"Come on!" cried Blake to Joe.

"I'm with you," was the reply.

"And I, also," said Mr. Alcando with set teeth.

Fortunately for them the tug was tied to a temporary dock on the side of the hill where the slide had started, so they did not have to take a boat across, but could at once start for the scene of the disaster.

"We may not be here when you come back!" called Captain Wiltsey after the boys.

"Why not?" asked Joe.

"I may have to go above or below. I don't want to take any chances of being caught by a blockade."

"All right. We'll find you wherever you are," said Blake.

As yet the mass of slipping and sliding earth was falling into the waters of the Canal some distance from the moored tug. But there was no telling when the slide might take in a larger area, and extend both east and west.

Up a rude trail ran Blake and Joe, making their way toward where the movement of earth was most pronounced. The light was not very good on account of the rain, but they slipped into the cameras the most sensitive film, to insure good pictures even when light conditions were most unsatisfactory.

The moving picture boys paused for only a glance behind them. They had heard the emergency orders being given. Soon they would be flashed along the whole length of the Canal, bringing to the scene the scows, the dredges, the centrifugal pumps—the men and the machinery that would tear out the earth that had no right to be where it had slid.

Then, seeing that the work of remedying the accident was under way, almost as soon as the accident had occurred, Blake and Joe, followed by Mr. Alcando, hurried on through the rain, up to their ankles in red mud, for the rain was heavy. It was this same rain that had so loosened the earth that the slide was caused.

"Here's a good place!" cried Blake, as he came to a little eminence that gave a good view of the slipping, sliding earth and stones.

"I'll go on a little farther," said Joe. "We'll get views from two different places."

"What can I do?" asked the Spaniard, anxious not only to help his friends, but to learn as much as he could of how moving pictures are taken under adverse circumstances.

"You stay with Blake," suggested Joe. "I've got the little camera and I can handle that, and my extra films, alone and with ease. Stay with Blake."

It was well the Spaniard did.

With a rush and roar, a grinding, crashing sound a large mass of earth, greater in extent than any that had preceded, slipped from the side of the hill.

"Oh, what a picture this will make!" cried Blake, enthusiastically.

He had his camera in place, and was grinding away at the crank, Mr. Alcando standing ready to assist when necessary.

"Take her a while," suggested Blake, who was "winded" from his run, and carrying the heavy apparatus.

The big portion of the slide seemed to have subsided, at least momentarily. Blake gave a look toward where Joe had gone. At that moment, with a roar like a blast of dynamite a whole section of the hill seemed to slip away and then, with a grinding crash the slanting earth on which Joe stood, and where he had planted the tripod of his camera, went out from under him.

Joe and his camera disappeared from sight.



CHAPTER XX

AT GATUN DAM

"Look!" cried Mr. Alcando. He would have said more—have uttered some of the expressions of fear and terror that raced through his mind, but he could not speak the words. He could only look and point.

But Blake, as well as the Spaniard, had seen what had happened, and with Blake to see was to act.

"Quick!" he cried. "We've got to get him out before he smothers! Pack up this stuff!"

As he spoke he folded the tripod legs of his camera, and laid it on top of a big rock, that seemed firmly enough imbedded in the soil not to slip from its place. Then, placing beside it the spare boxes of film, and throwing over them a rubber covering he had brought, Blake began to run across the side of the hill toward the place where Joe had last been seen.

"Come on!" cried Blake to Mr. Alcando, but the Spaniard needed no urging. He had laid with Blake's the boxes of film he carried, and the two were now speeding to the rescue.

"Go get help!" cried Joe to an Indian worker from the tug, who had followed to help carry things if needed. "Go quick! Bring men—shovels! We may have to dig him out," he added to Mr. Alcando.

"If—if we can find him," replied the other in low tones.

"Go on—run!" cried Joe, for the Indian did not seem to understand. Then the meaning and need of haste occurred to him.

"Si, senor, I go—pronto!" he exclaimed, and he was off on a run.

Fortunately for Blake and Mr. Alcando, the worst of the slide seemed to be over. A big mass of the hill below them, and off to their right, had slid down into the Canal. It was the outer edge of this that had engulfed Joe and his camera. Had he been directly in the path of the avalanche, nothing could have saved him. As it was, Blake felt a deadly fear gripping at his heart that, after all, it might be impossible to rescue his chum.

"But I'll get him! I'll get him!" he said fiercely to himself, over and over again. "I'll get him!"

Slipping, sliding, now being buried up to their knees in the soft mud and sand, again finding some harder ground, or shelf of shale, that offered good footing, Blake and the Spaniard struggled on through the rain. It was still coming down, but not as hard as before.

"Here's the place!" cried Blake, coming to a halt in front of where several stones formed a rough circle. "He's under here."

"No, farther on, I think," said the Spaniard.

Blake looked about him. His mind was in a turmoil. He could not be certain as to the exact spot where Joe had been engulfed in the slide, and yet he must know to a certainty. There was no time to dig in many places, one after the other, to find his chum. Every second was vital.

"Don't you think it's here?" Blake asked, "Try to think!"

"I am!" the Spaniard replied. "And it seems to me that it was farther on. If there was only some way we could tell—"

The sentence trailed off into nothingness. There was really no way of telling. All about them was a dreary waste of mud, sand, boulders, smaller stones, gravel and more mud—mud was over everything. And more mud was constantly being made, for the rain had not ceased.

"I'm going to dig here!" decided Blake in desperation, as with his bare hands he began throwing aside the dirt and stones. Mr. Alcando watched him for a moment, and then, as though giving up his idea as to where Joe lay beneath the dirt, he, too, started throwing on either side the clay and soil.

Blake glanced down the hill. The Indian messenger had disappeared, and, presumably, had reached the tug, and was giving the message for help. Then Blake bent to his Herculean task again. When next he looked up, having scooped a slight hole in the side of the hill, he saw a procession of men running up—men with picks and shovels over their shoulders. He saw, too, a big slice of the hill in the Canal. The wonderful waterway was blocked at Culebra Cut.

