There was a dull, muffled report, a sort of rumbling that seemed to extend away down under the earth and then echo back again until the ground near the mouth of the tunnel, where the party was standing, appeared to rock and heave. There followed a cloud of yellow, heavy smoke which made one choke and gasp, and Tom, seeing it, cried:
"Down! Down, everybody! There's a back draft, and if you breathe any of that powder vapor you'll have a fearful headache! Get down, until the smoke rises!"
The tunnel contractors and their men understood the danger, for they had handled explosives before. It is a well-known fact that the fumes of dynamite and other giant powders will often produce severe headaches, and even illness. Tom's explosive contained a certain percentage of dynamite, and he knew its ill effects. Stretched prone, or crouching on the ground, there was little danger, as the fumes, being lighter than air, rose. The yellow haze soon drifted away, and it was safe to rise.
"Well, I wonder how much rock your explosive tore loose for us, Tom," observed Job Titus, as he looked at the thin, yellowish cloud of smoke that was still lazily drifting from the tunnel.
"Can't tell until we go in and take a look," replied the young inventor. "It won't be safe to go in for a while yet, though. That smoke will hang in there a long time. I didn't think there'd be a back draft."
"There is, for we've often had the same trouble with our shots," Walter Titus said. "I can't account for it unless there is some opening in the shaft, connecting with the outer air, which admits a wind that drives the smoke out of the mouth, instead of forward into the blast hole. It's a queer thing and we haven't been able to get at the bottom of it."
"That's right," agreed his brother. "We've looked for some opening, or natural shaft, but haven't been able to find it. Sometimes we shoot off a charge and everything goes well, the smoke disappears in a few minutes. Again it will all blow out this way and we lose half a day waiting for the air to clear. There's a hidden shaft, or natural chimney, I'm sure, but we can't find it."
"Thot blast didn't make much racket," commented Tim Sullivan. "I doubt thot much rock come down. An' thot's not sayin' anythin' ag'in yer powder, lad," he went on to Tom.
"Oh, that's all right," Tom Swift replied, with a laugh. "My explosive doesn't work by sound. It has lots of power, but it doesn't produce much concussion."
"We've often made more noise with our blasts," confirmed Job Titus, "but I can't say much for our results."
They were all anxious, Tom included, to hurry into the tunnel to see how much rock had been loosened by the blast, but it was not safe to venture in until the fumes had been allowed to disperse. In about an hour, however, Tim Sullivan, venturing part way in, sniffed the air and called:
"It's all right, byes! Air's clear. Now come on!"
They all hurried eagerly into the shaft, Mr. Damon stumbling along at Tom's side, as anxious as the lad himself. Before they reached the face of the cliff against which the bore had been driven, and which was as a solid wall of rock to further progress, they began to tread on fragments of stone.
"Well, it blew some as far back as here," said Walter Titus. "That's a good sign."
"I hope so," Tom remarked.
There were still some fumes noticeable in the tunnel, and Mr. Damon complained of a slight feeling of illness, while Koku, who kept at Tom's side, murmured that it made his eyes smart. But the sensations soon passed.
They came to a stop as the face of the cliff loomed into view in the glare of a searchlight which Job Titus switched on. Then a murmur of wonder came from every one, save from Tom Swift. He, modestly, kept silent.
"Bless my breakfast orange!" cried Mr. Damon. "What a big hole!"
There was a great gash blown in the hard rock which had acted as a bar to the further progress of the tunnel. A great heap of rock, broken into small fragments, was on the floor of the shaft, and there was a big hole filled with debris which would have to be removed before the extent of the blast could be seen.
"That's doing the work!" cried Job Titus.
"It beats any two blasts we ever set off," declared his brother.
"Much fine!" muttered the Peruvian foreman, Serato.
"It's a lalapaloosa, lad! Thot's what it is!" enthusiastically exclaimed Tim Sullivan. "Now the black beggars will have some rock to shovel! Come on there, Serato, git yer lazy imps t' work cartin' this stuff away. We've got a man on th' job now in this new powder of Tom Swift's. Git busy!"
"Um!" grunted the Indian, and he called to his men who were soon busy with picks and shovels, loading the loosened rock and earth into the mule-hauled dump cars which took it to the mouth of the tunnel, whence it was shunted off on another small railroad to fill in a big gulch to save bridging it.
Tom's first blast was very successful, and enough rock was loosed to keep the laborers busy for a week. The contractors were more than satisfied.
