JOE’Sfirst impulse was to get to his feet and utter an exclamation of alarm. But he knew that this sudden movement might cause the creature, whatever it was, to rush at him.
His rifle lay at his side for just such an emergency as this. Thankfully Joe raised the gun, took aim, and fired between those two lights, which had now taken the form of eyes.
Bang! The shot broke the stillness of the night and sent Bob and Dr. Rander scurrying over to their friend. They had been on the opposite side of the fire and had not noticed Joe’s movements.
“What is it?” Bob was all excitement.
“Don’t know,” his friend replied. “Let’s see.”
The sound of the gun had not been followed by any other noise. Evidently Joe’s aim had been true, killing the creature instantly.
Bob produced a flashlight, which he turned in the direction in which his friend had fired.
“Why—it’s another snake!” exclaimed Dr. Rander. “A bola. It isn’t poisonous, but it is a good thing you got it. There is no way of knowing what it might have been.”
With the aid of the flashlight they examined the reptile closely. Its head was almost shot off, making it useless as a specimen.
“I’d like to have it for Dad and the other naturalists,” remarked Bob. “But as it is, guess it’s no good for anything.”
“You should have been more careful in shooting it,” teased Dr. Rander. “Now if you had aimed at its body instead of its head——”
Joe smiled.
“A snake has eyes in only one place,” he said laughingly, “and the eyes are the only part of it you can see at night. Now if this fellow had worn a badge to signify that he was a member of the Royal Order of Andean Reptiles, maybe the fire shining on it would have given me a good place to take aim at.”
“Probably wouldn’t bother with him anyway,” said Bob. “After all, we’re out to find the treasure.”
Nothing happened that night to disturb their slumber. They awoke the next morning eager to continue the journey.
“Today we should come to the big secret,”Dr. Rander told them during breakfast. “If all goes well, we should get there this afternoon.”
Bob was restless.
“Let’s hurry and get going,” he urged, untying the mules.
Farther over the rocky trail the three adventurers trudged, keeping a sharp lookout for anything unusual.
Always in the distance were massive snow-clad peaks, which on this morning were enshrouded in a heavy mist. Usually they were plainly visible, especially through the high-powered binoculars that were carried by Joe.
Gradually the path spiraled down the steep slope until it passed through a narrow valley, which was green with a variety of luxuriant vegetation. So dense were the plants that they almost formed a jungle.
“Look at this,” cried Bob, moving over to a vine that was laden with large red berries. “Wonder if they’re good to eat?”
“Yes.” The old man had broken off a branch and was eagerly partaking of the fruit. “They are wild cherries, or tomatoes, as some call them. There is nothing better for taste.”
“Right you are!” agreed Joe, after he had eaten several of the berries. “They’re fine!”
They picked a sackful of the fruit to have at the noon meal. Then they resumed the journey.
At places the trail was overgrown with weeds and grass, making it difficult to follow it. But Dr. Rander had been through this region before and did not hesitate long in picking out the right branch.
“I don’t see how you can remember the way,” Joe told him, when he had pointed out one of three branches, each of which was almost parallel to the others.
The old man laughed.
“I can’t afford to forget,” he said. “All that treasure is something that is worth too much to be forgetting where it is. If it should happen, though, that I should get turned around, I have a rough sketch map of this region that I made at the very start.”
On the other side of the valley was a steep slope that was entirely devoid of vegetation. Look about as the youths did, they could see no path. They were beginning to wonder when Dr. Rander broke the silence.
“From here there is no trail,” he explained. “We’ll have to cut our way through the hard places and climb over large rocks. It won’t be easy, but we will be rewarded.”
“No trail, huh?” thought Bob. “Here’s where the fun begins.”
It was far from fun, in the usual sense of the word. The three labored over short, steep elevations, rocky precipices, narrow ridges, pulling the sure-footed mules behind them. At last, when they finally reached a high ledge, they sat down to get their breath.
“Whew!” gasped Joe, wiping the perspiration from his brow. “I don’t want much of that. Wonder how old Dr. Rander stands up under such a strain?”
“Hardened to it, I suppose,” was Bob’s reply. “Since he left college he’s been nothing else but an explorer.”
The old man had been at the back of the line, attending to the last pack animal. There was a smile on his face as he approached his young friends.
“We’ve made unusually good time,” he said, sitting down beside them, “and we can afford a rest.”
“We earned it, all right,” came from Joe. “How much more of this is there?”
“A long stretch,” Dr. Rander responded. “Several miles, to say the least. Of course,” he added, “it would not be long if we could go in a straight line. But over mountains and around cliffs the going is much different.”
“I’ll say it is!” Joe was still panting from the difficult climb. The high altitude required an unusual amount of wind.
Fifteen minutes later they were ready to continue. The mules had been coaxed ahead over the dangerous ledge.
“Getting darker,” observed Bob Holton. “Wonder if it’s going to rain?”
Dr. Rander looked up anxiously. Sure enough, heavy clouds were forming above the mountain tops, hiding the sun from view.
“It would not be well for us to be caught in a storm here,” the old explorer said. “We must seek shelter somewhere. It certainly looks as if a storm will be upon us before long.”
They looked about for some place of refuge, such as a cave or overhanging rock. But luck was not with them that day. They had searched an hour under a sky that was rapidly becoming darker when suddenly a terrific hailstorm struck them.
“Quick!” gasped Joe, who was almost frantic. “We must find some place!”
“We’re not finding it,” returned his chum, who was taking the danger more lightly. “And I guess there’s nothing we can do but stay out here in the open and endure it.”
But a few minutes later Bob had become as serious as his friend. Hail as large as marbles wasfalling with a terrible velocity, striking the explorers’ faces dangerously. One lump caught Joe squarely on the nose, causing him to utter a cry of pain.
“This is awful!” he moaned, holding his hand in front of his eyes.