Blake thought little of that then. His one idea and frantic desire was to get Joe out.

"They'll never get here in time," said Mr. Alcando in a low voice. "We'll never get him out in time."

"We—we must!" cried Blake, as again he began digging.

Mr. Alcando had spoken the truth. The men could not get there in time—Joe could not be dug out in time—if it had depended on human agencies. For not only was Blake unaware of the exact spot where his chum lay buried, but, at least so it seemed, there had been such a mass of earth precipitated over him that it would mean hours before he could be gotten out.

However, fate, luck, Providence, or whatever you choose to call it, had not altogether deserted the moving picture boys. The very nature of the slide, and the hill on which it had occurred, was in Joe's favor. For as Blake, after a despairing glance at the approaching column of men, bent again to his hopeless task, there was a movement of the earth.

"Look out!" cried Mr. Alcando.

He would have spoken too late had what happened been of greater magnitude. As it was Blake felt the earth slipping from beneath his feet, and jumped back instinctively. But there was no need.

Beyond him another big slide had occurred, and between him and Mr. Alcando, and this last shift of the soil, was a ridge of rocks that held them to their places.

Down in a mass of mud went another portion of the hill, and when it had ceased moving Blake gave a cry of joy. For there, lying in a mass of red sand, was Joe himself, and beside him was the camera, the tripod legs sticking out at grotesque angles.

"Joe! Joe!" yelled Blake, preparing to leap toward his chum.

"Be careful!" warned Mr. Alcando. "There may be danger—"

But no known danger could have held Blake back.

"He is there!" Blake cried. "We were digging in the wrong place."

"I thought so," said the Spaniard. But Blake did not stay to listen to him. Now he was at Joe's side. The slide had laid bare a ledge of rock which seemed firm enough to remain solid for some time.

"Joe! Joe!" cried Blake, bending over his chum. And then he saw what it was that had probably saved Joe's life. The boy's big rubber coat had been turned up and wound around his head and face in such a manner as to keep the sand and dirt out of his eyes, nose and mouth. And, also wrapped up in the folds of the garment, was the camera.

Rapidly Blake pulled the coat aside. Joe's pale face looked up at him. There was a little blood on the forehead, from a small cut. The boy was unconscious.

"Joe! Joe!" begged Blake. "Speak to me! Are you all right?"

He bared his chum's face to the pelting rain—the best thing he could have done, for it brought Joe back to consciousness—slowly at first, but with the returning tide of blood the fainting spell passed.

"We must get him to the boat," said Mr. Alcando, coming up now.

"Are you hurt? Can you walk?" asked Blake.

Joe found his voice—though a faint voice it was.

"Yes—yes," he said, slowly. "I—I guess I'm all right."

There seemed to be no broken bones. Mr. Alcando took charge of the camera. It was not damaged except as to the tripod.

"What happened?" asked Joe, his voice stronger now.

"You were caught in the slide," Blake informed him. "Don't think about it now. We'll have you taken care of."

"I—I guess I'm all right," Joe said, standing upright. "That coat got wound around my face, and kept the dirt away. I got a bad whack on the head, though, and then I seemed to go to sleep. Did I get any pictures?"

"I don't know. Don't worry about them now."

"We—we missed the best part of the slide, I guess," Joe went on. "Too bad."

"It's all right!" his chum insisted. "I was filming away up to the time you went under. Now, let's get back."

By this time the crowd of men, including Captain Wiltsey, had arrived. But there was nothing for them to do. The slide had buried Joe, and another slide had uncovered him, leaving him little the worse, save for a much-muddied suit of clothes, and a bad headache, to say nothing of several minor cuts and bruises. It was a lucky escape.

Back to the tug they went, taking the cameras with them. Joe was given such rough and ready surgery and medical treatment as was available, and Captain Wiltsey said he would leave at once for Gatun, where a doctor could be obtained.

Fortunately the blockading of the Canal by the slide did not stop the Bohio from continuing her journey. The slide was north of her position.

"I do hope we got some good films," said Joe, when he had been made as comfortable as possible in his berth.

"I think we did," Blake said. "Your camera was protected by the rubber coat, and mine wasn't hurt at all."

Later the boys learned that though they had missed the very best, or rather the biggest, part of the slide, still they had on their films enough of it to make a most interesting series of views.

Late that afternoon Joe was in the care of a physician, who ordered him to stay in bed a couple of days. Which Joe was very willing to do. For, after the first excitement wore off, he found himself much more sore and stiff than he had realized.

They were at Gatun now, and there Blake planned to get some views of the big dam from the lower, or spillway side.

"But first I'm going back to the slide," he said. "I want to get some views of the dredgers getting rid of the dirt."



CHAPTER XXI

MR. ALCANDO'S ABSENCE

Blake spent a week at Culebra Cut, making pictures of the removal of the great mass of earth that had slid into the water. The chief engineer, General George W. Goethals, had ordered every available man and machine to the work, for though the Canal had not been formally opened, many vessels had started to make trips through it, and some of them had been blocked by the slide. It was necessary to get the dirt away so they could pass on their voyage.

So with dredges, with steam shovels, and hydraulic pumps, that sucked through big flexible pipes mud and water, spraying it off to one side, the work went on. Blake had Mr. Alcando to help him, and the Spaniard was now expert enough to render valuable assistance. While Blake was at one scene, getting views of the relief work, his pupil could be at another interesting point.

Blake had telegraphed to New York that the one picture above all others desired had been obtained—that of a big slide in the Culebra Cut. He did not tell how Joe had nearly lost his life in helping get the films, for Blake was modest, as was his chum, and, as he said, it was "all in the day's work."

Joe was left to recover from the shock and slight injuries at Gatun, while Blake and Mr. Alcando were at Culebra. For the shock to the young moving picture operator had been greater than at first supposed, though his bodily injuries were comparatively slight.

"Well, what's next on the programme?" asked Joe of Blake, about two weeks after the accident, when Blake had returned from Culebra. Most of the work there was done, and the Canal was again open, save to vessels of extreme draught.

