Waiting for the light to improve a little, the boys set up their cameras in a little grove of trees where they would be somewhat protected and began to make the pictures.

The battle was one of the worst of the war. There were many killed and wounded, and through it all—through the storm of firing—the moving picture boys took reel after reel of film.

"Some fight!" cried Blake, as a screaming shell burst over their heads, some scattering fragments falling uncomfortably close to them.

"I should say yes!" agreed Joe. "But look, here comes Drew on the run. I wonder what's happened."

They saw their friend the private rushing toward them, and waving his hands. He was shouting, but what he said they could not hear.

And then, so suddenly that it was like a burst of fire, Blake, Joe and Charles experienced a strange feeling! Some powerful odor overpowered them! Gasping and choking, they fell to the ground, dimly hearing Drew shouting:

"Gassed! Gassed! Put on your masks!"



CHAPTER XX

"GONE!"

Rolling down upon the American and French battlelines, coming out of the German trenches, where it had been generated as soon as it was noted that the wind was right, drifted a cloud of greenish yellow, choking chlorine gas.

Chlorine gas is made by the action of sulphuric acid and manganese dioxide on common salt. It has a peculiar corrosive effect on the nose, throat and lungs, and is most deadly in its effect. It is a heavy gas, and instead of rising, as does hydrogen, one of the lightest of gases, it falls to the ground, thus making it dangerously effective for the Huns. They can depend on the wind to blow it to the enemy's trenches and fill them as would a stream of water.

Knowing as he did the deadly nature of the gas from his own experience and that of his comrades, some of whom had been killed by it, Private Drew lost no time in sounding his warning to the moving picture boys. He had taken part in the raid on the Germans, had seen and engaged in some hard fighting, and had been sent to the rear with an order from his officer. And it was as he started that he saw, from one section of the Hun lines, the deadly gas rolling out.

He knew from the direction and strength of the wind just where it would reach to, and, seeing the moving picture boys in its path, he called to them.

"Put on your masks! Put on your masks!" cried the soldier. At the same time, as he ran, he loosed his from where it hung at his belt and began to don it.

The gas masks used in the trenches are simple affairs. They consist of a cloth helmet which is saturated with a chemical that neutralizes the action of the chlorine. There are two celluloid eye holes and a rubber tube, which is taken into the mouth and through which the air breathed is expelled. All air breathed, mixed as it is with the deadly chlorine, passes through the chemical-saturated cloth of the helmet and is thus rendered harmless. But it is a great strain on those who wear the masks, for nothing like the right kind of breathing can be done. In fact, a diver at the bottom of the sea has better and more pure air to breathe than a soldier in the open wearing a gas mask.

It was the first experience of Blake and his chums with the German gas, though they had heard much about it, and it needed but the first whiff to make them realize their danger.

Even as Private Drew called to them, and as they saw him running toward them and trying to adjust his own mask, they were overcome. As though shot, they fell to the ground, their eyes smarting and burning, their throats and nostrils seeming to be pinched in giant fingers, and their hearts laboring.

One moment they had been operating their cameras. The next they were bowled over.

"Put on your——" began Blake; and then he could say no more. He tried not to breathe as he fumbled at his belt to loosen his mask. He buried his nose deep in the cool earth, but such is the nature of this gas that it seeks the lowest level. There is no getting away from it save by going up.

In a smoke-filled room a fireman may find a stratum of cool, and comparatively fresh, air at the bottom near the floor. This is because cold air is heavier than the hot and smoke-filled atmosphere. But this does not hold with the German gas.

And so, before Blake could slip over his head the chemical-impregnated cloth, he lost consciousness. In another moment his two companions were also unconscious. Private Drew, struggling against the terrible pressure on his lungs, managed to get his helmet over his head, and then he gave his attention to his friends.

He knew that to save their lives he must get their helmets on; for a few breaths of the gas will not kill. But they will disable a person for some time, and a little longer breathing of it means a horrible death.

And so, working at top speed, the soldier, now himself protected from the fumes, though he had breathed more of them than he liked, labored to save his friends.

Suddenly a new terror developed, for, wearing their own helmets which made them look like horrible monsters out of a nightmare, the Germans charged against the French and Americans, whom they hoped to find disabled by the gas.

"Here they come with blood in their eyes if I could only see it!" mused Private Drew, as he finished fastening the helmet on Charles Anderson, having already thus protected Joe and Blake. All three boys were now unconscious, and what the outcome would be the soldier could only guess.

"But there won't be any guesswork if I leave 'em here for the Huns," he reasoned. "I've got to help 'em back—but how?"

The Germans, in a counter-offensive, were striving to regain some of the lost ground, and, for the moment, were driving before them the French and American forces. Back rushed the advance lines to their supporting columns, and Drew, seeing some of his own messmates, signaled to them, for he could not talk with the helmet on.

Fortunately his chums of the trenches understood, and while some of them caught up the unconscious boys and started with them to the rear, others saved the moving picture machines.

And then, just as it seemed that the Germans would overtake them and dispose of the whole party, there came a rush of helmet-protected Americans who speedily dispersed those making the counter-attack, pursuing them back to the very trenches which they had left not long before.

The fight went on in that gas-infested territory, a grim fight, desperate and bloody, but in which the Allies were at last successful, though Blake and his two chums saw nothing of it.

"They're in a bad way," the surgeon said, when he examined them soon after Drew and his friends brought them in. "I don't know whether we can save them."

But prompt action, coupled with American ingenuity and the knowledge that had been gained from the experience of French and British surgeons in treating cases of gas poisoning, eventually brought the moving picture boys back to the life they had so nearly left.

It was several days, though, before they were out of danger, and by that time the French and Americans had consolidated the gains it cost them so much to make, so that the place where the three boys had been overcome was now well within the Allied lines.

"Well, what happened to us?" asked Joe, when he and his chums were able to leave the hospital.

"You were gassed," explained Private Drew, who had had a slight attack himself. "Didn't you hear me yelling at you to put on your helmets?"

"Yes, and we started to do it," said Blake. "But that stuff works like lightning."

"Glad you found that out, anyhow," grimly observed the soldier. "The next time you hear the warning, 'Gas!' don't stop to think, just grab your helmet. And don't wait longer than to feel a funny tickling in your nose, as if you wanted to sneeze but couldn't. Most likely that'll be gas, too. Cover your head when you feel that."

"Thanks!" murmured Blake, for he and his chums understood that the soldier and his mates had saved their lives.

Now that the moving picture boys were out of danger and could take some stock of themselves and their surroundings, their first thoughts, naturally, were of their apparatus.

"Did they get our machines?" asked Joe.

"No; we saved the cameras for you," answered Drew.

"What about the boxes of exposed film—the ones the War Office is so anxious to get?" asked Blake.

"I didn't see anything of them," said the soldier. "We were too anxious to get you out of the gas and save the cameras to think of anything else. I didn't see any boxes of films, but I'll ask some of the boys who helped me."

Blake and his chums waited for this information anxiously, and when it came it was a disappointment, for no one knew anything of the valuable reels.

"Though they may be there yet," said Drew. "There was some fierce fighting around that shell crater where we carried you from, but it's within our lines now, and maybe the boxes are there yet. Better go and take a look."

This Blake, Joe and Charlie lost no time in doing. After a little search, for the character of the ground had so changed by reason of the shell fire they hardly knew it, the boys located the place where they had so nearly succumbed. They found the spot where their cameras had been set up, for they were marked by little piles of stones to steady the tripods. But there were no boxes of films.