How long the storm would last they had not the faintest idea. Even Dr. Rander could express no opinion.
Doggedly they fought off the hail, which bruised and cut their faces and bodies. They wondered how the mules were standing it. Could the animals endure the terrific onslaught? Or would they become panic-stricken and plunge off the steep cliff?
After what seemed like hours, the hailstorm suddenly subsided and the sky began to lighten. Ten minutes later the surrounding mountains bore no evidence of the disturbance.
With the adventurers, however, it was a different matter. Their faces were cut in many places, and their clothing was torn. A more miserable-looking trio could hardly have been found.
“Get out the ointment,” directed Bob. “We’ll sure need plenty of it.”
“The mules came through all right,” observed Dr. Rander. “Cut and bruised, but nothing more.”
“It’s funny,” began Joe, looking up at the sun, which was now in full view. “That was a veryqueer storm. It came quickly and ended the same way.”
“Hailstorms are rather common in this part,” explained the old man, getting out a box of antiseptics and first-aid remedies.
Their numerous wounds were treated with a soothing salve. Then, after looking over the mules, they moved on around the mountainside.
At a huge notch in the rocky slope they stopped to examine a curious formation that puzzled them. It was a long sloping slide, running gradually down the mountainside. From all appearances it was as smooth as glass.
“I don’t know whether this is natural or man-made,” said Dr. Rander. “I never have been able to find out. But,” he went on, “what concerns us is that we’ll have to slide down to the foot of the mountain.”
“What!” Bob’s surprise was beyond words. “Do you really mean that?”
“Every word of it,” was the old man’s reply. His little eyes twinkled. “Don’t you think much of the idea?”
Bob laughed.
“It was so sudden that I hadn’t given it a thought,” he answered. “But”—gazing far down the smooth slope—“it looks rather inviting. Will you go first?” The youth was not fully convinced that Dr. Rander was in earnest.
“If I go, one of you will have to stay with the pack animals,” the old man said. “I don’t think they had better try it,” he added with a laugh.
Bob and Joe looked puzzled.
“I don’t understand,” said the latter, hesitating. “Do you mean that some of us will slide down this slope and some stay with the mules—leave them here, I mean?”
“Oh, no,” smiled Dr. Rander. “One of us will have to take the mules down the trail. We could all go that way, but as it is very long, this offers a short cut that you fellows can take. That is, if you want to. When you get to the bottom you can wait until I get down the trail with the pack animals.”
“Where is the trail?” Bob secretly wondered if Dr. Rander had suddenly changed his mind about sharing the treasure with them and was using this means to evade them. He did not think the old man treacherous, but he wanted to be on the safe side.
“Over there.” Dr. Rander pointed to a narrow path that circled down the mountainside.
“Suppose,” Bob began, “you and Joe go down the slide while I take the mules down the trail. I don’t like the looks of that glassy slope.”
“All right. I’m no longer young, but I still like sport. Here I go.”
The next moment he was sliding rapidly down the polished incline.
When he was halfway down, Bob and Joe burst out in laughter. The sight of the old man doing such a thing as this with so much enjoyment aroused the youths’ sense of humor.
“If he likes it so much, maybe I will,” chuckled Joe, sitting down at the edge.
“Good luck,” called Bob, as his friend let go his hold and passed swiftly down.
It was an unusual sensation to Joe, as he shot down the curving slide. When younger he had often played on the slides in parks. But this was something entirely different. To shoot down a tall mountain at a rapid pace, on the straightaways and around curves, was indeed novel.
When over halfway down, the youth felt himself gradually lose momentum, and he knew that the slide was flattening out. Too steep a descent, especially near the bottom, would be dangerous.
At last he came to a stop beside Dr. Rander, who had been watching the descent.
“How did you like it?” the old man asked.
“All right. Got rather warm, though. Wonder if it thinned my trousers any? No, I guess not. Too smooth, I suppose.”
Fifteen minutes later Bob came in sight leading the line of mules. He laughed as he caught sight of them.
“Any worse for your experience?” the youth asked with a chuckle.
“Do we look it?” smiled Joe. “We enjoyed it.”
As the sun was almost directly overhead they decided to remain at this spot for the midday meal. All were extremely tired and hungry.
Bob prepared dinner, using water they had brought with them in canteens. As a dessert they feasted on the delicious wild cherries that they had picked that morning.
“Now let’s get going,” urged Joe, when the meal was over. “I’d like to see that treasure.”
Farther into the wilds they plunged, with not the faintest suggestion of a trail to guide them.
“No trace of any vegetation here,” observed Bob. “It’s a good thing we stopped where we did, or the mules probably wouldn’t have had anything to eat. There were a few stunted bushes and other plants back at the foot of the slide.”
An hour of climbing brought them to a place where a tall peak obstructed their view.
They trudged around and then suddenly found themselves at the bank of the roaring Apurimac River.
“On a little farther,” Dr. Rander said, urging the mules to ascend the difficult slope.
At last they came to a place where a high rock protruded far over the river. Here the old explorercalled a halt and pointed up the side of a mountain.
“In that little notch up there is the entrance to the treasure,” he said. “As I said before, there is a huge cave that occupies the entire mountain. There we will find the treasure, if there is any.”
The youths’ hearts beat rapidly. They could hardly believe that at last they were nearing the great secret.
“But,” hesitated Bob Holton, “how are we going to get across this roaring river?”
“That,” the old explorer returned, “will be the most difficult part of our entire journey. Come. Let me show you.”
They followed him to the edge of a high rock that protruded far out over the seething rapids.
“Look there,” he said, pointing to something.
Stretching from the rock across the river to another protruding crag was a heavy metal wire, which, strange to say, showed not the slightest trace of rust.
“That cable was put there by the Incas,” Dr. Rander said. “It is hundreds of years old, but still looks as if it had been built but yesterday. It is coated with some secret preservative, which prevents it from rusting through.”