"At this rate we'll finish ahead of time, and earn a premium," said Job to his brother.
"That's right. You didn't make any mistake in appealing to Tom Swift. But I wonder if Blakeson & Grinder have given up trying to get the job away from us?"
"I don't know. I'd never trust them. We must watch out for Waddington. That bomb on the vessel had a funny look, even if it was not meant to kill Tom or me. I won't relax any."
"No, I guess it wouldn't be safe."
But a week went by without any manifestation having been made by the rival tunnel contractors. During that week more of Tom's explosive arrived, and he busied himself getting ready another blast which could be set off as soon as the debris from the first should have been cleared away.
Meanwhile, Professor Bumper, with his Indian guides and helpers, had made several trips into the mountain regions about Rimac, but each time that he returned to the tunnel camp to renew his supplies, he had only a story of failure to recite.
"But I am positive that somewhere in this vicinity is the lost Peruvian city of Pelone," he said. "Every indication points to this as the region, and the more I study the plates of gold, and read their message, the more I am convinced that this is the place spoken of.
"But we have been over many mountains, and in more valleys, without finding a trace of the ancient civilization I feel sure once flourished here. There are no relics of a lost race—not so much as an arrow or spear head. But, somehow or other, I feel that I shall find the lost city. And when I do I shall be famous!"
"Mr. Damon and I will help you all we can," Tom said. "As soon as I get ready the next blast I'll have a little time to myself, and we will go with you on a trip or two."
"I shall be very glad to have you," the bald-headed scientist remarked.
Tom's second blast was even more successful than the first, and enough of the hard rock was loosed and pulverized to give the Indian laborers ten days' work in removing it from the tunnel.
Then, as the services of the young inventor would not be needed for a week or more, he decided to go on a little trip with Professor Bumper.
"I'll come too," said Mr. Damon. "One of the sub-contractors whose men are gathering the cinchona bark for our firm has his headquarters in the region where you are going, and I can go over there and see why he isn't up to the mark."
Accordingly, preparations having been made to spend a week in camp in the forests of the Andes, Tom and his party set off one morning. Professor Bumper's Indian helpers would do the hard work, and, of course, Koku, who went wherever Tom went, would be on hand in case some feat of strength were needed.
It was a blind search, this hunt for a lost city, and as much luck might be expected going in one direction as in another; so the party had no fixed point toward which to travel. Only Mr. Damon stipulated that he wanted to reach a certain village, and they planned to include that on their route.
Tom Swift took his electric rifle with him, and with it he was able to bring down a couple of deer which formed a welcome addition to the camp fare.
The rifle was a source of great wonder to the Peruvians. They were familiar with ordinary firearms, and some of them possessed old-fashioned guns. But Tom's electric weapon, which made not a sound, but killed with the swiftness of light, was awesome to them. The interpreter accompanying Professor Bumper confided privately to Tom that the other Indians regarded the young inventor as a devil who could, if he wished, slay by the mere winking of an eye.
Mr. Damon located the quinine-gathering force he was anxious to see, and, through the interpreter, told the chief that more bark must be brought in to keep up to the terms of the contract.
But something seemed to be the matter. The Indian chief was indifferent to the interpreted demands of Mr. Damon, and that gentleman, though he blessed any number of animate and inanimate objects, seemed to make no impression.
"No got men to gather bark, him say," translated the interpreter.
"Hasn't got any men!" exclaimed Mr. Damon. "Why, look at all the lazy beggars around the village."
This was true enough, for there were any number of able-bodied Indians lolling in the shade.
"Him say him no got," repeated the translator, doggedly.
At that moment screams arose back of one the grass huts, and a child ran out into the open, followed by a savage dog which was snapping at the little one's bare legs.
"Bless my rat trap!" gasped Mr. Damon. "A mad dog!"
Shouts and cries arose from among the Indians. Women screamed, and those who had children gathered them up in their arms to run to shelter. The men threw all sorts of missiles at the infuriated animal, but seemed afraid to approach it to knock it over with a club, or to go to the relief of the frightened child which was now only a few feet ahead of the animal, running in a circle.
"Me git him!" cried Koku, jumping forward.
"No, Wait!" exclaimed Tom Swift. "You can kill the dog all right, Koku," he said, "but a scratch from his tooth might be fatal. I'll fix him!"