"Gone!" exclaimed Blake disconsolately, as he looked about. "And we'll perhaps never get another chance to make such pictures again!"

"It surely is tough luck!" exclaimed Joe.

They saw a sentry on guard, for this place was far enough from the lines of both forces to obviate the use of trenches.

"What are you looking for, Buddies?" asked the soldier, who knew the moving picture boys.

"Some valuable army films," explained Blake, giving the details. "They're very rare, and we'll probably never get any others like them."

"Did you leave them here?"

"Right around here," answered Joe. "I think just near this pile of rocks," and he indicated the spot he meant.

"Say, now," exclaimed the American private, "I wouldn't be surprised but what those two fellows took 'em!"

"What two fellows?" cried Blake.

"Why, just as I was coming on duty here I saw two fellows, one dressed as a German soldier and the other in a blue uniform, walking around here. I thought they were up to no good, so I took a couple of shots at 'em. I don't believe I hit either of 'em, but I came so near that I made 'em jump. And then, just before they ran away, across No Man's Land, I saw them stoop down and pick up something that looked like boxes. I thought they might be something they had lost in the fight the other day, for the scrap went back and forth over this section. But now, come to think of it, they might have been boxes of your films."

"I believe they were!" cried Blake.

"What two fellows were they you saw?" asked Joe.

The soldier explained, giving as many details as he could remember, and Charlie cried:

"Lieutenant Secor for one—the chap in the blue. A French traitor!"

"He did have a uniform something like the French," admitted the private. "The other was a Fritz, though."

"Labenstein!" murmured Joe. "I wonder if it is possible that they are with the Hun army and have learned through spies that we are on this front. If they have, they would know at once that those were boxes of films, and that's why they stole them! Do you think it possible, Blake?"



CHAPTER XXI

ACROSS NO MAN'S LAND

Blake Stewart did not answer at once. He appeared to be considering what the soldier had told him. And then Blake looked across No Man's Land—that debatable ground between the two hostile forces—as though to pierce what lay beyond, back of the trenches which were held by the Germans, though, at this point, the enemy was not in sight.

"Could it, by any chance, have been Secor and Labenstein who got our films?" asked Joe.

"Very possible," agreed Blake. "Labenstein, of course, would be with the German forces, and since Secor is a traitor he would be there also. Of course it may not have been those fellows, but some other two men who had learned through their spies that we were here taking pictures and wanted them for their own purposes."

"The question is, can we get them back?" put in Charlie, scowling in the direction of the Germans.

"That's only one of the questions," observed Blake. "The main one is, where are the films now, and where did those fellows go with them?"

"Maybe I can help you out there," put in the soldier. "I saw those two fellows heading that way, down in that depression, and they certainly carried some sort of flat, square boxes under their arms."

"What's down in there?" asked Joe eagerly.

"Well, it was a machine-gun station, and old Fritz certainly played hob on our boys with it," answered the sentry. "But we wiped that out the other day, though I guess the dugout is there yet, or whatever is left of what they used to house their barker in. The two fellows I saw were heading for that spot."

"Is that between the lines?" asked Joe.

"Just about, yes, though there aren't any of our trenches, or theirs either, near there now. What trenches there were have been knocked into smithereens. That's No Man's Land down there. It belongs to whoever can keep it, but just now nobody seems to want it. I'm here to report if there's any movement on the part of Fritz to take up his station there again."

"As it is now, could we go down there?" asked Joe eagerly.

"Well, if you wanted to take a chance, I s'pose you could," answered the sentry slowly. "I wouldn't stop you. You don't belong to the army, anyhow, and we've been instructed that you're sort of privileged characters. All the same, it might be a bit dangerous. But don't let me stop you."

"Come on!" exclaimed Joe, starting down the slope that led across the bullet-scarred and shell-pitted ground.

"Where are you going?" asked Charles Anderson.

"Across No Man's Land," answered Joe grimly. "I'm going to see if we can get back those stolen army films. If they were ours, I wouldn't be so anxious about them. But they belong to Uncle Sam. He hired us to take them, and it was our fault they were lost."

"Not exactly our fault," put in Blake. "We couldn't help being gassed."

"No, but excuses in war don't go. We've got to get back those films!"

"That's right!" exclaimed Charlie. "I'm with you!"

"Oh, for the matter of fact, so am I," said Blake quickly. "I feel, as you do, Joe, that it's up to us to do all we can to get back those films. I'm only trying to think out the best plan for getting them."

"Go right down there and make that traitor Secor, and that submarine Dutchman, give 'em back!" cried Charlie.

"Yes, and perhaps make such a row that there'll be a general engagement," said Blake. "No; we've got to go at this a little differently from that. I'm in favor of getting the films away from those fellows, if they have them, but I think we'd better try to sneak up there first and see what the situation is. If we march down there in the open we'll probably be fired on—or gassed, and that's worse."

"Now you've said it, Buddy!" exclaimed the sentry. "I've had both happen to me, and getting shot, say in a soft place, ain't half as bad as the gas. Whew! I don't want any more! So, if I was you, I'd wait until after dark to make a trip across No Man's Land. You'll stand a better chance then of coming back alive."

"That's what I think," returned Blake, and though Joe and Charlie were eager for action, they admitted that their chum's plan was best.

"We'll have to make some preparations," Blake went on; "though I don't know that we need say anything to Captain Black about what we are going to do."

"He might stop us," said Charlie.

"Oh, no, he wouldn't do that," Joe assured their assistant.

"I'll tell you what to do," counseled the sentry: "I'm going to be on duty here until late this afternoon. I'll keep my eyes peeled for anything that may happen down there where that dugout used to be, and I'll let you know.

"Meanwhile, you can be getting ready to take a little excursion there after dark. You'd better take your gas masks with you, and also your automatics, for you may run into a party of Fritzes out to get the night air."

"That's what we'll do," decided Blake, and his chums agreed with him. And then they began to make their preparations for the perilous trip across No Man's Land that night.

They were not asked to make any pictures that day, for which they were thankful, as they still felt some of the effects of the gas, though they were rapidly improving.

Following the fight in which the boys so nearly lost their lives and in which there were severe losses on both sides, though with a net gain of territory in favor of the Allies, there was a period of comparative calm in the American ranks. The soldiers took advantage of this to rest and repair their damaged uniforms, arms and equipment. And it was on one of these days, when discipline was somewhat relaxed, that the moving picture boys made their preparations.

As they were left pretty much to themselves when they were not called on to be making pictures, it was rather easy for them, without exciting any comment, to get ready. This consisted in seeing that their automatic pistols were in good working order. They also applied for new gas masks, with a fresh impregnation of chemicals. When they received these, and with a supply of lampblack, they were ready, waiting only for the fall of darkness.

The lampblack was to be put on their hands and faces so that their whiteness would not be revealed in case the Germans played their searchlights on the ground the boys hoped to cover, or sent up star clusters to give light for raiding parties sent out to kill the French and American wounded, such being one of the pleasant ways in which Fritz makes war.

Late in the afternoon they paid a visit to their friend the sentry, asking if he had seen anything of the two men that they suspected might have the films—Secor and Labenstein.

"I wouldn't know 'em by those names even if I saw 'em," said the soldier, "and, as a matter of fact, I didn't see the same two chaps I saw before. But I have seen figures moving about down in that hollow, where we wiped out the machine gun squad, and I wouldn't be surprised but what there was something doing there."