“Interesting,” remarked Joe. “But what about it?”
The old man replied at once.
“We must cross the river by hanging from the cable with our hands,” he said quietly.
Joe’s heart sank. Secretly he felt that if he were to undertake the dangerous venture he would meet with tragedy.
“CAREFUL,now.”
Dr. Rander was slowly and dangerously hanging from the heavy wire with his hands, working his way steadily across the roaring rapids below. If he were to fall, it would probably seal his doom, even though the youths held one end of a stout rope that was tied securely around his waist.
“Think he’ll make it?” Bob looked on anxiously, half expecting to see the old man let go and plunge into the seething water below.
Slowly but surely he swung across, holding on with a grip of steel. It seemed remarkable that a person of his age could withstand the arduous tasks connected with exploration. But no doubt he was hardened to an eventful outdoor life of adventure.
“He’s over,” cried Joe happily. “Made it all right. Didn’t even threaten to let go. Now I wonder if we can do as well?”
The youths had yet to see.
Joe was next to swing across. He walked over to the cable and gazed doubtfully first at the boiling stream below, then at Dr. Rander on the opposite cliff.
“Go ahead,” said Bob. “Might as well get it over.”
“Yeah. But I wish it weren’t necessary to do this. I suppose, though, that I can do it if Dr. Rander can.”
Joe sat down on the edge of the cliff, took hold of the heavy wire, and slowly let himself down.
For a brief moment it seemed as if his arms would be torn from their sockets, for, although he was not heavy, the strain was very great.
“I’ve got to make it!” he told himself, gritting his teeth. He refused to think of what might happen if he were to plunge into the roaring rapids below.
“Don’t let go, whatever you do!” Bob, on the rock, was holding the rope tightly, ready to pull his friend to safety if the latter should be forced to release his grip.
Joe swung across with a certain determination that was luckily with him in every emergency. He did not look below for fear of becoming frightened.
At last, when he felt that he could stand no moreof this torture, the youth felt his foot touch rock, and he knew that he was safe.
“Hurrah!” cried Bob Holton, waving his arms in the air. “Now here I come.”
Bob would find the feat more difficult, since he was heavier than either of the two who had crossed. But usually when he set his mind on doing a thing he was able to do it.
But first he walked over to the mules, which had been tethered securely by Dr. Rander, and got out a stronger rope, which he tied around his waist and shoulders. A small weight he fixed at the other end, and then moved back to the edge of the rock.
“Here. Catch this,” he called, and threw the rope over to Joe on the other side of the river.
When everything was in readiness he slowly lowered himself until he could grasp the wire that stretched across the stream. Then, setting his nerves for the trying task, he let his feet drop.
For one awful minute Bob’s heart stood still. Then he got a grip on himself and swung easily across to the other side.
“That was fine!” praised Dr. Rander. “You never flinched. Now let’s hurry up the mountain to the treasure.”
“Do you suppose the mules will be safe over there?” queried Joe anxiously. “We couldn’t take any food with us across the river. If anything should happen to them——”
“There is no danger,” the old man assured him. “Probably no one has been in this section for years and years.”
Notwithstanding this, the young men were still worried. They realized that they would be in a grave predicament if anything should befall the provisions.
This anxiety gradually wore off, however, as they neared the treasure cave.
“Hard climb, but nothing will stop us now,” smiled Joe happily.
“You will be amazed when you look upon the wonders in the cave,” Dr. Rander told them. “It will exceed your wildest dream.”
“How did they all get there?” inquired Bob.
“I do not know. They were placed there by some wealthy Inca—perhaps a king—for safe keeping. It might have been that this was at the time of the Spanish invasion, and that the owner was later killed by the conquering troops. At any rate, the secret remained as such until I accidentally found it.”
“You sure were lucky,” remarked Joe. “Perhaps it wouldn’t have been discovered at all if you hadn’t located it.”
At a point near the ledge, the mountain grew so steep as to make climbing a very arduous task. A single misstep would have meant a horrible plunge into the roaring rapids below.
At last they came to the top of the ledge, before the notch cut in the mountainside.
“See that dark entrance?” asked Dr. Rander. “That is a tunnel that leads to the cavern. Come.”
The youths followed the old man into the opening, which was made light by the latter’s flashlight. The passage seemed to lead steadily upward, probably into the peak of the mountain.
“Do you suppose this tunnel was constructed?” asked Joe, after five minutes had passed.
“I believe so,” Dr. Rander returned. “When we get farther on, you will think so too.”
Fifteen minutes of walking brought them to the end of the tunnel. From all appearances there was nothing but natural rock before them.
“Watch,” said Dr. Rander, moving over to the end of the cave.
He reached up and pressed a mysterious button. Then he stepped back and waited.
Suddenly the youths gasped in awe, as they saw the huge stone wall slowly swing inward. As it made an opening, a beam of natural light flashed into the cave, making the use of a flashlight no longer necessary.
“Huh! That’s funny!” muttered Joe. “Must be an entrance to the outside somewhere.”
“If you can find it, it is more than I can do,” laughed Dr. Rander.
The opening grew larger, and the light brighter. When the ponderous stone wall had swung away to the utmost, Bob and Joe followed the old man through the entrance.
As they did so their eyes opened wide and their jaws dropped at the sight that lay before them. Ahead was a great stone room, fully fifty feet square, in which were scores of objects carved from stone. Statues of men, birds, llamas, pumas, and many other animals were all about. Ears of corn, plows, chairs, pottery—all these and many more objects were carved out of stone.
It was a wonderful collection, one that would delight the eye of any archæologist. Bob and Joe inspected the various objects with interest, knowing that Dr. Rust and his fellow scientists would give a great deal to know of the existence of this place of wonder.
“All this is very interesting,” remarked the old man. “But what we really came after was treasure—if there is any.”