Snatching his electric rifle from the Indian bearer who carried it, Tom took quick aim. There was no flash, no report and no puff of smoke, but the dog suddenly crumpled up in a heap, and, with a dying yelp, rolled to one side. The child was saved.
The little one, aware that something had happened, turned and saw the stretched out form of its enemy. Then, sobbing and crying, it ran toward its mother who had just heard the news.
While the mothers gathered about the child, and while the older boys and girls made a ring at a respectful distance from the dog, there was activity noticed among the men of the village. They began hurrying out along the forest paths.
"Where are they going?" asked Tom. "Is there some trouble? Was that a sacred dog, and did I get in bad by killing it?"
The interpreter and the native chief conversed rapidly for a moment and then the former, turning to Tom, said:
"Men go git cinchona bark now. Plenty get for him," and he pointed to Mr. Damon. "They no like stay in village. T'ink yo' got lightning in yo' pocket," and he pointed to the electric rifle.
"Oh, I see!" laughed Tom. "They think I'm a sort of wizard. Well, so I am. Tell them if they don't get lots of quinine bark I'll have to stay here until all the mad dogs are shot."
The interpreter translated, and when the chief had ceased replying, Tom and the others were told:
"Plenty bark git. Plenty much. Yo' go away with yo' lightning. All right now."
"Well, it's a good thing I keeled over that dog," Tom said. "It was the best object lesson I could give them."
And from then on there was no more trouble in this district about getting a supply of the medicinal bark.
A week passed and Professor Bumper was no nearer finding the lost city than he had been at first. Reluctantly, he returned to the tunnel camp to get more provisions.
"And then I'll start out again," he said.
"We'll go with you some other time," promised Tom. "But now I expect I'll have to get another blast ready."
He found the debris brought down by the second one all removed, and in a few days, preparations for exploding more of the powder were under way.
Many holes had been drilled in the face of the cliff of hard rock, and the charges tamped in. Electric wires connected them, and they were run out to the tunnel mouth where the switch was located.
This was done late one afternoon, and it was planned to set off the blast at the close of the working day, to allow all night for the fumes to be blown away by the current of air in the tunnel.
"Get the men out, Tim," said Tom, when all was ready.
"All right, sor," was the answer, and the Irish foreman went back toward the far end of the bore to tell the last shift of laborers to come out so the blast could be set off.
But in a little while Tim came running back with a queer look on his face.
"What's the matter?" asked Tom. "Why didn't you bring the men with you?"
"Because, sor, they're not there!"
"Not in the tunnel? Why, they were working there a little while ago, when I made the last connection!"
"I know they were, but they've disappeared."
"Disappeared?"
"Yis sir. There's no way out except at this end an' you didn't see thim come out: did you?"
"Then they've disappeared! That's all there is to it! Bad goin's on, thot's what it is, sor! Bad!" and Tim shook his head mournfully.
"There must be some mistake," said Tom, wondering if the Irish foreman were given to joking. Yet he did not seem that kind of man.
"Mistake? How can there be a mistake, sor? I wint in there to tell th' black imps t' come out, but they're not there to tell!"
"What's the trouble?" asked Job Titus, coming out of the office near the tunnel mouth. "What's wrong, Tom?"
"Why, I sent Tim in to tell the men to come out, as I was going to set off a blast, but he says the men aren't in there. And I'm sure the last shift hasn't come out."
By this time Koku, Mr. Damon and Walter Titus had come up to find out what the trouble was.
"The min have disappeared—that's all there is to it!" Tim said.
"Perhaps they have missed their way—the lights may have gone out, and they might have wandered into some abandoned cutting," suggested Tom.
"There aren't any abandoned cuttin's," declared Tim. "It's a straight bore, not a shaft of any kind. I've looked everywhere, and th' min aren't there I tell ye!"
"Are the lights going?" asked Job. "You might have missed them in the dark, Tim."
"The lights are going all right, Mr. Titus," said the young man in charge of the electrical arrangements. "The dynamo hasn't been stopped to-day."
"Come on, we'll have a look," proposed Walter Titus. "There must be some mistake. Hold back the blast, Tom."
"All right," and the young inventor disconnected the electrical detonating switch. "I'll come along and have a look too," he added. "Don't let anybody meddle with the wires, Jack," he said to the young Englishman who was in charge of the dynamo.
Into the dimly-lit tunnel advanced the party of investigators, with Tim Sullivan in the lead.
"Not a man could I find!" he said, murmuring to himself. "Not a man! An' I mind th' time in Oireland whin th' little people made vanish a whole village like this, jist bekase ould Mike Maguire uprooted a bed of shamrocks."