"I only hope our films are there," said Joe.

"Don't build too much on it, Buddy," advised the sentry. "As I say, I saw some figures I took to be Germans down in that valley, but they may be getting ready for a raid on our lines, and may have nothing to do with your pictures."

"Well, we'll take a chance," decided Blake.

"That's what!" chimed in Joe.

Being accredited representatives of a certain branch of the army, though non-combatants, the boys were allowed to pass through the sentry lines, except in certain restricted places. They were given the countersign each night in case they desired to leave their quarters and go about.

But there was a risk in starting on this journey. As non-combatants, if they carried arms and went into the enemy's territory, they were not entitled to be considered prisoners of war. Of course they could fight for their lives, but not with the same status as could a uniformed soldier. As a matter of fact, they did not wear the regulation uniform, having dark suits better suited to this night excursion than the khaki.

Waiting until it was dark enough for their purpose and taking with them electric flashlights to use in case they got into a hut or some such place where they could not see to search for their films, and having blackened their hands and faces and seen that their weapons were in order, they sallied forth from the home of the humble French couple, many good wishes going with them.

It was a walk of three or four miles from the little village to the place where the sentry had said the dugout lay, and during the first part of the trip the boys talked to each other.

"Do you suppose we'll really find the films there?" ventured Joe.

"It's a slim chance, but one worth taking," said Blake. "Though I can't imagine what Secor and Labenstein, if those two fellows are really here, could want of them."

"Maybe they just picked them up on the chance that they would give away some of the American army secrets," suggested Charlie. "And they would show our boys were drilling, fighting, and all that. Of course some of the things on the films were actually seen by the Germans, but others were not; and I fancy those would be of value to Fritz. That's why they took 'em."

"They couldn't have known we were here taking views," remarked Joe.

"Oh, yes they could!" declared Blake. "Germany's spy system is the best in the world, and lots that goes on in America is known in Germany before half of our own people hear about it. But we'll have to get there before we can find out what is in that dugout, if it's there yet."

"Well, some part of it—maybe a hut or a brush heap—must be there, or the sentry wouldn't have seen men about it," observed Joe. "And now we'd better keep quiet. We're getting too close to talk much."

A little later they passed a sentry—not their friend—gave the proper password, and then stood on the edge of No Man's Land.

What would be their fate as they crossed it and ventured on the other side—the side held by the Germans?

"Come on!" whispered Blake softly, and, crouching down to avoid as much as possible being detected in the starlight, the boys went cautiously into the debatable territory.



CHAPTER XXII

CAPTURED

Not without a rather creepy feeling did the three boys start on their mission, the outcome of which could only be guessed. They were taking great risks, and they knew it. But it was not the first time. They had gone into the jungle to get films of wild beasts at the water hole. They had ventured into Earthquake Land where the forces of nature, if not of mankind, were arrayed against them. And they had dared the perils of the deep in getting pictures under the sea.

But these were as nothing compared to the mission on which they were now engaged, for, at any moment, there might go up from the German lines, not half a mile away, a string of lights that would reveal their presence to the ever-watchful snipers and sharp-shooters.

And, more than that, the whole area might suddenly be swept by a hail of bullets from a battery of machine guns. Both sides had these deadly weapons in readiness, and it was well known that Fritz was exceedingly nervous and apt, at times, to let burst a salvo of fire without any real reason.

The fluttering of some armless sleeve on the body of a dead man, the rattle of a loose strand of barbed wire, the movement of a sorely wounded soldier lying out in the open, might draw the German fire. And if the moving picture boys were caught in that they would be hard put to it to escape.

"The only thing to do, when you see a flash of fire, is to drop to the ground and lie as still as you can," Blake had said to his chums before they started out. "Duck your heads down on your arms and don't move. The lampblack will kill any glare from the lights and they may not see us. So remember, don't move if you see anything like a light. It may be a glare from a discharged rifle, or it may be a rocket or star cluster. Just lie low, that's the way!"

And so, as they crawled on, in crouching attitudes, over the desolate stretch that lay between them and the place they sought, they made no noise, and kept a sharp watch.

Blake led the way, his hand ready on his pistol, and the other two boys followed his example. Their gas masks were ready at their belts, but these were mainly an added precaution, as it was not likely, unless a general attack was contemplated, that the Germans would produce the chlorine.

Blake had gone a little way down the slope, Joe and Charlie following as closely as was safe, when the leader came to a halt. Watching his dim form, his chums did the same.

"What is it?" whispered Joe, in the softest of voices.

"A figure," answered Blake likewise. "I'm not sure whether it's a dead man or some one like us—trying to discover something. Do you see it?"

Joe looked. He saw a huddled heap which might, some day, have been a man. Now it was but a—heap. As the boys strained their eyes through the darkness they became aware that it was the body of a man—a French soldier who had fallen in the engagement of a few days before, and who had not yet been buried. There were many such—too many on both sides for the health and comfort of the living.

"Pass to one side," advised Joe. "We can't do him any good."

"Poor fellow!" murmured Charlie. "Ouch!" he suddenly exclaimed, in louder tones than any they had heretofore used.

"Quiet!" hissed Blake. "What's the matter?"

"A big rat ran right over my legs," answered Macaroni.

"Well, if he didn't bite you what are you yelling about?" demanded Joe. The trenches were full of rats—great, gray fellows—for there was much carrion food for them.

Once more, making a little detour, Blake started forward, but hardly had he again taken up his progress when there came the sound of a slight explosion over toward the German lines, and almost instantly the dreary stretch of No Man's Land was brightly illuminated.

"Down! Down!" hoarsely called Blake, and he and his chums dropped full length on the ground, never heeding puddles of water, the rats or the dead, for they became aware that more bodies were all about them.

Up from the German lines went a series of rockets and star clusters. They made the battle ground between the two forces almost as bright as day, so that should any of the unfortunate wounded men be seen to move they might be killed.

Perhaps some keen-eyed Hun, watching for just this chance, had detected a slight movement near the dead man beside whom Blake and his chums first stopped. And, knowing from a previous observation that the body was cold and stark, the sniper must have reasoned that the living had joined it.

Or perhaps the incautious exclamation made by Charlie when he felt the big rat may have been carried to the ever-listening ears. However that was, the glaring lights were set off, and at once hundreds of rifles, aimed over the tops of the German trenches, began to send a hail of lead across No Man's Land.

Fortunately the line of fire was either to one side of where the boys had fallen, or it was too high or too low. They did not stop to consider which it was, but were thankful that they felt none of the leaden missiles, though some sang uncomfortably close.

For perhaps five minutes the glaring lights illuminated the blood-stained ground, and the firing was kept up at intervals. It was replied to from the American and French lines, but with what effect could only be guessed.

And then, once more, darkness settled down, and the boys began to breathe more easily. They had had a narrow escape, and their journey was not half over, to say nothing of the return trip—if they lived to make it.

"Come on!" Blake cautiously whispered again. "And bear off to the right. The fire wasn't so heavy from there. Maybe we can find a gap to get through."

His companions followed him as he crawled along, actually crawling this time, for it was not safe to rise high enough to walk even in a stooping position. No one could tell when the glaring lights might be sent up again.

But, for a time, Fritz seemed satisfied with the demonstration he had made. Perhaps he had killed some of the wounded, for not all of them had been brought in. Perhaps he had only further mutilated bodies that had long since ceased to be capable of movement.