“Yeah. Where is the place where you said it might be?” Bob was anxious to look for something still more valuable than the stone objects.
“I will show you.”
Dr. Rander stepped over to one corner of the large room, where was a huge statue of a man, perhaps an Inca king.
“Now look closely,” he said, when the youths had followed him.
The old man walked up to the statue and stood directly in front of it. Then he waited.
At that moment something happened that caused Bob and Joe to gasp in wonder. Slowly, surely, the statue sank into the floor until it disappeared from sight. Directly below the resulting opening was a ladder, which led down into another gigantic room.
“Well, of all things!” cried Joe in utter amazement. “That sure is a secret if there ever was one.”
“Let us go down.” Dr. Rander was making his way down the ladder, motioning for the youths to follow.
They did and soon found themselves in a huge cavern cut out of solid rock. Here were more stone objects similar to the ones in the room above them.
“This way,” pointed out the old man, walking over to one side of the cave.
“Wonder where the light comes from?” pondered Bob. “It’s from the outside, all right, but how does it get in?”
Dr. Rander bent over and pressed something in a crack in the floor, straightening up a moment later.
Again the youths were filled with amazement. A huge stone block swung away on unseen hinges, leaving an opening perhaps four feet in width.
“Now we must use flashlights,” Dr. Rander said, stepping inside. “There is no opening to the outside, apparently.”
The beams of the electric torches revealed the fact that they were in another cave.
“Over here,” explained the old man, “is a sort of bin cut out of the rock. It is covered with a stone that I cannot lift. But I feel sure that all three of us can.”
“Let’s have a look at it,” said Bob.
Together they heaved on the stone block with all their strength. Before long they saw that their efforts were not in vain. The stone was slowly slipping from the top of the bin. At length it fell to the floor with a dull thud.
The explorers turned the beams of the flashlights into the opening, looking about eagerly.
“Here’s something,” announced Joe, bringing out a small iron box.
“Open it,” directed Dr. Rander.
Joe did—and then cried out in wonder as he saw its contents.
“GOLD!”cried Joe happily. “Gold beads, as sure as I’m alive!”
“And scores of them, too,” observed Bob. “Bet they’re worth hundreds and hundreds of dollars.”
They examined the little objects with interest, joyful that at last their efforts had been rewarded. The beads still shone brightly, although they had been in the cavern for hundreds of years. That they were really gold, no one doubted in the slightest.
“Who put them here?” asked Bob Holton, when they were ready to leave for the outside, the jewel box in their possession.
“The Incas,” returned Dr. Rander. “Perhaps it was an Inca king. At any rate it was someone who was wealthy.”
They looked about for any other treasure that might be in the room, but found none. At last they left the cave, closing the stone door behind them.
Led by Dr. Rander, they climbed the ladder,and then passed through the great room that was filled with the stone statues.
“We must hurry before it gets dark,” said Dr. Rander, closing the secret stone wall by pressing the hidden button. “It will not do to cross that river at night.”
“Bad enough in the daytime,” added Joe, as they made their way through the dark tunnel.
When at last they reached the outside they saw that they had but a few minutes before the sun would sink from sight.
Down the steep slope they climbed until at last they reached the cliff which protruded over the roaring river.
“How are we going to get the jewel box across?” asked Joe. “It isn’t large, but it’s too big to put in our pockets.”
“Use a rope, I suppose,” was the answer from Bob. “We’ll tie it tightly across somebody’s back.”
This suggestion was followed, and before long the three were on the other side of the rapids. They were relieved to find that the mules were resting peacefully.
“I don’t like the idea of crossing that river any more,” said Bob with a frown. “But I would like to go over to the secret cavern again tomorrow.”
“What for?” demanded Joe.
“I have two good reasons,” his friend answered.“First, I would like to take some movies of the place. And the other one is that I’d like to make a detailed map to give to Dr. Rust and the other archæologists. They’ll appreciate it, all right. Be tickled to death to know that we found all those Inca remains.”
The next morning they did as Bob wished and once more swung themselves across the boiling rapids, coming to the opposite side safely.
Motion pictures of the secret cavern and its contents were taken, and then a reliable map was made of the region, including the exact location of the mysterious buttons that moved the large stone doors.
Although Bob was assisted by his friends, he did not have everything completed until noon.
With one last look at the mountain of secrets, the three turned and retraced their footsteps to the river.
“Last time across,” said Joe with a sigh of relief. From the start he had feared the dangerous swing from the cable.
No harm befell them, however, and they reached the other side ready to start the journey to Pasaje, where Karl Sutman would be waiting with his airplane.
“Good old Karl,” said Bob affectionately. “It will be fine to see him again. And Dad and the others. I hope they’re all right.”
“With you on that,” came from Joe quickly.
“It will take us many days to get to Pasaje,” Dr. Rander put in. He intended to go with the youths to that town, where he wished to remain for several days.
“Wonder if we’ll see anything more of interest?” Joe was anxious to observe all that was worthwhile.
“There are other secrets I will show you,” explained Dr. Rander. “But as far as I know there is no more treasure.”
They decided to rest the remainder of that day, for all were tired from the strain. On a little shelf beside the roaring Apurimac they made camp.
“Now lead us to more secrets,” said Bob the next morning, when they were ready to resume the journey.
“I will,” returned the old man.
He kept his promise. Late that afternoon they had been following a narrow trail that curved with the river when Dr. Rander stopped and pointed up to a tall peak.
“Beyond that is a little hidden valley,” he told the youths. “In it is a tall tower that was built by the Incas. As far as I know, I am the only person who has ever found it.”
“Sounds interesting,” said Joe. “Can we go there?”
“Yes. Follow me.”
He tied the mules securely and then began the dangerous ascent of the high peak, Bob and Joe at his heels.