"That's enough of your superstitions, Tim," warned Job Titus. "If some of the other Indians hear you go on this way they'll desert as they did once before."
"Did they do that?" asked Tom.
"Yes, we had trouble that way when we first began the work. The place here was a howling wilderness then, and there were lots of pumas around.
"A puma is a small sized lion, you know, not specially dangerous unless cornered. Well, some of the men had their families here with them, and a couple of children disappeared. The story got started that there was a big puma—the king of them all—carrying off the little ones, and my brother and I awoke one morning to find every laborer missing. They departed bag and baggage. Afraid of the pumas."
"What did you do?"
"Well, we organized ourselves and our white helpers into a hunting party and killed a lot of the beasts. There wasn't any big one though."
"And what had become of the children?"
"They weren't eaten at all. They had wandered off into the woods, and some natives found them and took care of them. Eventually, they got back home. But it was a long while before we could persuade the Indians to come back. Since then we haven't had any trouble, and I don't want Tim, with his superstitious fancies, to start any."
"But the min are gone!" insisted the Irish foreman, who had listened to this story as he and the others walked along.
"We'll find them," declared Mr. Titus.
But though they looked all along the big shaft, and though the place was well lighted by extra lamps that were turned on when the investigation started, no trace could be found of the workmen, who had been left in the tunnel to finish tamping the blast charges. The party reached the rocky heading, in the face of which the powerful explosive had been placed, and not an Indian was in sight. Nor, as far as could be told, was there any side niche, or blind shaft, in which they could be hiding.
Sometimes, when small blasts were set off, the men would go behind a projecting shoulder of rock to wait until the charge had been fired, but now none was in such a refuge.
"It is queer," admitted Walter Titus. "Where can the men have gone?"
"That's what I want to know!" exclaimed Tim.
"Are you sure they didn't come out the mouth of the tunnel?" asked Job Titus.
"Positive," asserted Tom. I was there all the while, rigging up the fires."
"We'll call the roll, and check up," decided Job Titus. "Get Serato to help."
The Indian foreman had not been in the tunnel with the last shift of men, having left them to Tim Sullivan to get out in time. The Indian foreman was called from his supper in the shack where he had his headquarters, and the roll of workmen was called.
Ten men were missing, and when this fact became known there were uneasy looks among the others.
"Well," said Mr. Titus, after a pause. "The men are either in the tunnel or out of it. If they're in we don't dare set off the blast, and if they're out they'll show up, sooner or later, for supper. I never knew any of 'em to miss a meal."
"If such a thing were possible," said Walter Titus, "I would say that our rivals had a hand in this, and had induced our men to bolt in order to cripple our force. But we haven't seen any of Blakeson & Grinder's emissaries about, and, if they were, how could they get the ten men out of the tunnel without our seeing them? It's impossible!"
"Well, what did happen then?" asked Tom.
"I'm inclined to think that the men came out and neither you, nor any one else, saw them. They ran away for reasons of their own. We'll take another look in the morning, and then set off the blast."
And this was done. There being no trace of the men in the tunnel it was deemed safe to explode the charges. This was done, a great amount of rock being loosened.
The laborers hung back when the orders were given to go in and clean up. There were mutterings among them.
"What's the matter?" asked Job Titus.
"Them afraid," answered Serato. "Them say devil in tunnel eat um up! No go in."
"They won't go in, eh?" cried Tim Sullivan. "Well, they will thot! If there's a divil inside there's a worse one outside, an' thot's me! Git in there now, ye black-livered spalapeens!" and catching up a big club the Irishman made a rush for the hesitating laborers. With a howl they rushed into the tunnel, and were soon loading rock into the dump cars.
The mystery of the disappearance of the ten men—for mystery it was—remained, and as no side opening or passage could be found within the tunnel, it came to be the generally accepted explanation that the laborers had come out unobserved, and, for reasons of their own, had run away.
This habit on the part of the Peruvian workers was not unusual. In fact, the Titus brothers had to maintain a sort of permanent employment agency in Lima to replace the deserters. But they were used to this. The difference was that the Indians used to vanish from camp at night, and invariably after pay-day.
"And that's the only reason I have a slight doubt that they walked out of the tunnel," said Job Titus. "There was money due em."
"They never came out of the front entrance of the tunnel," said Tom. "Of that I'm positive."