And so, over the dark and bloody ground, Blake and his chums made their way. In a little while they would be in comparative safety, for their friend the sentry had told them there were no regular trenches near the little hollow where once had stood a machine-gun emplacement and where the boys now hoped to find their precious war films.

But their journey was not destined to be peaceful. Once more the flaring lights went up, and again came the heavy firing. Again the boys crouched to get below the storm of bullets, and again they escaped. But a groan and a cry of anguish, from somewhere on their left, told them some poor unfortunate had been put out of his misery.

They waited a little while, and then again took up the perilous journey. Presently Blake, taking a cautious observation, announced that they were in comparative safety, and might walk upright.

"Where's the hut—or whatever it is?" asked Joe.

"Down in that little hollow, I take it," said Blake. "We can't see it until we round that little hill. Maybe we can't see it at all, for it may not be there," he added. "But we'd better go slow, for it may be there, and there may be some one in it."

"Secor and Labenstein, perhaps," murmured Charlie.

"Perhaps," agreed Blake. "If they are——"

He did not finish, but his chums knew he meant there might be a desperate fight.

A little later, having proceeded cautiously, the boys made the turn around the little hill that had hitherto hidden from view the hollow of which the American sentry had spoken, and then they saw in the light of the stars what seemed to be a tumbled-down hut. As a matter of fact, it had once been a concrete dugout, where a machine gun had been placed in order to fire at the French and American lines. But in the heavy fighting of the past few days this place had been captured by an American contingent. They had destroyed the gun and killed most of the crew, and the place had been blown up by a bomb. But the fierce waves of Germans had surged back over the place, driving out the Americans who, in turn, captured it again.

Just now the place was supposed to be deserted, being of no strategic value, and in a location that made it dangerous for either side to hold it.

"We'll take a look in there," said Blake, when they had drawn near and had discovered that the ruins of the concrete dugout had been covered with brush, to "camouflage" it from spying airmen.

They approached cautiously, and, as they did so, they became aware of a faint light coming from the ruins. So faint was it that at first it seemed no more than the reflection of the stars, but a long look showed that it was a light from within, but carefully screened.

"We've got to have a look in!" whispered Blake. "Maybe the films are there, and maybe not; but some person is."

"Probably Germans," said Joe.

"Very likely. But it may be that Frenchman. If we could only capture him!"

"I'd like a chance at him!" exclaimed Charlie.

"Hush!" cautioned Blake. The boys were now close to the hut, for that was all it was since the bombardment. They tried on three sides of the place to look in, but without success. Then, as they moved around to the side which faced the German lines, they saw a crack through which the light streamed in greater volume.

"Take a look, Blake," advised Joe.

His chum did so, and, with an exclamation of surprise and satisfaction, turned away from the slot, motioning to the others to look for themselves. And as Joe and Charlie looked they saw, seated on the ruins of a machine gun and other things that had been in the place, Secor and Labenstein. The two plotters had between them boxes which the boys had no difficulty in recognizing as their missing war films.

Joe was about to utter an exclamation of delight when Blake softly put his hand over his chum's mouth.

"Not a sound!" breathed Blake.

For a moment the boys stood looking in at the plotters and wondering how they could capture them, or at least get back the stolen films.

And then a door, or what had been a door, to the dugout swung open with a creak of its rusty hinges.

"What's that?" cried Secor, in French, starting to his feet.

"Only the wind," replied the German, in the tongue of his fellow-conspirator. "Only the wind."

"Ah! I thought maybe it was——"

"You thought perhaps it was the boys who own these films, but who will never see them again. I know not how valuable they may be—these films—but I was told to get them, and I have. Let the ones higher up decide on their value. But we must get our price for them—you and I. We must get a good price. We have run a great risk."

"Yes, a great risk," murmured the Frenchman.

Blake motioned to his chums to follow him into the dugout. They could see his gestures in the light of a lantern which formed the illumination of the ruins.

Cautiously the three went inside, the noise they made being covered by the rattling of the wind which had sprung up.

"We have them! We have them!" exulted Joe, in a whisper.

They were silently considering how best to surprise and capture the two men, who were still unaware of the presence of the boys, when a sudden noise came from outside. Blake and his chums, as well as the two men, started.

"That was not the wind!" exclaimed Secor.

"No, my friend. It was not. I think there is some one here besides ourselves. We must look. I——"

And then came a guttural command in German:

"Surrender—all of you! You are surrounded and are prisoners! Surrender!"



CHAPTER XXIII

THE AIRSHIP RAID

Surprise on the part of Blake and his chums, as well as on the part of Secor and Labenstein, was so complete that it would be hard to say who felt the sensation most. The moving picture boys, after danger and difficulties, had found the stolen army films and those they believed had taken them. They were about to make a dash and get not only the precious boxes, but also, if possible, capture the two plotters, when, like a bolt from a clear sky, they were themselves called upon to surrender.

"Come on!" yelled Charlie, as he understood the import of the summons to surrender. "We can make a fight for it!"

"Don't try it!" advised Blake. By the light of lanterns carried by the raiding party of Germans he had seen that they were numerous and well armed. It would have been the height of folly to resist, especially as the boys were non-combatants and not entitled to the honors of war.

"Hands up—and search them!" commanded the German officer of the raiding party, as he pointed to Blake and his two chums. He spoke in German and then lapsed into English, which he spoke very well, saying:

"It will be best for you Americans to give in quietly. Hands up!" And the order was stern.

The boys had no choice but to obey, and their weapons were quickly taken from them.

"I will allow you to keep your gas masks for the present," the German captain said, "as you may need them, as we ourselves may, before we get back to our lines."

"Then we are going back with you?" asked Joe.

"Of a certainty—yes! Did you think I would leave you here to go back to your own? Indeed not! Now, then, ready—march—all of you!" and he nodded at Secor and Labenstein.

Blake and his two friends noticed that no hostility seemed directed toward the two conspirators, who, however, appeared as much surprised at the advent of the raiding party as were the boys. It was evident, though, that some understanding existed between the German captain and Labenstein, for they talked in low voices while Secor stood a little apart. The gaze of the Frenchman rested on the boys in what Blake said later seemed a peculiar manner.

"Well, up to your old spying tricks, I see!" exclaimed Joe, with a sneer he could not forego. "Have you summoned any submarines lately?"

A strange look passed over the face of the Frenchman, but he did not reply. Labenstein, who had finished his talk with the German captain of the raiding squad, turned to the boys, and a tantalizing smile spread over his face as he said:

"Ah, we meet again, I see!"

"And you don't seem to have found much use for my flashlight," said Blake. "I hope it still works!"

The German muttered an exclamation of anger, and turned aside to pick up the boxes of films. This was too much for Charles Anderson, who sprang forward, crying:

"Say, those are ours, you Dutch thief! Let 'em alone! We came here to get 'em! Let 'em alone!"

The German captain gave a sharp order, and Charlie was forcibly pulled back by one of the soldiers.

"Say, but look here!" exclaimed the lanky assistant of the moving picture boys. "This isn't war. I mean we aren't fighting you Germans—though we might if we had the chance. We're just taking pictures, and these fellows have stolen our films," and he indicated Secor and Labenstein. The latter made some reply in German to the captain which the boys could not understand.

"Give us back our films and let us go!" demanded Macaroni. "We only came to get them!"

"Enough of this!" broke in the captain. "You are our prisoners, and you may be thankful you are alive," and he tapped his big automatic pistol significantly. "March!" he ordered.