After a half-hour of struggling they reached the summit, which was covered with a thin coating of snow.
“Now, look down,” the old man said.
Far, far below, on the other side of the mountain, was a narrow valley that was green with tropical vegetation. It appeared much lower than might be expected.
“Look away over to your right,” directed Dr. Rander. “See that tall tower?”
“Why—why, yes!” Bob was struck with wonder. “Let’s go down and see it. Have you ever been there?” he asked the old man.
“Not close,” was the reply. “I have only looked at it from a distance. Lack of time prevented me from going over there.”
“We haven’t a great deal of time,” said Joe. “But I wouldn’t miss taking that in for hardly anything.”
He led the way down the steep slope, which required not a little caution. A single misstep would have meant a terrible fall to the bottom of the cañon.
An hour of careful climbing and their feet touched the green grass below. The tower, theyobserved, was several hundred yards in the distance.
“Probably we will find other ruins near,” remarked Joe Lewis, as they walked toward the corner of the narrow valley.
“Where there is one there is likely to be two,” smiled Dr. Rander. “And maybe you’re right.”
When they came nearer they saw that the tower was at least a hundred feet high. It was built of small blocks of stone, carefully fitted together. Near the base was a heavy growth of vines and creepers, which wound around the tower up to a height of twenty feet.
“Here’s a door,” called Bob, who had gone around the other side. “Let’s go in and see what we can find.”
With the aid of small flashlights they entered the structure and looked about.
Everywhere were cobwebs and other evidences of age, showing that it had not been occupied for hundreds of years. In one corner was a narrow winding stairway, which evidently led to the top.
“Shall we go up?” asked Joe.
“Sure. Why not?” Bob was already halfway up the first flight.
The others followed him, winding slowly up the narrow stairs. They wondered a little if itmight be safe to venture up into this time-worn structure.
After what seemed like hours, they left the last flight of stairs and turned to go out on the top floor.
As they did so, they saw something that was horrible and disgusting.
LYINGabout on the stone floor were at least ten human skeletons, which were white with age. They were in no fixed positions, but were scattered aimlessly over the dusty floor.
Bob was the first to break the silence.
“Wonder how they got here?” he asked.
“Perhaps they are the remains of soldiers who guarded this tower,” was the opinion of Dr. Rander. “Here,” he went on, “look at this. It’s a dagger—made of stone.”
“You might be right,” commented Joe. “But then, it’s possible that the dagger belonged to someone who came up and murdered those who were here.”
The explorers examined the skeletons for several minutes before going to the edge and looking down on the surrounding valley.
“Can see quite a distance,” observed Bob, peering out at a distant mountain.
“Yes,” agreed Joe. “There——”
At that moment he was interrupted by a cracking noise, which seemed to come from the tower.
“What’s that?” cried Dr. Rander excitedly.
But when it was repeated, there was no doubt in their minds as to the origin of the strange noise.
“It’s the tower!” exclaimed Bob fearfully. “I hope I’m wrong, but I’m afraid it’s going to fall. Hurry! Let’s get down to the ground.”
The three lost no time in scrambling down the stairs. They reached the bottom in safety, and then dashed outside, Dr. Rander displaying remarkable agility for his age.
Then something happened that filled them with terror. With one last creak, the old tower leaned slowly to the south, poised for a brief moment, and went crumbling to the ground. There was a report like that of a cannon, followed by a heavy cloud of dust and small particles of rock.
The explorers’ hearts were beating like trip hammers; their faces were red with excitement.
“Thank God that we escaped in time!” breathed Dr. Rander. “A few seconds more and we would have been caught beneath tons of rock!”
“And what a death!” muttered Joe with a shudder. “I don’t want to even think of it.”
They sat down on the ground to relieve themselves of the terrible strain. Especially did the oldman show signs of exertion. At first the youths half expected to see him fall with heart failure, for he was terribly exhausted.
The rest, however, did him good, and before long he was apparently no worse for the horrible experience.
“Funny that tower should collapse just at this time, isn’t it?” said Bob. “I suppose, though, that it was ready to go at any time, and our weight proved too much for it.”
“That probably explains what happened,” came from the old man. “If no one had found it, perhaps it would have remained intact for many years yet.”
They put in no more time here, but turned and went back to the peak.
Very difficult it was to scale the steep slope, but at last they reached the top and descended to the other side.
“The mules are all right,” observed Bob. “Suppose we get going without delay. I’d like to get to Pasaje as soon as possible. I’m getting anxious to see Dad and the others of the expedition.”
“It will still take time,” Dr. Rander told him. “There are many miles of difficult travel before us.”
And difficult it was. Although the adventurers had previously found it hard to make progressthrough the rugged mountains, they now experienced even more hindrances.
Unfortunately, Dr. Rander was not overly familiar with this section and often made mistakes in pointing out the best course of travel.
It was not uncommon for the adventurers to come upon heavy forests at elevations of fifteen thousand feet. This surprised Bob and Joe, who did not expect to see trees growing at such high altitudes.
“There really is no such thing as the ‘tree line’ in the Andes,” explained the old explorer. “In fact, it is possible to find forests at unusually high altitudes.”
As they trudged on they came to more wild-cherry plants, the fruit of which they ate hungrily. It was refreshing to have fresh fruit after eating nothing but dried goods.
As much as possible they followed the banks of the Apurimac River, for Pasaje, their destination, is situated just above the point where the stream branches.
As they went farther, the mountains became more lofty, and snow on the summits was more common. They never climbed high enough, however, to come in contact with it.
Suddenly, upon hearing an unusual noise, Joe glanced around, and then gasped in apprehension.
“One of the mules is stuck in mud!” he cried. “Quick! We must do something at once!”
Without delay the old man turned about, walked back to one of the pack animals, and secured a long heavy rope. Then he moved on to the rear of the line, where one of the mules was struggling to free itself from the black bog.