But there was no way of proving his assertion.
The third blast, while not as successful as the second in the amount of rock loosened, was better than the first, and made a big advance in the tunnel progress. Tom was beginning to understand the nature of the mountain into which the big shaft was being driven and he learned how better to apply the force of his explosive.
That was the work which he had charge of—the placing of the giant powder so it would do the most effective work. Then, when the fumes from the blast had cleared away, in would surge the workmen to clear away the debris.
Under the direction of Mr. Swift, left at Shopton to oversee the manufacture of the explosive, new shipments came on promptly to Lima, and were brought out to the tunnel on the backs of mules, or in the case of small quantities, on the llamas. But the latter brutes will not carry a heavy load, lying down and refusing to get up if they are overburdened, whereas one has yet to find a mule's limit.
After his first success in getting the natives to take a more active interest in the gathering of the cinchona bark, Mr. Damon found it rather easy, for the story of Tom's electric rifle and how it had killed the mad dog spread among the tribes, and Mr. Damon had but to announce that the "lightning shooter," as Tom was called, was a friend of the drug concern to bring about the desired results. Mr. Damon, by paying a sort of bribe, disguised under the name "tax," secured the help of Peruvian officials so he had no trouble on that score.
Koku was in his element. He liked a wild life and Peru was much more like the country of giants where Tom had found him, than any place the big man had since visited. Koku had great strength and wanted to use it, and after a week or so of idleness he persuaded Tom to let him go in the tunnel to work.
The giant was made a sort of foreman under Tim, and the two became great friends. The only trouble with Koku was that he would do a thing himself instead of letting his men do it, as, of course, all proper foremen should do. If the giant saw two or three of the Indians trying to lift a big rock into the little dump cars, and failing because of its great weight, he would good-naturedly thrust them aside, pick up the big stone in his mighty arms, and deposit it in its place.
And once when an unusually big load had been put in a car, and the mule attached found it impossible to pull it out to the tunnel mouth, Koku unhitched the creature and, slipping the harness around his waist, walked out, dragging the load as easily as if pulling a child on a sled.
Professor Bumper kept on with his search for the lost city of Pelone. Back and forth he wandered among the wild Andes Mountains, now hopeful that he was on the right trail, and again in despair. Tom and Mr. Damon went with him once more for a week, and though they enjoyed the trip, for the professor was a delightful companion, there were no results. But the scientist would not give up.
Tom Swift was kept busy looking after the shipments of the explosive, and arranging for the blasts. He had letters from Ned Newton in which news of Shopton was given, and Mr. Swift wrote occasionally. But the mails in the wilderness of the Andes were few and far between.
Tom wrote a letter of explanation to Mr. Nestor, in addition to the wireless he had sent regarding the box labeled dynamite, but he got no answer. Nor were his letters to Mary answered.
"I wonder what's wrong?" Tom mused. "It can't be that they think I did that on purpose. And even if Mr. Nestor is angry at me for something that wasn't my fault, Mary ought to write."
But she did not, and Tom grew a bit despondent as the days went by and no word came.
"I suppose they might be offended because I left Rad to do up that package instead of attending to it myself," thought Tom. "Well, I did make a mistake there, but I didn't mean to. I never thought about Eradicate's not reading. I'll make him go to night school as soon as I get back. But maybe I'll never get another chance to send Mary anything. If I do, I'll not let Rad deliver it—that's sure."
The feeling of alarm engendered among the Indians by the disappearance of their ten fellow-workers seemed to have disappeared. There were rumors that some of the mysterious ten had been seen in distant villages and settlements, but the Titus brothers could not confirm this.
"I don't think anything serious happened to them, anyhow," said Job Titus one day. "And I should hate to think our work was responsible for harm to any one."
"Your rivals don't seem to be doing much to hamper you," observed Tom. "I guess Waddington gave up.
"I won't be too sure of that," said Mr. Titus.
"Why, what has happened?" Tom asked.
"Well, nothing down here—that is, directly—but we are meeting with trouble on the financial end. The Peruvian government is holding back payments."
"Why is that?"
"They claim we are not as far advanced as we ought to be."
"Aren't you?"
"Practically, yes. There was no set limit of work to be done for the intermediate payments. We bonded ourselves to have the tunnel done at a certain date.
"If we fail, we lose a large sum, and if we get it done ahead of time we get a big premium. There was no question as to completing a certain amount of footage before we received certain payments. But Senor Belasdo, the government representative, claims that we will not be done in time, and therefore he is holding back money due us. I'm sure the rival contractors have set him up to this, because he was always decent to us before.