"I guess we'll go on making pictures of Gatun Dam now; that is, if you're well enough," spoke Blake. "How do you feel?"

"Pretty fair. How did Alcando make out?"

"All right. He's learning fast. We can trust him with a camera now, out alone."

"That's good. I say, Blake," and Joe's voice took on a confidential tone, "you haven't noticed anything strange about him, have you?"

"Strange? What do you mean?"

"I mean while he was off there with you. Anything more about that alarm clock of his? And did anything more develop about his knowing the captain of that vessel that sunk the Nama?"

"No, that was only coincidence, I think. Why, I can't say that I've noticed anything suspicious about him, Joe, if that's what you mean," and Blake's voice had a questioning tone.

"That's what I do mean," spoke Joe. "And if you haven't I have."

"Have what?"

"I've been watching Alcando since you and he came back, and I think he's decidedly queer."

"Suspicious, you mean?"

"I mean he acts as though something were going to happen."

"Another landslide?" asked Blake with a laugh. "No chance of that here at Gatun Dam."

"No, but something else could happen, I think."

"You mean the—dam itself?" asked Blake, suddenly serious.

"Well, I don't exactly know what I do mean," Joe said, and his voice was troubled. "I'll tell you what I noticed and heard, and you can make your own guess."

"Go on," invited Blake. "I'm all ears, as the donkey said."

"It's no laughing matter," retorted his chum. "Haven't you noticed since you and Alcando came back," he went on, "that he seems different, in a way. He goes about by himself, and, several times I've caught him looking at the dam as though he'd never seen it before. He is wonderfully impressed by it."

"Well, anybody would be," spoke Blake. "It's a wonderful piece of engineering. But go on."

"Not only that," resumed Joe, "but I've heard him talking to himself a lot."

"Well, that's either a bad sign, or a good one," laughed his chum. "They say when a fellow talks to himself he either has money in the bank, or he's in love. You can take your choice."

"Not when it's the kind of talk I overheard Alcando having with himself," Joe resumed. "I went out on the dam yesterday, and I saw him looking at it. He didn't see me, but I heard him muttering to himself."

"What did he say?" Blake wanted to know.

"I didn't hear it all," was Joe's answer, "but I caught two sentences that made me do a lot of thinking. They were these: 'I just hate to do it, though I'll have to, I suppose. But I'll not put the blame on'—" and Joe came to a pause.

"Well, go on," urged Blake.

"That's all there was," Joe continued. "I couldn't hear any more. What do you suppose he meant?"

"He might have meant nothing—or anything," Blake remarked slowly. "It sounds to me as though he meant that he had made a failure of the moving picture business, and was going to quit. That must be it. He meant that he had to give it up, though he hated to, and that he wouldn't blame us for not giving him better instruction."

"Could he have meant that?"

"He could," Blake replied, "for, to tell you the truth, he'll never be a good operator. He hasn't a correct eye for details, and he can't focus worth a cent, though that might be overcome in time. He does well enough for ordinary work, but when it comes to fine details he isn't in it. I found that out back there at Culebra when he was working with me. Of course he was a lot of help, and all that, but he's a failure as a moving picture operator."

"I'm sorry to hear that," said Joe, with genuine sympathy.

"So am I to have to come to that conclusion," Blake went on. "I guess he knows it, too, for he said as much to me. So I guess that's what his talking to himself meant."

"Perhaps it did. Well, we did our best for him."

"We surely did, and I guess he appreciates that. He said so, anyhow."

"And so you're going to get some Gatun pictures and then quit—eh?"

"That's it, Joe, and the sooner we get them the sooner we can get back home. I've had all I want of Panama. Not that it isn't a nice place, but we've seen all there is to see."

"We might try a little more of the jungle."

"We got enough of those pictures before," Blake declared. "No, the dam will wind it up, as far as we're concerned."

If Mr. Alcando felt any sorrow over his failure as a moving picture operator he did not show it when next he met the boys. He was quite cheerful.

"Are you fully recovered, Joe?" he asked.

"Oh, sure! I'm all right again."

"I only wish I could have had a hand in rescuing you," the Spaniard went on. "It would have been a manner of paying, in a slight degree, the debt I owe you boys. But fate took that out of my hands, and you were saved by the same sort of slide that covered you up."

"Yes, I guess I was born lucky," laughed Joe.

Preparations for taking several views of the big Gatun Dam from the lower, or spillway side, were made. One afternoon Mr. Alcando asked if he would be needed in making any views, and when Blake told him he would not, the Spaniard went off by himself, taking a small camera with him.

"I'm going to try my luck on my own hook," he said.

"That's right," encouraged Blake. "Go it on your own responsibility. Good luck!"

"He's trying hard, at all events," said Joe, when their acquaintance had left them.

"Yes," agreed Joe. "He wants to make good."

Several times after this Mr. Alcando went off, by himself for more or less prolonged absences. Each time he took a camera with him.

It was a small machine, made more for amateurs than for professionals, but it gave good practice.

"How are you coming on?" asked Blake one day, when Mr. Alcando returned after a trip which, he said, had taken him to Gatun Dam.

"Oh, pretty well, I think," was the answer, as the Spaniard set down his camera and carrying case. "I got some good scenes, I believe. When are you going to make the last of the spillway views?"

Blake did not answer. He was listening to a curious sound. It was a ticking, like that of an alarm clock, and it came from the interior of the carrying case that held extra reels of film for the little camera Mr. Alcando had.

Blake felt himself staring at the black box.



CHAPTER XXII

A WARNING

"What is the matter?" asked Mr. Alcando, as he noted Blake's intent look. "Is something—?" He did not finish.

"That sound—in the film-case—" began Blake.

"Oh, my alarm clock—yes!" exclaimed the Spaniard. "I take it out with me on my trips. Often, when I have finished taking pictures, I try to do a little work on it. There is one feature I can't seem to perfect, and I hope some day to stumble on it. Without it the clock is a failure. I had it with me to-day, but I could make no progress—none at all. I think I shall put it away again," and taking with him the case, from which came that curious ticking noise, he went to his stateroom.