“Bob, you had better come to the rescue,” he said, after a moment of pondering. “You’re pretty good at lassoing, as you showed us several days ago on that narrow ledge. Won’t you try it and see what you can do?”
“Where will I throw the rope, over the mule’s head?”
“Yes. Tighten it around the animal’s neck.”
“But—won’t it choke?”
“Not for a few minutes. There is no other way to pull the mule out. If we go too close we’ll get caught ourselves.”
“All right, then. Here goes.”
Bob took the rope, made a loop, and stepped as near as he thought possible with safety.
“If I miss my aim, I can’t help it,” the youth said, as he threw the lasso.
Joe cried out happily as he saw that the loop went directly over the mule’s head. Dr. Rander’s face also lightened.
All three pulled on the rope with all their strength, but their efforts appeared to be in vain.The treacherous bog had engulfed its helpless victim too tightly.
“We’ve got to get that animal out!” cried Joe, redoubling his efforts. “There’s a lot of valuable supplies on its back.”
But how? They were doing all they knew of. If that were not sufficient, the mule would have to go down.
“We’re losing steadily,” observed Bob grimly. “But I guess we can’t help it.”
Despite their furious efforts to draw the beast to safety, it was sinking rapidly. Already its body was nearly under. In but a brief time its head, too, would be engulfed.
But the adventurers kept up doggedly, determined to win the battle even though defeat was staring them in the face.
With one last effort, they gave the rope a new stronger pull. But it was not enough. The weight of the mule and its burden was too much, and the animal’s head slid horribly into the oozing mud, to disappear forever.
Bob slumped down on the grass.
“We lost,” he murmured gravely. “Now we’re one pack animal short.”
“And there were quite a few valuable objects in the pack, too,” added Joe, “not to say anything about losing the animal.”
“Have to get along some way,” Dr. Randersaid. “There is no use in thinking anything more about it.”
“Wonder what the mule thought about when he went under?” mused Joe. “It must have been terrible.”
They resolved to follow the old man’s suggestion and forget the loss as best they could. After all, it was lucky that one of them had not been the victim.
Again they took up the journey, this time keeping a closer lookout for other bogs. But Dr. Rander did not know this region any too well, and could not guide them as surely as he would have liked to.
In the fascinating mountains the time passed rapidly. It was two days after they had lost the mule when Dr. Rander pointed to something in the distant sky.
“That’s a condor,” he said, his eyes trying to make out the flying form more clearly.
“It is at that,” affirmed Bob, looking through his binoculars. “And what’s more, it’s white. Acondor real, as sure as I’m standing here!”
“Let’s see,” said Joe, and took the glasses his friend handed him.
A few moments of observing and he nodded, giving the binoculars to the old man.
“You’re right,” Joe said to his chum. “And oh! Wouldn’t our dads and Mr. Wallace like to behere now! A white condor! One of the creatures they wanted most.”
“Maybe we can get it for them,” muttered Bob, grasping a shotgun. “Do you suppose there’s a chance?”
“Not unless it flies nearer,” returned Dr. Rander. “Even then the bird would probably fall to the bottom of the cañon, and that would mean a dangerous descent.”
“I’m going to see, anyway,” Bob persisted, following the soaring form through his powerful binoculars.
“Look what I’ve found,” called Joe, who had climbed down to a narrow ledge several yards below the others.
“Why—it’s a nest,” exclaimed Bob, upon descending to the shelf. “And look at those eggs. Sure are whoppers. Say,” he cried suddenly, “I bet I know everything now. This belongs to that white condor. Look. There’s a white feather. See it?”
“You’re probably right,” said Dr. Rander, moving down to the ledge. “Let us look about more. We may find something else of interest.”
But all searching was stopped a second later when Joe happened to glance up.
“The condor!” he cried fearfully. “It’s coming at us!”
THEREwas not a moment to lose. With the huge white condor swooping down upon them, the explorers knew that they must act quickly. Unfortunately their rifles had been left on the trail above. Before they could secure the weapons the huge bird would be upon them and would probably use its terrible claws and beak to great advantage.
“My knife is all we have to defend ourselves with,” said Joe, watching the large form advance toward them. “But I’m going to use it.”
The condor came on swiftly. It circled around a few times near its nest and then rushed madly at the little group of adventurers.
Now it was barely ten feet away and coming with deadly aim. In but a brief moment it would be in a position where it could work deadly havoc with its sharp claws.
Joe had his long hunting knife in readiness now,waiting for an opportune moment. Then it came.
The huge white bird was soaring directly above its human enemies. As it dropped lower, Joe lunged forward and plunged the sharp knife through one of the long, thin legs.
Uttering a curious sound, the condor darted away, circled around for a brief period, and then flew at the explorers with a new determination.
One of the horrible claws shot out and caught Joe’s arm, the impact knocking the knife from the youth’s hand. It went hurtling to the bottom of the abyss, far below.
Joe was weaponless, helpless!
New horror crept over him when he suddenly felt himself leaving the ground. Not fifteen feet away was the edge of the cliff! Vainly he tried to escape from the clutch of that formidable claw.
Meanwhile, Bob and the old man were not inactive. They knew that it would only be a short time before their friend would be carried over the brink of the cliff. And that must be prevented at any cost.
Looking wildly about, Bob caught sight of a rock about half as large as a brick. Almost frantic, he picked it up, and with desperate strength he sent it crashing into the condor’s body.
The force was terrific, and for a moment it seemed as if the condor were going to drop. Butit righted itself and carried the helpless Joe still farther toward the rocky edge.
“I’m going to try something,” blurted out Bob, his face red with an awful fear. “You run up to the mules and get a rifle—quick!” he said to Dr. Rander.
As a last resort, Bob hurled his hundred and eighty pounds at Joe’s feet, and caught hold with a grip of steel. He wondered if the huge bird could lift both himself and his friend. If it could....