"Another matter, too, makes me suspicious. We have tried to raise money in New York to tide us over while the government is holding up our funds here. But our New York office is meeting with difficulties. They report there is a story current to the effect that we are going to fail, and while that isn't so, you know how hard it is to borrow money in the face of such rumors. We are doing all we can to fight them, of course, and maybe we'll beat out our rivals yet.
"But that isn't all. I'm sure some one is on the ground here trying to make trouble among our workers. I never knew so many men to leave, one after another. It's keeping the employment agency in Lima busy supplying us with new workers. And so many of them are unskilled. They aren't able to do half the work of the old men, and poor Tim Sullivan is in despair."
"You think some one here is causing dissensions and desertions among your men?"
"I'm sure of it! I've tried to ferret out who it is, but the spy, for such he must be, keeps his identity well hidden."
Tom thought for a moment. Then he said:
"Mr. Titus, with your permission, I'll see if I can find out about this for you."
"Find out what, Tom?"
"What is causing the men to leave. I don't believe it's the scare about the ten missing ones."
"Nor do I. That's past and gone. But how are you going to get at the bottom of it?"
"By keeping watch. I've got nothing to do now for the next week. We've just set off a big blast, and I've got the powder for the following one all ready. The men will be busy for some time getting out the broken rock. Now what I propose to do is to go in the tunnel and work among them until I can learn something.
"I can understand the language pretty well now, though I can't speak much of it. I'll go in the tunnel every day and find out what's going on."
"But you'll be known, and if one of our men, or one who we suppose is one, turns out to be a spy, he'll be very cautious while you're in there."
"He won't know me," Tom said. "This is how I'll work it. I'll go off with Professor Bumper the next time he starts on one of his weekly expeditions into the woods. But I won't go far until I turn around and come back. I'll adopt some sort of disguise, and I'll apply to you for work. You can tell Tim to put me on. You might let him into the secret, but no one else."
A few days later Tom was seen departing with Professor Bumper into the interior, presumably to help look for the lost city. Mr. Damon was away from camp on business connected with the drug concern, and Koku, to his delight, had been given charge of a stationary hoisting engine outside the tunnel, so he would not come in contact with Tom. It was not thought wise to take the giant into the secret.
Then one day, shortly after Professor Bumper and Tom had disappeared into the forest, a ragged and unkempt white man applied at the tunnel camp for work. There was just the barest wink as he accosted Mr. Titus, who winked in turn, and then the new man was handed over to Tim Sullivan, as a sort of helper.
And so Tom Swift began his watch.
Left to himself, with only the rather silent gang of Peruvian Indians as company, Tom Swift looked about him. There was not much active work to be done, only to see that the Indians filled the dump cars evenly full, so none of the broken rock would spill over the side and litter the tramway. Then, too, he had to keep the Indians up to the mark working, for these men were no different from any other, and they were just as inclined to "loaf on the job" when the eye of the "boss" was turned away.
They did not talk much, murmuring among themselves now and then, and little of what they said was intelligible to Tom. But he knew enough of the language to give them orders, the main one of which was:
"Hurry up!"
Now, having seen to it that the gang of which he was in temporary charge was busily engaged, Tom had a chance to look about him. The tunnel was not new to him. Much of his time in the past month had been spent in its black depths, illuminated, more or less, by the string of incandescent lights.
"What I want to find," mused Tom, as he walked to and fro, "is the place where those Indians disappeared. For I'm positive they got away through some hole in this tunnel. They never came out the main entrance."
Tom held to this view in spite of the fact that nearly every one else believed the contrary—that the men had left by the tunnel mouth, near which Tom happened to be alone at the time.
Now, left to himself, with merely nominal duties, and so disguised that none of the workmen would know him for the trim young inventor who oversaw the preparing of the blast charges, Tom Swift walked to and fro, looking for some carefully hidden passage or shaft by means of which the men had got away.
"For it must be well hidden to have escaped observation so long," Tom decided. "And it must be a natural shaft, or hole, for we are boring into native rock, and it isn't likely that these Indians ever tried to make a tunnel here. There must be some natural fissure communicating with the outside of the mountain, in a place where no one would see the men coming out."
But though Tom believed this it was another matter to demonstrate his belief. In the intervals of seeing that the natives properly loaded the dump cars, and removed as much of the debris as possible, Tom looked carefully along the walls and roof of the tunnel thus far excavated.