Labenstein and Secor picked up the boxes of exposed film containing the army views and went out of the hut followed by some of the soldiers. Then the moving picture boys were told to follow, a guard of Germans, with ready bayonets, closing up the rear. A little later the boys, prisoners in the midst of the raiding party, were out under the silent stars. For the time peace had settled over the battlefield, extending across the trenches on both sides.

"I wonder what they are going to do with us," said Joe, in a low voice, to Blake.

"Hard to tell," was the quiet answer. "They're marching us toward their lines, though."

This was indeed true, the advance being toward a section of the field beyond the German trenches whence, not long before, had come the searchlights and the hail of shrapnel.

"Well, things didn't exactly turn out the way we expected," said Charlie. "I guess we'll have to make a re-take in getting back our films," he added, with grim humor. "How do you figure it out, Blake?"

The talk of the boys was not rebuked by their German captors, and indeed the captain seemed to be deep in some conversation with Secor and Labenstein.

"I don't know how it happened," Blake answered, "unless they saw us go into that hut and crept up on us."

"They crept up, all right," muttered Joe. "I never heard a sound until they called on us to surrender," he added.

"Maybe Secor and Labenstein saw us and never let on, and then sent a signal telling the others to come and get us," suggested Charlie.

"I hardly think that," replied Blake. "The Frenchman and his fellow German plotter seemed to be as much surprised as we were. You could see that."

"I guess you're right," admitted Joe. "But what does it all mean, anyhow?"

"Well, as nearly as I can figure it out," responded Blake, as he and his chums marched onward in the darkness, "Secor and Labenstein must have hidden the films in the hut after they stole them from the place where we went down under the gas attack. For some reason they did not at once turn them over to the German command."

"Maybe they wanted to hold them out and get the best offer they could for our property," suggested Charlie.

"Maybe," assented Blake. "Whatever their game was," and he spoke in a low tone which could not carry to the two plotters who were walking ahead with the German captain, "they went to the hut to get the films they had left there. And as luck would have it, we came on the scene at the same time."

"I wish we'd been a little ahead of time," complained Macaroni. "Then we might have gotten back with our films."

"No use crying over a broken milk bottle," remarked Joe.

"That's right," Blake said. "Anyhow, there we were and there Secor and his German friend were when the others came and——"

"Here we are now!" finished Joe grimly.

And there, indeed, they were, prisoners, with what fate in store none of them could say.

Suddenly from the darkness a sentinel challenged in German, and the captain of the little party answered, passing on with the prisoners.

A little later they turned down into a sort of trench and went along this, the boys being so placed that each walked between two Germans, who carried their guns with bayonets fixed, as though they would use them on the slightest provocation. But Blake and his chums gave none.

And then, making a sudden turn, the party came to what was evidently an outpost of importance. There were several large underground chambers, fitted up with some degree of comfort and a number of officers and soldiers about. Some were eating, some smoking, and others drinking, and still others sleeping. In one room could be seen a rough table, laden with maps and papers, and there were many electric lights, showing to what degree of perfection the German military system was carried out at this point. A portable dynamo and gasolene engine probably furnished the current.

The captives were halted, and a brief talk in German took place between the captain and the officer to whom he reported. What was said Blake and his chums could not, of course, hear, nor could they have understood had they heard.

A little later, however, they were ordered to march on, and then were shown into an underground room, none too clean and quite dark, and the door was banged shut on them. Just before this they had seen Secor and Labenstein go off in another direction, still carrying the boxes of films.

The echoes of the retreating footsteps of the men who had thrust them into their prison soon died away, and the boys were left to themselves in a veritable cell that was unpleasantly dirty and dark.

"Whew!" whistled Joe, after a moment of silence. "This time we certainly are up against it!"

Suddenly a light flashed in the darkness.

"What's that?" asked Joe sharply.

"I want to see what sort of hotel accommodations they've given us," was Blake's grim answer, as he flashed his pocket light about. The Germans had not taken those from the boys, and they were soon inspecting their prison.

It was merely a hole dug underground, earth, supported by timbers, forming the floor, ceiling and sides, while the entrance was made of a plank door, with cracks large enough to show that a passage ran outside—a passage along which men passed with a frequency which seemed to indicate that escape would be exceedingly difficult.

"Well, we've just got to make the best of it," said Blake. "I'm going to get what rest I can."

It could not be much at best, for there was no furniture in the cavelike cell. The boys curled up in corners—fortunately it was not cold—and thought over their situation. That it was very desperate they all admitted.

That night was like a bad dream to them. At times they dozed off in light slumber, but, as far as they knew, their captors did not so much as look in on them. They did not know, of course, when morning came, but they judged that the sun had risen when, after several hours of waiting, a tin can of water and some food was thrust in to them.

"And I'm hungry enough to eat even German sausage," announced Macaroni, as he inspected the food. It was coarse but satisfying, and the boys felt better when they had eaten it.

Later came a squad of Germans, one of whom spoke enough English to order Blake and his chums to follow them. They were led out of the dungeon, along a covered underground passage, and then they suddenly emerged into daylight.

"Well, it's a comfort to be able to see," remarked Joe, as he and his companions looked about.

Without a word as to where they were to be taken, the boys were marched along, and, for a moment, they feared they were to be the victims of a firing party. But a turn in the course showed them just ahead a group of buildings about which could be seen some German officers.

"Evidently we're going to be questioned by some one in authority," suggested Blake. "Well, that looks more hopeful."

They were at the very edge of an enclosure containing the official headquarters of that part of the German army, and the leader of their squad was about to reply to the challenge of the sentinel when a curious sound was borne to the ears of the boys. It was like a fast motor operating at some distance.

"What's that?" asked Charlie.

As if by a common impulse they all looked up, for the noise seemed to come from above, and they saw dotting the blue sky many small, black specks.

"Aeroplanes!" cried Blake.

The Germans had seen the objects in the air at the same time, but on them the sight produced quite a different effect from that made on the boys.

In an instant all thought of guarding Blake and his chums seemed to have been forgotten. Their escort ran to one side. The sentries on duty before the official headquarters hastened away, and some of the elaborately gold-laced officers ran within the buildings.

A moment later a number of soldiers could be observed some distance away manning a battery of guns, the muzzles of which pointed upward.

"They're going to fire at the airships!" cried Joe.

"And that means they are not German craft!" added Blake. "Boys, I guess the French and Americans are making an airship raid on Mr. Fritz this morning, and maybe it'll be a good thing for us. Let's hunt cover!"



CHAPTER XXIV

BURIED ALIVE

Even as Blake and his chums looked about for some place of refuge, the firing of the German anti-aircraft guns began. These weapons, designed especially for shooting straight up and sending shrapnel shells to a considerable height, were rapidly manned and fired by crews that seemed to be in readiness for just such danger.

The raid of the French and American airships, quickly as the defensive preparations were made, seemed to take the Germans by surprise. That is the only way the boys could account for the fact that their guarding escort deserted them. For deserted they had been, some of the Germans running back in the direction whence Blake and the others had come, while a few, under orders from one of the German officers, helped to man the guns of which several score were now shooting at the aircraft high above the Hun position.

Joe, Blake and Charlie paused a moment, before seeking some shelter, to watch the thrilling sight. On came the aeroplanes, like a flock of great birds, and they did not resemble anything else quite so much, high up as they were. They came on in regular formation, for the day of the lone attack by an aeroplane was passed, except under special circumstances.

Straight for the German camp—if camp it could be called—came the flying squadron. As yet the airships were too high to be hit by the German guns, however great their range.