At that moment Dr. Rander scrambled down the rocky slope with a rifle, which he aimed unflinchingly at the condor’s body. The next moment the gun barked.
With a terrific fluttering of its heavy wings, the bird sank slowly to the ground. It touched the hard soil, and then with a convulsive twitch it lay still.
For almost a minute there was silence among the little party of adventurers. They were panting furiously, and their wide eyes had not yet lost their look of terror. Perspiration was streaming from them, making their faces shine gruesomely. It had been one of the narrowest escapes they had had so far.
Finally Joe wiped his face and looked at Bob with intense gratitude. Then his eyes fell on Dr.Rander, whose rifle was still warm from the timely shot.
“I don’t know how to thank you,” he said warmly. “If you hadn’t been so plucky, I would probably be lying in a broken mass at the bottom of the gorge right now. It was simply wonderful!”
“Forget it!” Bob disclaimed any praise offered him. “The only thing now that matters is that you’re alive.”
“Thank Bob for that,” the old man said. “If he had not thrown himself at your feet you would surely have gone over the cliff.”
“But it was your shot that finished the job,” protested Bob Holton. “Even with the weight of both of us the condor was slowly dragging us toward the brink.”
“I’m afraid my bullet would have been too late if you hadn’t done what you did,” persisted the old man.
“All right. Have it your own way.” With a laugh Bob dropped the matter and stooped over to examine the huge white bird.
It must have had a wing spread of over ten feet. Later measurements showed that this was accurate. But what impressed the youths most was its pure white feathers, which looked as clean as if they had been recently washed. The terrible claws and long sharp beak next caught the youths’eyes, and their respect for the power of this monstrous bird was increased.
“Quite a specimen,” observed Joe. “And speaking of specimens,” he went on, “why can’t we skin it and take it with us? Our dads and Mr. Wallace would sure be tickled. The white condor! Boy! I can just see them giving cries of delight.”
“Nothing to prevent us,” returned the other youth. “We may find it hard to place in our mule train, but we’ll manage some way.”
Bob secured a long knife, and with a skill that he learned while on other hunting trips he cut the bird’s skin open down the breast. A few minutes more and the task was completed.
Without the weight of the body, the skin was light, and they had no difficulty in tying it over the back of one of the mules, which appeared not to notice the extra load.
With one last look at the spot where Joe had almost met his death, they turned and drove the pack animals ahead on the remainder of the journey to Pasaje.
But now they were more anxious than ever to reach their destination and fly with Karl Sutman to the place where their fathers were hunting. With every minute they longed still more to reach the town they were approaching.
“I hope nothing further comes up to stay us,”remarked Bob, as they descended a steep slope. “Somehow I’ve had enough excitement for a while.”
“So have I,” said Joe. “But of course there’s no way of telling what we may meet in these mountains.”
The next day they found themselves in a wide valley, which was covered with a heavy growth of dense vegetation. Tree ferns were quite prominent, growing in large clusters that dotted the valley. Bright flowers were also numerous, some of them unusual in shape and form.
And with this heavy vegetation came several varieties of wild animals, among them being foxes, lizards, guinea pigs, and a host of birds. The youths could easily have shot some, but they did not wish to lose time in doing so.
“I believe we are getting close to Pasaje now,” announced the old man, as he led the way around the winding Apurimac River.
Notwithstanding this, they traveled all that day without coming to the town. Camp was made at a clearing near the stream, supper was prepared, and then all retired, knowing that the following day would witness their coming to their destination.
Early the next morning the young men saw something that thrilled them with delight. Theyhad been breaking camp and were almost ready to resume the tramp when suddenly their keen ears caught the sound of a motor. Looking up, they plainly made out an airplane in the sky above them.
“That’s Karl!” cried Joe joyously. “I wouldn’t be afraid to bet anything that it is.”
“I sure hope you’re right,” came from Bob. “Gee! Won’t it be swell to see him again?”
“Of course there’s a chance that he won’t see us,” said the other boy. “But I believe he will. He’ll be looking around for us closely. Maybe that’s why he’s here now.”
Bob started, as an ominous thought struck him.
“Do you suppose anything’s happened—to our dads, I mean?” he asked in a tense voice.
Joe’s face darkened.
“I—I hadn’t thought of that,” he replied solemnly.
They watched the airplane closely, expecting at every moment to see it head downward.
Then it came.
“Hurrah!” Bob was overjoyed. “Karl sees us, all right. And it’s Karl, too,” he observed, as the monoplane came closer.
As the machine flew closer it circled around the little group below, rapidly flying lower. When within a hundred feet of them, its cabin window opened, and Karl’s face was thrust out.
“Hello, up there!” shouted Bob, and received an answering greeting. But the noise of the ’plane’s engine made it impossible for the adventurers to understand the aviator’s words.
While the three were still gazing up at the huge monoplane they saw something that caused them to look all the closer. They made out Karl’s arm reaching out of the cockpit. Then they saw something white drop toward the ground.
“It’s a small parachute,” observed Joe, his heart beating rapidly. “Wonder what’s tied to it?”
As there was no wind, the object fell in a straight line, the parachute opened and began to float slowly above the onlookers. Before long it came to the ground within fifteen feet of them. Karl had certainly aimed accurately.
“Hurry!” cried Joe. “Let’s see what it is. Maybe something’s happened to our dads or the others.”
He picked up the parachute, at the end of which was attached a small box. Opening it, the youth found a folded paper.
“Quick!” murmured Bob. “Let’s see what he has to say.”
RATHERnervously Joe unfolded the paper, hastily read it, and then gave a sigh of relief.
“Nothing wrong,” he told his friends. “Take a look.”
“H’m,” observed Bob. “He only says he’s going to land in a level field about a mile from here, and that he’d better take us up with him from there, instead of waiting till we get to Pasaje. No other place near to land on. Closes by saying everything is all right.”