Blake shook his head. He did not know what to think.

"He'll never make a good moving picture operator," he said to himself. "You've got to give your whole mind to it, and not be monkeying with inventions when you set out to get views. An alarm clock!

"Suppose he does perfect it? There are enough on the market now, and I don't believe there's a fortune in any of 'em. He might much better stick to what he set out to learn. Well, it isn't any of my business, I suppose. Joe and I have done all we can."

Several times after this the Spaniard went off by himself, to make simple moving picture views with the little camera. But, whether or not he took along the curious brass-bound box, with the metal projections, which he said was an alarm clock, was something Blake or Joe could not discover. For Blake had told Joe of Alcando's confession.

Certainly if Alcando did take his model with him, he did not wind it up until leaving the boys, for no ticking sound came from the case.

The Canal was now as it had been before the big slide. Vessels were passing to and fro, though in some parts of the waterway much finishing work remained to be done. Blake and Joe took some views of this, and also "filmed" the passage of the various ships to make their pictures of wider appeal when they would be shown at the Panama Exposition. Mr. Alcando did his share, and, for a time seemed to show a great interest in his work, so that Blake had hopes the Spaniard would really become a good operator. But something was always lacking, and it was not altogether effort on the part of the pupil.

The time was approaching when Blake and Joe must bring their work to an end. They had accomplished what they set out to do, and word came back from New York, where their films had been sent for development, that they were among the best the boys had ever taken.

"Well, I will soon be leaving you," said Mr. Alcando to the chums, one day. "I have heard from my railroad firm, and they are anxious for me to come back and begin making pictures there."

"His friends are going to be sadly disappointed in him," thought Blake. "It's too bad. He'll make a failure of those views. Well, if he does they may send for Joe and me, and that will be so much more business for us, though I'm sorry to see him make a fizzle of it."

But Mr. Alcando appeared to have no fears on his own account. He was cheerfully optimistic.

"I shall want several cameras, of different kinds," he said to the boys. "Perhaps you can recommend to me where to get some."

"Yes," spoke Joe. "We'll help you pick them out if you are going back to New York."

"I am not so sure of that," the Spaniard said. "I will know in a few days when I hear from my railroad friends. I expect a letter shortly."

There was some little delay in getting the pictures Blake wanted of the Gatun Dam. Certain work had to be done, and Blake wanted to show the complete and finished structure. So he decided to wait.

About a week after the above conversation with Mr. Alcando, the Spaniard came to the boys, waving an open letter in his hand. The mail had just come in, bringing missives to Blake and Joe. Some were of a business nature, but for each boy there was an envelope, square and of delicate tint—such stationery as no business man uses. But we need not concern ourselves with that. We all have our secrets.

"I have my marching orders," laughed the Spaniard. "I leave you this week, for my own particular jungle. Now I must arrange to get my cameras."

"We'll help you," offered Joe, and then, with the catalogue of a moving picture supply house before them, the boys sat down to plan what sort of an outfit would best be suited to the needs of Mr. Alcando. He was not limited as to money, it was evident, for he picked out the most expensive cameras possible to buy.

"I wish you boys would come and see me, when I get to work taking views along our railroad line," he said. "It isn't altogether a selfish invitation," he added with a laugh, "for I expect you could give me good advice, and correct some of my mistakes."

"I'm afraid we won't get a chance to go to South America," Blake answered.

With a tentative list of what he needed, Mr. Alcando went to write a letter to his railroad officials, asking them to order his outfit for him.

As Blake pushed back his chair, intending to leave the cabin to seek his own stateroom, he saw, on the floor, a piece of paper. Idly he picked it up, and, as he saw it was part of a letter to the Spaniard he folded it, to hand to him. But, as he did so he caught sight of a few words on it. And those words made him stare in wonder. For Blake read:

"Stuff is all ready for you. You had better do the job and get away. There is some fine scenery in Europe."

Saying nothing to his chum about it, Blake went with the letter toward the Spaniard's stateroom. He was not in, but Blake put the paper on a desk, with some others, and came out hastily.

"I wonder what that meant?" he thought to himself. "That must have been his orders to come back to Brazil and make the pictures. But if he goes at it that way—just to do the job and get away, he won't have much success. And to think of going to make films of European scenery when he isn't really capable of it."

"Well, some of these foreigners think they know it all when they have only a smattering of it," mused Blake. "Though Alcando isn't as bad that way as lots of others. Well, we've done our best with him. And how unjust all our suspicions were—Joe's and mine. I wonder what he really did think he was up to, anyhow?"

The next day Blake and Joe were busy making many important views of the big dam, which held back the waters of the Chagres River, creating Gatun Lake. The Spaniard, too, was busy with his preparations for leaving. He was away from the boys nearly all day, coming back to the boat, which they made their headquarters, in the evening.

"Get any pictures?" asked Blake. "If you have we'll pack up your reel and send it to New York with ours. Where's the little camera and case?"

Mr. Alcando stopped short, as though struck.

"By Jove!" he cried. "I left it out at the dam. I was making some views there, and used up all the film. Then I got to working on my alarm clock, and forgot all about the camera and film case. I left them out there, and my clock, too. I'll go right back and get them!"

He turned to leave the cabin, but, as he did so, Captain Wiltsey entered. He paid no attention to the Spaniard, but, addressing Blake and Joe said:

"Boys, I have a little task for you. Have you any flash-light powder?"

"Flash-light powder? Yes, we have some," Blake said. "But we can't use it for moving pictures. It doesn't last long enough."

"Perhaps it will last long enough for what I want," the captain said.

"If you'll excuse me, I'll go back and get the camera I was so careless as to leave out," spoke Mr. Alcando.

"I'm glad he's gone," Captain Wiltsey said, as the cabin door closed. "I'd rather tell this to just you boys. I've just had a queer warning," he said.

"A warning?" repeated Joe.

"Yes, about Gatun Dam. There's a rumor that it is going to be destroyed!"