But the airships came on. Their speed was not apparent at so great a height, but it must have been wonderful, for but a few minutes seemed to have elapsed from the time they were first sighted, far down on the horizon, until they were almost overhead.

"And now's the time for us to get under cover!" said Blake. "When they begin to drop bombs, there'll be something doing around here."

"Where'll we go?" asked Charlie.

"Oh, there ought to be plenty of bomb-proofs and dug-outs in this camp. The Germans must have been air-raided before, or they wouldn't have the anti guns ready. The most likely place to find the best cyclone cellars will be near the officers' headquarters, I think. Trust those fellows to have a safe place ready."

"Do you think they are making the raid to help us?" asked Joe.

"Hardly," replied Blake. "They probably don't even know that we have been captured. No, I guess this has been in preparation on our side for some time, judging by the number of craft in it. I hope they wipe out this dump!"

"But not until we get under cover!" said Joe. "Look! There goes one of our ships!"

As he spoke a white cloud seemed to burst in the vicinity of one of the aircraft. The machine, which with the others had come lower down, was seen to dip and plunge. Then, after what seemed a dizzy fall, it straightened out again and kept up with the others.

"Hit but not disabled," murmured Blake, as he and his chums paused in their race for shelter. "The Germans are getting the range, I guess."

"Why don't we drop some bombs?" cried Joe, speaking as though he and his friends were personally engaged.

"I guess they're waiting until they get in a favorable position," returned Blake. "Look out! Here comes one!"

Something black dropped from one of the airships. It fell in a long curve, landing in a spot which the boys could not see, and an instant later there was a terrific explosion.

"That hit an ammunition dump, all right!" cried Charlie. "Duck, fellows!"

"In here!" yelled Blake, for at that moment they came opposite what looked like the entrance to a tunnel. It was lighted by small electric lamps and appeared to extend some distance into the earth. No one could be seen in it or entering it as the boys made a dive for it.

And it was well that Blake, Joe and their assistant found shelter when they did, for an instant later the whole area was under bombardment by the airships. The boys, racing through the tunnel, dug underground and timbered and braced as is a mine shaft, could not see what went on, but they could hear and imagine.

By this time the American and French aeroplanes were directly over the German camp and were dropping tons of explosives. The bombs struck and burst, some of them setting off stores of ammunition and powerful powder designed for the big guns. And these explosions, combined with the firing of the weapons aimed to bring down the flying enemy, made a pandemonium which penetrated even to the tunnel along which the boys were fleeing.

"That's some fight out there!" cried Joe.

"If we could only film it!" added Charlie, his voice and that of his chum ringing hollow in the tunnel.

"We'd stand about as much chance as we did when the volcano let loose in Earthquake Land," answered Blake. "Come on, fellows! This isn't over yet."

"I only hope we don't run into a party of Huns who'll drive us out," murmured Joe.

But, so far, they had met no one, though ahead of them they could hear a sound as though others were running through the underground shaft seeking a place of safety.

"Where are we going, anyhow?" asked Charlie at length.

"Going until we stop," answered Joe.

"And that'll be soon," added Blake, "for I see the last of the lights."

The boys looked down the long passage, which was well made and was high enough to permit them to run upright. It was wide enough, also, for three to go abreast. As Blake had said, the string of incandescent lights, suspended overhead, came to an end a little farther on. They stopped under the third light from the last and looked about them.

"Isn't this as good a place as any?" asked Joe. "If we go on any farther we may get into a hole we can't get out of. I say, let's stay here. We'll be safe from the airship bombs."

"I don't know about that," said Blake. "If you'll notice, we have come along pretty much on the level. This tunnel wasn't dug in the side of a hill. It went into the ground slanting, and at such a gradual slope that the top can't be very far under the surface."

"What does that mean?" asked Charlie.

"It means that we haven't much dirt over our heads, and if a bomb were to drop directly above us we'd be in a bad way. I think we'd better keep on until we get to a deeper part of the cave, or whatever it is."

"But we'll have to go on in the dark," objected Joe. "There are only three more lights, and——"

Suddenly came a muffled explosion, and the lights went out, leaving the place in black gloom.

"Now there aren't any lights," said Charlie, when the echo of the dull roar had passed away. The tunnel had been shaken, and there was a pattering sound all about the boys, as if little particles of earth had been dislodged, but no other damage appeared to have been done.

"It is dark!" said Blake. "But come on. Use your pocket lights. No, hold on. We'll use only one at a time. No telling how long we may need them."

Bringing out his own light, he flashed it on and led the way. Above them a continuous roar could now be heard, and they guessed that the airships were attacking in force, directly over the German camp, and were being fired at from all sides.

"One bomb must have splattered Fritz's electric plant," observed Joe, as he and his chums hurried on as best they could in the somewhat dim light of the little pocket lamp Blake carried.

Hardly had he spoken when there came a tremendous explosion—one that staggered the boys and seemed to crumple up the tunnel as though it were made of paper.

They had no time to cry out. They were thrown down and felt rocks and stones falling about them, while their ears were deafened by the roaring sound.

Then came silence and darkness—a darkness that weighed heavily on them all, while Blake, who had been in the lead, tried to move his hand to flash on the electric light that had gone out or been broken. He could barely move, and as he felt dirt and rocks all about him there was borne to his senses the horrible message:

"Buried alive!"

After that thought mercifully came unconsciousness.



CHAPTER XXV

THE END OF LABENSTEIN

How long they lay entombed in the German tunnel the moving picture boys did not know. They must have been unconscious for some time.

Joe was the first to regain his senses. Telling about it later, he said he dreamed that he had been taking views in Earthquake Land and that, somehow or other, a volcano had fallen on his chest. He had difficulty in breathing, and no wonder, for as he came to his senses he found that a great rock and a pile of earth were across him.

Slowly at first, fearing to move much because he might bring down more debris on himself, Joe felt about. He found that his arms and hands were comparatively free, though partly buried in earth.

"I say!" he called, and his voice sounded strange in that dark and broken tunnel, "is any one here but me? Blake! Charlie! Are you alive?"

No one answered, and then, feeling his strength coming back, Joe ventured to move. He found that he could manage to emerge from the pile of earth and stones that had fallen on him, fortunately none over his head. When he ventured to stand upright he tried to pierce the darkness and find out what had become of his chums.

But he could see nothing until he thought of his pocket lamp and, taking it in his hand, flashed it about him. The light revealed to him the figures of Blake and Charlie, lying not far away and covered with debris as he had been.

He set the little light on a rock, leaving the switch on, and by the intense but limited glow, he set to work to free his companions. Blake's head was bleeding from the cut of a sharp rock, but he, like Joe and Charlie, had fallen in such a way, or rather, the cave-in had taken place in such a manner, that their heads and faces were comparatively free from dirt, else they would have been smothered.

Joe worked feverishly to free his chums and at length succeeded in freeing his assistant, who, of the two, was less covered by the debris. Charlie opened his eyes and looked about him, asking:

"What happened? Where am I?"

"Don't stop to ask questions now," directed Joe. "Help me with Blake. I'm afraid he's hurt!"

The two together got their chum cleared of the debris finally, and then Joe, taking a flask of cold coffee from his pocket, gave his now half-unconscious chum some to drink. This served further to rouse Blake, and it was soon found, aside from a painful cut on the head, that he was uninjured except for bruises, such as they all had.