“So he wants us to go up with him now,” mused Joe. “Doesn’t want to wait till we get to Pasaje. I hate to do that. I don’t like to leave Dr. Rander till we get to the town. It doesn’t seem right to come with him all this distance and then go off and leave him here in the mountains.”
“Don’t worry about me,” said the old explorer quickly. “I have been through these mountainsalone many times. I can manage the mules all right. And the town can’t be far away.”
“We’d go with you anyway,” Bob told him, “only Karl says there isn’t another landing place near.”
Without loss of time the three continued toward the level spot on which the aviator had landed, at length coming in sight of the monoplane.
Karl rushed out to meet them, his face bright at finding that all were alive and well.
“You old rascal!” cried Joe, shaking the young man’s hand warmly.
“How’d you know we were here?” asked Bob, who was also very glad to see the aviator.
“I saw you,” Karl Sutman explained. “I thought I’d take a short flight over this section to see if I could locate you.”
“You did, all right.” Joe was delighted. “Found us away out here in the wilds.” He hesitated a moment and glanced at Dr. Rander. But the latter had already been introduced to Karl Sutman, and needed no introduction by the youths.
There was one question in the aviator’s mind that he could wait no longer to ask.
“The treasure you were searching for—did you find any?” he inquired. “And the Inca secrets, too. How about them?”
Bob smiled happily.
“We did,” he answered. “Found both the treasure and the secrets.”
When shown the little box of gold trinkets, Karl gasped in astonishment.
“Is that all you found?” he demanded. “I thought there might have been some gold statues, or the like.”
“If there were we couldn’t locate them,” Joe said. “We considered ourselves lucky in finding what we did. They are worth many hundreds of dollars, maybe thousands.”
“Dad and Mr. Lewis and the others—are they all right?” Bob was anxious to learn if any misfortune had befallen his father and friends.
“They’re still hunting for specimens,” returned the aviator. “Mr. Wallace fell down a mountain and hurt himself slightly, but he’s about all right now. And you should see the large collection of birds and animals they have.”
“We have something that may interest them,” declared Joe, and showed Karl the huge condor, at the same time telling about his narrow escape from death.
“Wow!” Karl exclaimed when the youth had finished. “And Bob and Doc Rander came to your rescue, did they? Good for them.”
It was later decided that Bob and Joe accompany Karl at once in the monoplane to the ComberciatoRiver, where the chums’ fathers were collecting specimens. The old man explained that he did not mind going on alone to Pasaje, where he had business.
“But before you leave,” Dr. Rander began, “I want to divide the treasure with you fellows,” addressing Bob and Joe.
“Don’t give us half,” Joe said pleadingly. “After all, it was your efforts that located the secret mountain cavern.”
The old man held up a hand for silence.
“You forget that I owe my life to you,” he reminded them. “If it had not been for your coming to my rescue, I would not be here to enjoy the treasure.”
“But——” began Joe.
“Say no more,” Dr. Rander silenced him. “Half of the gold is yours.”
He spent the next half-hour in dividing the treasure, giving the boys a good share. They thanked him warmly, then turned to Karl Sutman.
“Can we get started before long?” asked Joe. “I’m anxious to see everybody.”
“Sure.” The aviator was willing. “Let’s get your stuff loaded in the ’plane.”
They worked steadily until noon, at which time everything that belonged to the youths was packed in the supply compartment of the monoplane.
After the meal they bade Dr. Rander an affectionate farewell and stepped into the cabin. Karl started the engine, and then, with a roar and a rush, they started rolling over the field.
The old man waved as they left the ground and headed toward the north. The last the air travelers saw of him he was getting the pack animals ready to finish the journey to Pasaje.
“I suppose we’ve seen the last of him,” remarked Bob, as they left the ground. “We may hear from him later, though. He has our addresses.”
“Rather an odd character, isn’t he?” said Joe. “Seems strange that he’d want to remain in these mountains all his life.”
During the next few hours Karl sent the airplane ahead over mountains that were more rugged than any the youths had ever seen before. He was steering the machine near Mount Panta and the locality in which were Dr. Rust and the other archæologists when suddenly he found himself almost unconsciously entering a heavy cloud.
A second later, when he realized what he had done, the aviator saw that it was too late. Already the ’plane was in the midst of a heavy opaque atmosphere of white.
“I was a nut for getting in a place like this,” Karl said through the telephone. “And there’s noway of getting out now only to go on through it.”
Karl well knew that they were in grave danger of crashing into the side of some lofty peak. They were in a region of tall mountains, and some high summit might easily loom up before them.
For the next few minutes the youths’ hearts were in their mouths. They knew that Karl was an excellent pilot, but they also knew that he could do nothing if sudden tragedy might come upon them.
“What’s that?” cried Bob quickly. He had seen something that looked like a huge black mass directly before them.
Joe sat on the edge of his seat, expecting every moment to feel a terrible crash and then.... For the first time he wondered what death was like.
Cries of relief came from the youths as they saw that instead of crashing into the black mass, they were passing through it.
“As if a million pounds were lifted off my back,” gasped Joe. “I thought we were goners sure.”
“Would be if that were a mountain,” Bob said. “As it is, we’re no worse off than before. It’s a lot darker, though.”
Karl sought to pass out of the cloud by gaining altitude, but he soon saw that this was useless. Still, he thought it best to fly higher. There was a limitto the height he could safely reach, however, for neither himself nor the youths were using oxygen, and the high rare air was not sufficient to supply enough necessary to the human body.
“I’ll have to trust to luck, I guess,” he said through the telephone. “We may make it all right.”
“Karl didn’t say that any too hopefully,” remarked Joe. “Do you suppose he really fears disaster?”
“It seems like it.” Bob was terribly worried. He did not have much hope of getting out unharmed.