CHAPTER XXIII

THE FLASHLIGHT

For an instant the moving picture boys could hardly grasp the meaning of the fateful words spoken by Captain Wiltsey. But it needed only a look at his face to tell that he was laboring under great excitement.

"The Gatun Dam to be destroyed," repeated Joe. "Then we'd better get—"

"Do you mean by an earthquake?" asked Blake, breaking in on his chum's words.

"No, I don't take any stock in their earthquake theories," the captain answered. "That's all bosh! It's dynamite."

"Dynamite!" cried Joe and Blake in a breath.

"Yes, there are rumors, so persistent that they cannot be denied, to the effect that the dam is to be blown up some night."

"Blown up!" cried Blake and Joe again.

"That's the rumor," continued Captain Wiltsey. "I don't wonder you are astonished. I was myself when I heard it. But I've come to get you boys to help us out."

"How can we help?" asked Blake. "Not that we won't do all we can," he added hastily, "but I should think you'd need Secret Service men, detectives, and all that sort of help."

"We'll have enough of that help," went on the tug boat commander, who was also an employee of the commission that built the Canal. "But we need the peculiar help you boys can give us with your cameras."

"You mean to take moving pictures of the blowing up of the dam?" asked Joe.

"Well, there won't be any blowing up, if we can help it," spoke the captain, grimly. "But we want to photograph the attempt if it goes that far. Have you any flashlight powder?"

"Yes," Blake answered. "Or, if not, we can make some with materials we can easily get. But you can't make more than a picture or two by flashlight."

"Couldn't you if you had a very big flashlight that would last for several minutes?"

"Yes, I suppose so."

"Well, then, figure on that."

"But I don't understand it all," objected Blake, and Joe, too, looked his wonder. Both were seeking a reason why the captain had said he was glad Mr. Alcando had gone out to get the camera he had forgotten.

"I'll explain," said Mr. Wiltsey. "You have no doubt heard, as we all have down here, the stories of fear of an earthquake shock. As I said, I think they're all bosh. But of late there have been persistent rumors that a more serious menace is at hand. And that is dynamite.

"In fact the rumors have gotten down to a definite date, and it is said to-night is the time picked out for the destruction of the dam. The water of the Chagres River is exceptionally high, owing to the rains, and if a breach were blown in the dam now it would mean the letting loose of a destructive flood."

"But who would want to blow up the dam?" asked Blake.

"Enemies of the United States," was the captain's answer. "I don't know who they are, nor why they should be our enemies, but you know several nations are jealous of Uncle Sam, that he possesses such a vitally strategic waterway as the Panama Canal.

"But we don't need to discuss all that now. The point is that we are going to try to prevent this thing and we want you boys to help."

"With a flashlight?" asked Blake, wondering whether the captain depended on scaring those who would dare to plant a charge of dynamite near the great dam.

"With a flashlight, or, rather, with a series of them, and your moving picture cameras," the captain went on. "We want you boys to get photographic views of those who will try to destroy the dam, so that we will have indisputable evidence against them. Will you do it?"

"Of course we will!" cried Blake. "Only how can it be done? We don't know where the attempt will be made, nor when, and flashlight powder doesn't burn very long, you know."

"Yes, I know all that," the captain answered. "And we have made a plan. We have a pretty good idea where the attempt will be made—near the spillway, and as to the time, we can only guess at that.

"But it will be some time to-night, almost certainly, and we will have a sufficient guard to prevent it. Some one of this guard can give you boys warning, and you can do the rest—with your cameras."

"Yes, I suppose so," agreed Blake.

"It will be something like taking the pictures of the wild animals in the jungle," Joe said. "We did some of them by flashlight, you remember, Blake."

"Yes, so we did. And I brought the apparatus with us, though we haven't used it this trip. Now let's get down to business. But we'll need help in this, Joe. I wonder where Alcando—?"

"You don't need him," declared the captain.

"Why not?" asked Joe. "He knows enough about the cameras now, and—"

"He's a foreigner—a Spaniard," objected the captain.

"I see," spoke Blake. "You don't want it to go any farther than can be helped."

"No," agreed the captain.

"But how did you and the other officials hear all this?" Joe wanted to know.

"In a dozen different ways," was the answer. "Rumors came to us, we traced them, and got—more rumors. There has been some disaffection among the foreign laborers. Men with fancied, but not real grievances, have talked and muttered against the United States. Then, in a manner I cannot disclose, word came to us that the discontent had culminated in a well-plotted plan to destroy the dam, and to-night is the time set.

"Just who they are who will try the desperate work I do not know. I fancy no one does. But we may soon know if you boys can successfully work the cameras and flashlights."

"And we'll do our part!" exclaimed Blake. "Tell us where to set the cameras."

"We can use that automatic camera, too; can't we?" asked Joe.

"Yes, that will be the very thing!" cried Blake. They had found, when making views of wild animals in the jungle, as I have explained in the book of that title, that to be successful in some cases required them to be absent from the drinking holes, where the beasts came nightly to slake their thirst.

So they had developed a combined automatic flashlight and camera, that would, when set, take pictures of the animals as they came to the watering-place. The beasts themselves would, by breaking a thread, set the mechanism in motion.

"The flashlight powder—I wonder if we can get enough of that?" spoke Joe. "It'll take quite a lot."

"We must get it—somehow," declared the captain. "I fancy we have some on hand, and perhaps you can make more. There is quite a chemical laboratory here at the dam. But we've got to hustle. The attempt is to be made some time after midnight."

"Hustle it is!" cried Blake. "Come on, Joe."



CHAPTER XXIV

THE TICK-TICK

"Put one camera here, Joe."

"All right, Blake. And where will you have the other?"

"Take that with you. Easy now. Don't make a noise, and don't speak above a whisper!" cautioned Blake Stewart. "You'll work one machine, and I'll attend to the other. We'll put the automatic between us and trust to luck that one of the three gets something when the flash goes off."