"But what happened?" asked Charlie, as they sat down to rest on some rocks and took turns finishing Joe's limited supply of coffee.

"The tunnel caved in on us after a big explosion of some kind," Joe said. "I guess we're going to have trouble getting out, too."

"Let's have a look," suggested Blake. "We can't stay in here much longer or more of the roof and sides may cave in. Can we get out?"

"I haven't looked," answered Joe. "I wanted to get the dirt off you fellows. I'm afraid we're caught, though."

And they were. An examination, made with the pocket lights, showed them that the way back was blocked by a mass of rock and earth and that no progress ahead could be made for the same reason.

"I guess we'll have to dig our way out," said Joe.

"What with?" asked Charlie.

"Some of the broken boards that held up the tunnel," was the answer, and Joe pointed to pieces of timber that had been splintered and shattered by the cave-in.

"Yes, it's the only way out," agreed Blake, who, now that his cut had been bound up with bandages from the first-aid kits the boys carried, felt better. "We'll have to dig out." And after a short rest they began this work.

A terrible fear was upon them, a fear greater than that caused by their capture by the Germans with the possibility of being shot as spies. It was the fear of a horrible death—buried alive.

They dug as best they could for some time with the broken boards, their hands becoming cut and bruised by the rough edges. And yet, with all their efforts, they could not see that they had gained much.

They were digging back along the way they had come in, for, as Blake said, they knew how long the tunnel was in that direction, but they did not know how far it extended the other way.

"Is it of any use to continue?" asked Joe wearily, when they had been digging for what seemed several hours, though really it was not as long as that.

"Of course we've got to continue!" declared Blake, half savagely. "We can't give up now—and die!"

"We may die anyhow," said Joe.

They were resting in the darkness after strenuous digging. In the dark because, to save the battery, they had switched off the electric light by which they had been working.

Charlie turned to look back. They had been piling the earth behind them as they worked, but there was not much of it as yet. They had made but small impression on the debris that hemmed them in. And as Charlie looked he uttered a cry.

"What is it?" asked Blake.

"A light! Don't you see a light there?" Charlie demanded. "See! Back there through the chinks in the rock. See, a flickering light!"

There was no doubt of it! There was a gleam of light, and it appeared to come from a point where some fallen rocks were loosely piled.

Dropping their boards, which they had been using for shovels, the boys climbed as near as they could to the hole. In the dark as they were, the light showed plainly.

"Can you see anything?" asked Charlie of Joe, who was nearest.

"No, only some figures moving about. It seems like some sort of dugout beyond there, and it hasn't caved in. Maybe it's the end of the tunnel."

"Did you say you can see somebody in there?" asked Blake.

"Yes; figures moving about."

"Call to them."

"Maybe they're Germans!" exclaimed Charlie.

"They probably are," Blake answered. "But we've got to be rescued from here and take our chance with them. It's better than being buried alive. Hello, there!" he shouted. "Help us get out!" and he began tearing at the stones with his hands.

Seeing his object, his chums helped him. And then some one on the other side of the rocky barrier also began pulling down the stones, so that in a little while, the light becoming momentarily greater, the boys saw a way of escape open to them.

But it was a strange way. For when the rocks had been pulled down sufficiently to enable them to crawl through, they emerged into a space—a small room, as it were—walled with solid logs. Logs also formed the roof. It was a room lighted by a lantern, and on a pile of bags in one corner lay a huddled figure of a man. Standing near him was another man—a man in a ragged blue uniform—and at the sight of his face Blake murmured:

"Lieutenant Secor!"

"At your service!" said the Frenchman, bowing slightly.

"No!" bitterly cried Blake. "Not at our service—you traitor!"

The Frenchman seemed to wince, but at that moment a call from the huddled man in the corner attracted his attention. He bent over him, drew back the covering and revealed in the lantern's glow the face of Labenstein.

The German raised himself on one elbow, and a wild look came over his face. His eyes gleamed brightly for a moment.

"They—they here!" he murmured. "Well, perhaps it is better so."

"How better? What does he mean?" asked Blake. "Does he think——"

"Hush!" and the Frenchman spoke softly. "This is the end—of Labenstein!" And even as he spoke the man fell back dead.

Lieutenant Secor seemed to breathe a sigh of relief, as though the death of the other had brought a great release to him.

"Now I can speak," said the officer. "Now I can explain, and perhaps you will again regard me as a friend," he said softly.

"Well," returned Blake, "you probably saved our lives by helping us get out of the tunnel. But as for being friends with——"

"Please do not say it," begged the lieutenant. "I have had to play a part. It is over now. I can again take my place with my comrades and fight openly for France. For I have learned all his secrets and whence the spy-leaks came. Now my unpleasant mission is over!"

"What—what do you mean?" asked Joe, beginning, as did his chums, to have an inkling of the truth. "Aren't you two working together against us and for Germany?"

"Never I!" cried the Frenchman. "I am a member of the French Secret Service, and for months I have consorted with that dog!" and he pointed at the dead man. "I but played a part to gain his confidence and to learn from what sources Germany was getting her secret information about our soldiers and yours. Now I know. I will explain. But come, we must get out of here."

"Can we get out?" asked Blake.

"Surely, yes. The tunnel goes from here into the German trenches, and the other end was not damaged by the explosion."

"But," exclaimed Joe, "the German trenches! We don't want to go there to be captured again."

"Have no fear," said the Frenchman, with a smile. "I should, perhaps, have said what were the German trenches. They are now held by some of your own troops—the brave Americans!"

"They are?" cried Charlie.

"That is true! You shall see!"

"Hurrah!" cried the moving picture boys, and their fears and weariness seemed to depart from them in a moment.

"The great airship raid was a success," went on the Frenchman. "Our troops and yours have made a big advance, and have captured many prisoners. They would have had Labenstein, but he is beyond prisons now. Let us go hence! Even dead I can not endure his company. I suffered much on his account."

"Well, things are happening so fast I don't know which to begin to think of first," remarked Joe. "But, on general principles, I presume it's a good thing to get out of this tunnel. Come on, boys."

"One moment," interposed the lieutenant. "Perhaps you will like to take these with you."

He stooped and lifted a pile of trench bags, and the boys saw the boxes of moving picture films.

"Ours?" cried Joe.

"None else," answered the Frenchman. "I trust you will find them all right."

"Not a seal broken!" reported Charlie, who had quickly examined the cases. "This is great!"

Together, hardly able to believe their good luck, they made their way out of the log-protected room—once a German bomb-proof dugout. As they emerged into the trenches, carrying the films, the boys saw American soldiers.

"The Stars and Stripes!" cried Charlie, as he noted the United States flag. "Now we're all right!"

"Whew! We did make some advance!" added Blake, as they saw how the battle lines of the French and Americans had been extended since they had crawled into No Man's Land the night before.

The boys learned later that the airship raid was the forerunner of a big offensive that had been carried out when they were held prisoners and in the tunnel. The Germans had been driven back with heavy loss, and one of their ammunition dumps, or storage places, had been blown up, which had caused the collapse of the tunnel.

That the moving picture boys were welcomed by the soldiers, among whom they had many friends, goes without saying. And the recovery of the films was a matter for congratulation, for they were considered very valuable to the army.

"Though it was Lieutenant Secor who really saved them for us," explained Blake, when the story of their adventure was being told.

"And I am glad the time has come when Lieutenant Secor can appear in his true light," said Captain Black. "Even I suspected him, and he lost many friends who will come back to him, now that he risked all to serve his country in a role seldom honored—that of getting secret intelligence from the enemy."