There were cracks and fissures, it is true, but they were all superficial ones, as Tom ascertained by poking a long pole up into them.
"No getting out that way," he said, as he met with failure after failure.
Once, while thus engaged, he saw Serato, the Indian foreman looking narrowly at him, and Serato said something in his own language which Tom could not understand. But just then along came Tim Sullivan, who, grasping the situation, exclaimed:
"Thot's all roight, now, Serri, me lad!" for thus he contracted the Indian's name. "Thot's a new helper I have, a broth of a bye, an' yez kin kape yer hands off him. He's takin' orders from me!"
"Um!" grunted the Indian. "Wha for he fish in tunnel roof?" for Tom's pole was one like those the Indians used when, on off days, they emulated Izaak Walton.
"Fishin' is it!" exclaimed Tim. "Begorra 'tis flyin' fish he's after I'm thinkin'. Lave him alone though, Serri! I'm his boss!"
"Um!" grunted the Indian again, as he moved off into the farther darkness.
"Be careful, Tom," whispered the Irishman, when the native had gone. "These black imps is mighty suspicious. Maybe thot fellah had a hand in th' disappearances hisself."
"Maybe," admitted Tom. "He may get a percentage on all new hands that are hired."
Tom kept on with his search, always hoping he might find some hidden means of getting out of the tunnel. But as the days went by, and he discovered nothing, he began to despair.
"The queer thing about it," mused Tom, "is what has become of the ten men. Even if they did find some secret means of leaving, what has become of them? They couldn't completely disappear, and they have families and relatives that would make some sort of fuss if they were out of sight completely this long. I wonder if any inquiries have been made about them?"
When Tom came off duty he asked the Titus brothers whether or not any of the relatives of the missing men had come to seek news about them. None had.
"Then," said Tom, "you can depend on it the men are all right, and their relatives know it. I wonder how it would do to make inquiries at that end? Question some of the relatives."
"Bless my hat band!" exclaimed Mr. Damon, who was at the conference. "I never thought of that. I'll do it for you."
The odd man had gotten his quinine gathering business well under way now, and he had some spare time. So, with an interpreter who could be trusted, he went to the native village whence had come nearly all of the ten missing men. But though Mr. Damon found some of their relatives, the latter, with shrugs of their shoulders, declared they had seen nothing of the ones sought.
"And they didn't seem to worry much, either," reported Mr. Damon.
"Then we can depend on it," remarked Tom, "that the men are all right and their relatives know it. There's some conspiracy here."
So it seemed. But who was at the bottom of it?
"I can't figure out where Blakeson & Grinder come in," said Job Titus. "They would have an object in crippling us, but they seem to be working from the financial end, trying to make us fail there. I haven't seen any of their sneaking agents around here lately, and as for Waddington he seems to have stayed up North."
Tom resumed his vigil in the tunnel, poking here and there, but with little success. His week was about up, and he would soon have to resume his character as powder expert, for the debris was nearly all cleaned up, and another blast would have to be fired shortly.
"Well, I'm stumped!" Tom admitted, the day when he was to come on duty for the last time as a pretended foreman. "I've hunted all over, and I can't find any secret passage."
It was warm in the tunnel, and Tom, having seen one train of the dump cars loaded, sat down to rest on an elevated ledge of rock, where he had made a sort of easy chair for himself, with empty cement bags for cushions.
The heat, his weariness and the monotonous clank-clank of a water pump near by, and the equally monotonous thump of the lumps of rocks in the cars made Tom drowsy. Almost before he knew it he was asleep.
What suddenly awakened him he could not tell. Perhaps it was some influence on the brain cells, as when a vivid dream causes us to start up from slumber, or it may have been a voice. For certainly Tom heard a voice, he declared afterward.
As he roused up he found himself staring at the rocky wall of the tunnel. And yet the wall seemed to have an opening in it and in the opening, as if it were in the frame of a picture, appeared the face Tom had seen at his library the day Job Titus called on him—the face of Waddington!
Tom sat up so quickly that he hit his head sharply on a projecting rock spur, and, for the moment he "saw stars." And with the appearance of these twinkling points of light the face of Waddington seemed to fade away, as might a vision in a dream.
"Bless my salt mackerel, as Mr. Damon would say!" cried Tom. "What have I discovered?"