The two boys, with Captain Wiltsey, had made their way to a position near the spillway, below the great Gatun Dam. It was an intensely dark night, though off to the west were distant flashes of lightning now and then, telling of an approaching storm. In the darkness the boys moved cautiously about, planting their cameras and flashlight batteries to give the best results.

They had had to work quickly to get matters in shape before midnight. Fortunately they were not delayed by lack of magnesium powder, a large quantity having been found in one of the laboratories. This was quickly made up into flashlight cartridges, to be exploded at once, or in a series, by means of a high voltage storage battery.

The moving picture cameras had been put in place, Blake to work one and Joe the other, while the automatic, which was operated by clockwork, once the trigger-string was broken, also setting off the continuous flashlight, was set between the two boys, to command a good view of the dam, and of whoever should approach to blow it up.

It now lacked an hour of midnight when, so the rumors said, the attempt was to be made. Of the nature of these rumors, and of how much truth there was in them, the boys could only guess. They did not ask too much, knowing that there might be Government secrets it would not be wise for them to know.

But that certain level-headed men did "take stock" in those rumors was evident, for elaborate preparations had been made to protect the dam. The preparations were conducted with as much secrecy as possible in order that the conspirators might not become aware of them.

"We don't want to scare them off," explained Captain Wiltsey. "That may seem a strange thing to say," he went on, "but it is the truth. Of course we don't want the dam blown up, or even slightly damaged, but it will be better to let them make the attempt, and catch them red-handed, than just to scare them off before they make a try. Because, if we do that they may only come back again, later, when we're not ready for them. But if we let them see we are prepared and can catch some of them at work, it will end the conspiracy."

"That's right!" agreed Blake. "Well, we'll do all we can to help make the capture. We'll capture their likenesses on the films, anyhow, and you'll know who they are."

"Which will be something," the captain said. "We haven't been able as yet to discover the identity of any of them. They have kept very secret, and worked very much in the dark."

It had been arranged, among Captain Wiltsey and his helpers, that they were to give a certain signal when they discovered the dynamiters at work, and then the boys would set off their flashlights and begin to work their hand cameras. The automatic one, of course, would need no attention, provided the miscreants went near enough the net-work of strings to break one and so set the mechanism in motion. But that was problematical, and, as Joe said, they would have to "trust to luck."

And so the preparations for receiving the midnight callers went on. Joe and Blake worked in silence, making ready for their part in it. All about the boys, though they could neither see nor hear them, were Uncle Sam's men—soldiers, some of them—stationed near where, so rumor said, the attempt was to be made to explode the dynamite.

"We really ought to have another helper," said Blake, thoughtfully. "There is one place we can't get in focus no matter how we try, with the three machines we have. If we had another automatic it would be all right, but we have only the one. Another hand camera would do, but we'd have to get someone to work it. I would suggest we get Mr. Alcando, but you don't seem to want him. He could easily take charge of one."

"It is better to have no foreigners," replied the captain. "Not that Mr. Alcando might not be all right, for he seems a nice chap. But he is a Spaniard, or, rather a South American, and some of the South Americans haven't any too much love for us; especially since the Canal was built."

"Why?" asked Blake.

"Oh, for various reasons. Some of them have lost trade because it shortens routes. But there, I must go and see if all the men are in place." Captain Wiltsey left him, and once more the moving picture boy resumed his vigil. All about him was silence and darkness. As well as he could he looked to see that his camera was pointing in the right direction, and that it set firmly on the tripod, the legs of which were driven into the ground.

"I'll just step over and see how Joe is," thought Blake. He judged it lacked half an hour yet of midnight.

He found Joe busy mending a broken wire that ran from the battery to the flashlight powder chamber.

"Just discovered it," Joe whispered. "Lucky I did, too, or it would have failed me just when I needed it."

"Is it fixed?" asked Blake, as his chum straightened up in the darkness.

"Yes, it'll do for a while, though it's only twisted together. Say, but isn't it dark?"

"It sure is," agreed Blake.

Together they stood there near the great dam. There came to their ears the splashing of water over the spillway, for the lake was high, and much was running to waste.

"Well, I guess I'll be getting back," said Blake in a low voice. "No telling when things will happen now."

As he started to go away Joe remarked:

"Where are you wearing your watch? I can hear it over here."

"Watch! I haven't mine on," Blake answered. "You can't see it in the dark, so I left it on the boat."

"Well, something is ticking pretty loud, and it isn't mine," Joe said, "for I did the same as you, and left it in my cabin. But don't you hear that noise?"

They both listened. Clearly to them, through the silence of the night, came a steady and monotonous tick—tick-tick—

"It's the clockwork of the automatic camera," Blake whispered.

"It can't be," answered Joe. "That's too far off. Besides, it's a different sound."

They both listened intently.

"Tick! Tick! Tick!" came to them through the dark silence.



CHAPTER XXV

MR. ALCANDO DISAPPEARS

For several seconds Blake and Joe stood there—without moving—only listening. And that strange noise they heard kept up its monotonous note.

"Hear it!" whispered Joe.

"Yes," answered Blake. "The brass box—the box—he had!"

"Yes," whispered Joe. All the suspicions he had had—all those he had laughed at Blake for harboring, came back to him in a rush. The brass-bound box contained clockwork. Was it an alarm after all? Certainly it had given an alarm now—a most portentous alarm!

"We've got to find it!" said Blake.

"Sure," Joe assented. "It may go off any minute now. We've got to find it. Seems to be near here."

They began looking about on the ground, as though they could see anything in that blackness. But they were trying to trace it by the sound of the ticks. And it is no easy matter, if you have ever tried to locate the clock in a dark room.

"We ought to give the alarm," said Blake.

"Before it is too late," assented Joe. "Where can it be? It seems near here, and yet we can't locate it."

"Get down on your hands and knees and crawl around," advised Blake. In this fashion they searched for the elusive tick-tick. They could hear it, now plainly, and now faintly, but they never lost it altogether. And each of them recognized the peculiar clicking sound as the same they had heard coming from the brass-bound box Mr. Alcando had said was his new alarm clock.

