in danger every minute we stay here. Those men wouldn't trifle with us, were they to catch us. Do you know what they would do to us if they caught us here, Chunky?"
"Nu---nu---no."
"They would fill us full of lead, that's what they would do. Light another match while I look into this niche. Then we will be making tracks for the outside."
Tad was back by Stacy's side a moment later. He motioned that they were to go back. The boys started briskly for the opening. The instant they had crawled out into the outer chamber they realized that all was not as it should be. At first they did not understand what had occurred.
Tad was the first to make the discovery of what had occurred.
"We're caught!" he cried.
"H---ho---how?"
"The tree has closed the opening to the cave. Now we are in a nice pickle."
Stacy was speechless. He held a burning match in his hand until the match burned up to his finger, whereat Chunky dropped the match with an exclamation.
"I---I'll tell you what let's do. Let's dig through the roots. We can do it. Come on."
Tad laid a restraining hand on the fat boy's arm.
"We won't do that just yet. This may have been an accident. Those stones may have slipped off. I am inclined to think that is what has happened. If so, we don't want to leave any clues---"
"I'd rather leave clues than to leave my dead body in here," wailed Chunky.
"Buck up! Don't show a yellow streak, Chunky!" commanded Tad sharply.
"I'm not yellow. But I know enough to know when I've got enough. I know I've got enough of this bandit-chasing business. I ought to have known better than to go out with you. They think I can't keep out of trouble. I can keep out of trouble all right if other folks don't lead me into it. Now see what a fix you've got me into, Tad Butler!"
"It strikes me that I am in the same fix. But we're going to get out of it, Stacy---"
"Yes, but how?"
"I don't know, but I'll find a way."
"Why, we'll starve to death in here. They'll find our bones here a few years from now and they'll wonder---I wish I had something to eat."
"Tighten your belt. Remember, whatever occurs, you are to leave your revolver in its holster. Don't you dare to draw it unless I tell you to. One little slip might be the death of us. For once in your life be prudent."
"I'll be prudent, but I wish I had a sandwich. Have you looked to see if there's anything to eat in this hole?"
"No, I have something of more importance than food to think about at present."
Tad struck a match, taking a long, careful look about the outer chamber of the cave. He saw nothing to encourage him. Rocks everywhere, with here and there a discolored spot where tiny streams had trickled through, perhaps during a heavy rainstorm.
Tad was thinking with all his might, trying to devise some plan by which they might protect themselves in case they were surprised by the return of the bandits, which he did not think would occur before night, even if then. He reasoned that the bandits were far away else the Rangers would not have gone on a long journey in search of them. That meant that the bandits would not be likely to return until matters had quieted down and the Rangers had left the locality.
"I am afraid we are in here for a long stay, old chap," Butler said finally.
"Another case of being buried alive, eh?" questioned Stacy. "I told you so. I always am right. But I wasn't when I trusted myself to you. You can get into more trouble, and faster than---"
"At least I don't try to shave the professor with my revolver," retorted Tad sharply. "Hark! What was that?"
"I---I didn't hear anything."
"Sh-h-h!" Tad gripped the arm of his companion. Stacy repressed an "ouch" with some difficulty. The two lads stood listening.
Particles of dirt were rattling from the roots of the fallen tree, sounding like hailstones as they fell to the rocks in the cave. Then a faint ray of light appeared under the bottom of the mass of roots.
"Somebody is coming," whispered Tad. "Stand perfectly still until I tell you to move."
"They can't see us at once. Don't make a sound on your life."
"Wha---what are you going to do?" whispered Stacy, his teeth chattering audibly.
"Duck, if I get half a chance. But I don't think I shall. There it goes!"
The great mass of roots rose clear of the ground, exposing the full height of the opening, and the eyes of the two Pony Rider Boys grew large at what they beheld there in the framed circle of light,