For that is what the French lieutenant had been doing. Even while he was in the United States, where the boys first met him, he had been playing that part.

"But I assure you," he said to Blake and the others, "that the destruction of your films by my auto was an accident. When I found you believed it done purposely I let it go that way, as it helped me play my part the better. Also, I had to act in a manner to make you believe I was a friend of Labenstein. But that was all a part."

And it had not been an easy part for the French officer to play. He had, in ways of his own, come to suspect Labenstein, who went under various names, sometimes that of Karl Kooder. This man, who held forged citizenship papers of the United States, was a German spy and had done much to aid the Kaiser. But he accepted Lieutenant Secor as a co-worker, on the latter's representation that he, too, was a friend of Germany, or rather, as the Frenchman made Labenstein think, was willing to become so for a sum of money. So the two seemingly worked together.

"And it was thus you knew us," said the lieutenant to the boys. "Labenstein, to use one of his names, had orders to make all the trouble he could for you when you reached France, and to prevent your getting any pictures, if possible. Of course he could not do that, but he tried, even to the extent of writing a false note in London that caused your arrest. I had, seemingly, to help him, but all the while I was endeavoring to find out where the leak was on our side that enabled him to profit. And I found out. The leak will be stopped.

"I even seemed to join Labenstein in signaling the submarine, though that night, had he really succeeded in calling her with your light, I would have killed him where he stood. However, the depth charge solved that question.

"I had to escape from the ship with him to lull his suspicions against me. Then I went into the German ranks with him, being thought a deserter! That was hard for me, but I had my duty to perform.

"The rest you know. It was by a mere chance that Labenstein, when I was with him, came upon your films after the gas attack. He thought to profit personally from selling them, which is why he did not turn them over at once to his superiors. Ever since then he has been trying to dispose of them to enrich himself. And I have been trying to find a way to get them back to you without betraying myself and my mission.

"At last chance favored me. The big air attack came just after I had secured all the information I wanted. I was about to go back to my comrades and arrange for the capture of Labenstein if I could. He still had the films and was about to sell them to another German—a traitor like himself.

"Then came the big explosion, and he was fatally hurt. We both took refuge in the tunnel, Labenstein carrying with him the films, and you came just as Labenstein died. Well, perhaps it is better so."

"Yes," agreed Blake, "I think it is."

"And we have the films back!" exulted Charlie.

"But, best of all, we know Lieutenant Secor is straight!" cried Joe. "I'd hate to think anything else of him, after he saved our lives."

"Yes," agreed Blake softly.

"And now to get back on the job!" cried Joe, after a moment of silence.

And so the moving picture boys again took up their perilous calling. They soon recovered from their slight injuries caused by the cave-in of the tunnel, and, finding their cameras where they had left them in the French house, resumed the turning of the cranks.

They filmed many stirring scenes, and the records they made now form an important part of the archives of the War Office in Washington, the films so strangely lost and recovered being considered most valuable.

Lieutenant Secor became one of the boys' firmest friends, and through his help they were enabled to obtain many rare views. And now, having seen them safely through some of their perils, we will take leave of them.

THE END



[Transcriber's note: Some of the adverts appeared at the start of the book and repeated at the end. The duplicates have been removed, and the remaining series (Motion Picture Chums) have been added here.]

THE MOVING PICTURE BOYS SERIES

By VICTOR APPLETON

12mo. BOUND IN CLOTH. ILLUSTRATED. UNIFORM STYLE OF BINDING.

Moving pictures and photo plays are famous the world over, and in this line of books the reader is given a full description of how the films are made—the scenes of little dramas, indoors and out, trick pictures to satisfy the curious, soul-stirring pictures of city affairs, life in the Wild West, among the cowboys and Indians, thrilling rescues along the seacoast, the daring of picture hunters in the jungle among savage beasts, and the great risks run in picturing conditions in a land of earthquakes. The volumes teem with adventures and will be found interesting from first chapter to last.

THE MOVING PICTURE BOYS Or Perils of a Great City Depicted.

THE MOVING PICTURE BOYS IN THE WEST Or Taking Scenes Among the Cowboys and Indians.

THE MOVING PICTURE BOYS ON THE COAST Or Showing the Perils of the Deep.

THE MOVING PICTURE BOYS IN THE JUNGLE Or Stirring Times Among the Wild Animals.

THE MOVING PICTURE BOYS IN EARTHQUAKE LAND Or Working Amid Many Perils.

THE MOVING PICTURE BOYS AND THE FLOOD Or Perilous Days on the Mississippi.

THE MOVING PICTURE BOYS AT PANAMA Or Stirring Adventures Along the Great Canal.

THE MOVING PICTURE BOYS UNDER THE SEA Or The Treasure of the Lost Ship.

THE MOTION PICTURE CHUMS SERIES

MOTION PICTURE CHUMS' FIRST VENTURE MOTION PICTURE CHUMS AT SEASIDE PARK MOTION PICTURE CHUMS ON BROADWAY MOTION PICTURE CHUMS' OUTDOOR EXHIBITION MOTION PICTURE CHUMS' NEW IDEA MOTION PICTURE CHUMS AT THE FAIR MOTION PICTURE CHUMS' WAR SPECTACLE

THE TOM SWIFT SERIES

By VICTOR APPLETON

12mo. CLOTH. UNIFORM STYLE OF BINDING. COLORED WRAPPERS.

These spirited tales convey in a realistic way the wonderful advances in land and sea locomotion. Stories like these are impressed upon the memory and their reading is productive only of good.

TOM SWIFT AND HIS MOTOR CYCLE Or Fun and Adventure on the Road

TOM SWIFT AND HIS MOTOR BOAT Or The Rivals of Lake Carlopa

TOM SWIFT AND HIS AIRSHIP Or The Stirring Cruise of the Red Cloud

TOM SWIFT AND HIS SUBMARINE BOAT Or Under the Ocean for Sunken Treasure

TOM SWIFT AND HIS ELECTRIC RUNABOUT Or The Speediest Car on the Road

TOM SWIFT AND HIS WIRELESS MESSAGE Or The Castaways of Earthquake Island

TOM SWIFT AMONG THE DIAMOND MAKERS Or The Secret of Phantom Mountain

TOM SWIFT IN THE CAVES OF ICE Or The Wreck of the Airship

TOM SWIFT AND HIS SKY RACER Or The Quickest Flight on Record

TOM SWIFT AND HIS ELECTRIC RIFLE Or Daring Adventures in Elephant Land

TOM SWIFT IN THE CITY OF GOLD Or Marvellous Adventures Underground

TOM SWIFT AND HIS AIR GLIDER Or Seeking the Platinum Treasure

TOM SWIFT IN CAPTIVITY Or A Daring Escape by Airship

TOM SWIFT AND HIS WIZARD CAMERA Or The Perils of Moving Picture Taking

TOM SWIFT AND HIS GREAT SEARCHLIGHT Or On the Border for Uncle Sam

TOM SWIFT AND HIS GIANT CANNON Or The Longest Shots on Record

TOM SWIFT AND HIS PHOTO TELEPHONE Or The Picture that Saved a Fortune

TOM SWIFT AND HIS AERIAL WARSHIP Or The Naval Terror of the Seas

TOM SWIFT AND HIS BIG TUNNEL Or The Hidden City of the Andes

GROSSET & DUNLAP, PUBLISHERS, NEW YORK

THE END