"Hark!" suddenly exclaimed Blake.

Off to the left, where was planted the automatic camera, came a faint noise. It sounded like a suppressed exclamation. Then came an echo as if someone had fallen heavily.

An instant later the whole scene was lit up by a brilliant flash—a flash that rivaled the sun in brightness, and made Blake and Joe stare like owls thrust suddenly into the glare of day.

"The dynamite!" gasped Joe, unconsciously holding himself in readiness for a shock.

"The flashlight—the automatic camera!" cried Blake. There was no need for silence now.

The whole scene was brilliantly lighted, and remained so for many seconds. And in the glare of the magnesium powder the moving picture boys saw a curious sight.

Advancing toward the dam was a solitary figure, which had come to halt when the camera went off with the flashlight. It was the figure of a man who had evidently just arisen after a fall.

"Mr. Alcando!" gasped Joe.

"The Spaniard!" fairly shouted Blake.

Then, as the two chums looked on the brilliantly lighted scene, knowing that the camera was faithfully taking pictures of every move of their recent pupil, the boys saw, rushing toward Alcando, a number of the men and soldiers who had been in hiding.

"He's surrounded—as good as caught," Blake cried. "So he's the guilty one."

"Unless there's a mistake," spoke Joe.

"Mistake! Never!" shouted his chum. "Look—the brass box!"

The glare of the distant flashlight illuminated the ground at their feet, and there, directly in front of them, was the ticking box. From it trailed two wires, and, as Blake looked at them he gave a start.

The next moment he had knelt down, and with a pair of pliers he carried for adjusting the mechanism of his camera severed the wires with a quick snap. The ticking in the box still went on, but the affair was harmless now. It could not make the electrical current to discharge the deadly dynamite.

"Boys! Boys! Where are you?" cried Captain Wiltsey.

"Here!" cried Blake. "We've stopped the infernal machine!"

"And we've got the dynamiter. He's your friend—"

The rest of the words died away as the light burned itself out. Intense blackness succeeded.

"Come on!" cried Joe. "They've got him. We won't have to work the hand cameras. The automatic did it!"

They stumbled on through the darkness. Lanterns were brought and they saw Mr. Alcando a prisoner in the midst of the Canal guards. The Spaniard looked at the boys, and smiled sadly.

"Well, it—it's all over," he said. "But it isn't as bad as it seems."

"It's bad enough, as you'll find," said Captain Wiltsey grimly. "Are you sure the wires are disconnected, boys?" he asked.

"Sure," replied Blake, holding out the brass box.

"Oh, so you found it," said the Spaniard. "Well, even if it had gone off there wouldn't have been much of an explosion."

"It's easy enough to say that—now," declared the captain.

But later, when they followed up the wires which Blake had severed, which had run from the brass-bound box to a point near the spillway of the dam, it was found that only a small charge of dynamite had been buried there—a charge so small that it could not possibly have done more than very slight damage to the structure.

"I can't understand it," said Captain Wiltsey. "They could just as well have put a ton there, and blown the place to atoms, and yet they didn't use enough to blow a boulder to bits. I don't understand it."

"But why should Mr. Alcando try to blow up the dam at all?" asked Blake, "That's what I can't understand."

But a little later they did, for the Spaniard confessed. He had to admit his part in the plot, for the moving pictures, made by the automatic camera, were proof positive that he was the guilty one.

"Yes, it was I who tried to blow up the dam," Alcando admitted, "but, as you have seen, it was only to be an attempt to damage it. It was never intended to really destroy it. It was an apparent attempt, only."

"But what for?" he was asked.

"To cause a lack of confidence in the Canal," was the unexpected answer. "Those I represent would like to see it unused. It is going to ruin our railroad interests."

Then he told of the plot in detail.

Alcando was connected, as I have told you, with a Brazilian railroad. The road depended for its profits on carrying goods across South America. Once the Canal was established goods could be transported much more cheaply and quickly by the water route. The railroad owners knew this and saw ruin ahead of them if the Canal were to be successful. Consequently they welcomed every delay, every accident, every slide in Culebra Cut that would put off the opening of the great waterway.

But the time finally came when it was finished, and a success. Then one of the largest stockholders of the railroad, an unprincipled man, planned a plot. At first his fellow stockholders would not agree to it, but he persuaded them, painting the ruin of their railroad, and saying only slight damage would be done to the Canal.

His plan was to make a slight explosion, or two or more of them, near Culebra Cut or at the great dam. This, he anticipated, would cause shippers to regard the Canal with fear, and refuse to send their goods through it. In that way the railroad would still hold its trade.

Alcando was picked for the work. He did not want to undertake it, but he was promised a large sum, and threats were made against him, for the originator of the plot had a certain hold over him.

"But I was to throw the blame on innocent parties if I could," the Spaniard went on, in his confession. "Also I was to select a means of causing the explosion that would not easily be detected. I selected moving pictures as the simplest means. I knew that some were to be made of the Canal for Government use, and I thought if I got in with the moving picture operators I would have a good chance, and good excuse, for approaching the dam without being suspected. After I had accomplished what I set out to do I could, I thought, let suspicion rest on the camera men.

"So I laid my plans. I learned that Mr. Hadley's firm had received the contract to make the views, and, by inquiries, through spies, I learned who their principal operators were. It was then I came to you boys," he said. "Ashamed as I am to confess it, it was my plan to have the blame fall on you."

Blake and Joe gasped.

"But when you saved my life at the broken bridge that time, of course I would not dream of such a dastardly trick," the Spaniard resumed. "I had to make other plans. I tried to get out of it altogether, but that man would not let me. So I decided to sacrifice myself. I would myself blow up the dam, or, rather, make a little explosion that would scare prospective shippers. I did not care what became of me as long as I did not implicate you. I could not do that.

"So I changed my plans. Confederates supplied the dynamite, and I got this clock-work, in the brass-bound box, to set it off by means of electrical wires. I planned to be far away when it happened, but I would have left a written confession that would have put the blame where it belonged.