He rubbed his head where he had struck it, and then passed his hand before his eyes, to make sure he was awake. But the vision, if vision it was, had vanished, and he saw only the bare rock wall. However, the echo of the voice remained in his ears, and, looking down toward the tunnel floor Tom saw Serato, the Indian foreman.
"Were you speaking to me?" asked Tom, for the man understood and spoke English fairly well.
"No, sar. I not know you there!" and the foreman seemed startled at seeing Tom. Clearly he was in a fright.
"You were speaking!" insisted Tom.
"No, sar!" The man shook his head.
"To some one up there!" went on the young inventor, waving his hand toward the spot where he had seen the face in the rock.
"Me speak to roof? No, sar!" Serato laughed.
Tom did not know what to believe.
"You hear me tell um lazy man to much hurry," the Indian went on. "Me not know you sleep there, sar!"
"Oh, all right," Tom said, recollecting that he must keep up his disguise. "Maybe I was dreaming."
"Yes, sar," and the foreman hurried on, with a backward glance over his shoulder.
"Now was I dreaming or not?" thought Tom. "I'm going to have a look at that place though, where I saw Waddington's face. Or did I imagine it?"
He got a long pole and a powerful flash lamp, and when he had a chance, unobserved, he poked around in the vicinity where he had seen the face.
But there was only solid rock.
"It must have been a dream," Tom concluded. "I've been thinking too much about this business. I'll have to give up. I can't solve the mystery of the missing men."
The next day, much disappointed, he resumed his own character as explosive expert, and prepared for another blast. The net result of his watch was that he became suspicious of Serato, and so informed the Titus Brothers.
"Oh, but you're mistaken," said Job. "We have had him for years, on other contracts in Peru, and we trust him."
"Well, I don't," Tom said, but he had to let it go at that.
Another blast was set off, but it was not very successful.
"The rock seems to be getting harder the farther in we go," commented Walter Titus. "We're not up to where we ought to be."
"I'll have to look into it," answered Tom. "I may have to change the powder mixture. Guess I'll go up the mountain a way, and see if there are any outcroppings of rock there that would give me an idea of what lies underneath."
Accordingly, while the men in the tunnel were clearing away the rock loosened by the blast, Tom, one day, taking his electric rifle with him, went up the mountain under which the big bore ran.
He located, by computation, the spot beneath which the end of the tunnel then was, and began collecting samples of the outcropping ledge. He wanted to analyze these pieces of stone later. Koku was with him, and, giving the giant a bag of stones to carry, Tom walked on rather idly.
It was a wild and desolate region in which he found himself on the side of the mountain. Beyond him stretched towering and snow-clad peaks, and high in the air were small specks, which he knew to be condors, watching with their eager eyes for their offal food.
As Tom and Koku made their way along the mountain trail they came unexpectedly upon an Indian workman who was gathering herbs and bark, an industry by which many of the natives added to their scanty livelihood. The woman was familiar with the appearance of the white men, and nodded in friendly fashion.
Tom passed on, thinking of many things, when he was suddenly startled by a scream from the woman. It was a scream of such terror and agony that, for the moment, Tom was stunned into inactivity. Then, as he turned, he saw a great condor sweeping down out of the air, the wind fairly whistling through the big, outstretched wings.
"Jove!" ejaculated Tom. "Can the bird be going to attack the woman?"
But this was not the object of the condor. It was aiming to strike, with its fierce talons, at a point some paces distant from where the woman stood, and in the intervals between her screams Tom heard her cry, in her native tongue:
"My baby! My baby! The beast-bird will carry off my baby!"
Then Tom understood. The woman herb-gatherer had brought her infant with her on her quest, and had laid it down on a bed of soft grass while she worked. And it was this infant, wrapped as Tom afterward saw in a piece of deer-skin, at which the condor was aiming.
"Master shoot!" cried Koku, pointing to the down-sweeping bird.
"You bet I'll shoot!" cried Tom.
Throwing his electric rifle to his shoulder, Tom pressed the switch trigger. The unseen but powerful force shot straight at the condor.
The outstretched wings fell limp, the great body seemed to shrivel up, and, with a crash, the bird fell into the underbrush, breaking the twigs and branches with its weight. The electric rifle, a full account of which was given in the volume entitled "Tom Swift and His Electric Rifle," had done its work well.
With a scream, in which was mingled a cry of thanks, the woman threw herself on the sleeping child. The condor had fallen dead not three paces from it.
Tom Swift had shot just in time.