"I kept the battery box connections and clockwork inside the small camera I carried. Tonight all was in readiness. The dynamite was planted, and I set the mechanism. But something went wrong with it. There was too much of a delay. I came back to change the timer. I broke the string connections you made, and—I was caught by the camera. The news had, somehow, leaked out, and I was caught. Well, perhaps it is better so," and he shrugged his shoulders with seeming indifference.

"But please believe me when I say that no harm would have come to you boys," he went on earnestly, "nor would the dam have been greatly damaged.

"It was all a terrible plot in which I became involved, not all through my own fault," went on the Spaniard, dramatically. "As soon as I met you boys, after you had saved my life, I repented of my part, but I could not withdraw. The plans of this scoundrel —yes, I must call him so, though perhaps I am as great—his plans called for finding out something about the big guns that protect the Canal. Only I was not able to do that, though he ordered me to in a letter I think you saw."

Blake nodded. He and Joe were beginning to understand many strange things.

"One of the secret agents brought me the box containing the mechanism that was to set off the dynamite," the Spaniard resumed. "You nearly caught him," he added, and Blake recalled the episode of the cigar smoke. "I had secret conferences with the men engaged with me in the plot," the conspirator confessed. "At times I talked freely about dynamiting the dam, in order to throw off the suspicions I saw you entertained regarding me. But I must explain one thing. The collision, in which the tug was sunk, had nothing to do with the plot. That was a simple accident, though I did know the captain of that unlucky steamer.

"Finally, after I had absented myself from here several times, to see that all the details of the plot were arranged, I received a letter telling me the dynamite had been placed, and that, after I had set it off, I had better flee to Europe."

Blake had accidentally seen that letter.

"I received instructions, the time we were starting off on the tug," went on Alcando, "that the original plot was to be changed, and that a big charge of dynamite was to be used instead of a small one.

"But I refused to agree to it," he declared. "I felt that, in spite of what I might do to implicate myself, you boys would be blamed, and I could not have that if the Canal were to suffer great damage. I would have done anything to protect you, after what you did in saving my worthless life," he said bitterly. "So I would not agree to all the plans of that scoundrel, though he urged me most hotly.

"But it is all over, now!" he exclaimed with a tragic gesture. "I am caught, and it serves me right. Only I can be blamed. My good friends, you will not be," and he smiled at Blake and Joe. "I am glad all the suspense is at an end. I deserve my punishment. I did not know the plot had been discovered, and that the stage was set to make so brilliant a capture of me. But I am glad you boys had the honor.

"But please believe me in one thing. I really did want to learn how to take moving pictures, though it was to be a blind as to my real purpose. And, as I say, the railroad company did not want to really destroy the dam. After we had put the Canal out of business long enough for us to have amassed a fortune we would have been content to see it operated. We simply wanted to destroy public confidence in it for a time."

"The worst kind of destruction," murmured Captain Wiltsey. "Take him away, and guard him well," he ordered the soldiers. "We will look further into this plot to-morrow."

But when to-morrow came there was no Mr. Alcando. He had managed to escape in the night from his frail prison, and whither he had gone no one knew.

But that he had spoken the truth was evident. A further investigation showed that it would have been impossible to have seriously damaged the dam by the amount of dynamite hidden. But, as Captain Wiltsey said, the destruction of public confidence would have been a serious matter.

"And so it was Alcando, all along," observed Blake, a few days later, following an unsuccessful search for the Spaniard.

"Yes, our suspicions of him were justified," remarked Blake. "It's a lucky thing for us that we did save his life, mean as he was. It wouldn't have been any joke to be suspected of trying to blow up the dam."

"No, indeed," agreed Blake. "And suspicion might easily have fallen on us. It was a clever trick. Once we had the Government permission to go all over with our cameras, and Alcando, as a pupil, could go with us, he could have done almost anything he wanted. But the plot failed."

"Lucky it did," remarked Joe. "I guess they'll get after that railroad man next."

But the stockholder who was instrumental in forming the plot, like Alcando, disappeared. That they did not suffer for their parts in the affair, as they should have, was rumored later, when both of them were seen in a European capital, well supplied with money. How they got it no one knew.

The Brazilian Railroad, however, repudiated the attempt to damage the Canal, even apparently, laying all the blame on the two men who had disappeared. But from then on more stringent regulations were adopted about admitting strangers to vital parts of the Canal.

"But we're through," commented Blake one day, when he and Joe had filmed the last views of the big waterway. "That Alcando was a 'slick' one, though."

"Indeed he was," agreed Joe. "The idea of calling that a new alarm clock!" and he looked at the brass-bound box. Inside was a most complicated electrical timing apparatus, for setting off charges of explosive. It could be adjusted to cause the detonation at any set minute, giving the plotter time to be a long way from the scene.

And, only because of a slight defect, Alcando would have been far from the scene when the little explosion occurred at Gatun Dam.

Once more the great Canal was open to traffic. The last of the slide in Culebra Cut had been taken out, and boats could pass freely.

"Let's make a trip through now, just for fun," suggested Blake to Joe one day, when they had packed up their cameras.

Permission was readily granted them to make a pleasure trip through to Panama, and it was greatly enjoyed by both of them.

"Just think!" exclaimed Blake, as they sat under an awning on the deck of their boat, and looked at the blue water, "not a thing to do."

"Until the next time," suggested Joe.

"That's right—we never do seem to be idle long," agreed Blake. "I wonder what the 'next time' will be?"

And what it was, and what adventures followed you may learn by reading the next volume of this series, to be called "The Moving Picture Boys Under the Sea; Or, The Treasure on the Lost Ship."

"Here you go, Blake!" cried Joe, a few days later. "Letter for you!"

"Thanks. Get any yourself?"

"Yes, one."

"Huh! How many do you want?" asked Blake, as he began reading his epistle. "Well, I'll soon be back," he added in a low voice, as he finished.

"Back where?" asked Joe.

"To New York."

And so, with these pleasant thoughts, we will take leave of the moving picture boys.

THE END