His cries brought all of the others out on the porch, and at first they could scarcely believe the good news, but soon Jack and the new arrival came in sight. As Jack had been, the two professors and the others were startled when they saw how Mark was bundled up in bandages.

"He fell down stairs," explained Jack.

"Come over here where it's light, so I can see you," suggested Professor Henderson. "Perhaps some of the bandages have slipped off since you came from the hospital. Why did you come alone? Why didn't you send us word where you were as soon as you were conscious, and we would have come for you."

"Oh, I didn't want to bother you," explained the bundled-up figure. "I managed to walk it all right."

"But your injuries may need attention," insisted Mr. Henderson. "I know something about doctoring. Come here where I can see."

"No—no—the—light hurts my eyes," was the hasty reply. "I guess I'll go to bed, so as to be all ready to start in the morning. Why don't you leave for the moon to-night, professor?"

"There are still a few little details to look after. But are you sure you are well enough to go with us? We may meet with hardships up on the moon."

"Oh, I'm all ready to go," was the answer. "I'd start to-night if I could. But now I must get to bed."

"Don't you want supper?" asked Jack.

"No, I had some just before I left the hospital."

"What hospital was it?" inquired Andy Sudds. "I was in one once, and I didn't like it. There wa'nt enough air for me."

"I forget the name of the place," came the reply. "I can't think clearly. I need sleep."

The newcomer kept in the shadows of the room, as if the light hurt his eyes, and appeared restless and ill at ease. With the hand that was not in a sling he pulled the bandages closer about his face.

"Can't you tell us more about what happened?" asked Jack, for Mark was not usually so reticent, and his chum noticed it.

"There isn't much to tell," was the response. "I went to the old house, and I was looking around when I happened to tumble down stairs. I must have been knocked unconscious, but when I came to I crawled outside. A farmer was driving past, and I asked him to take me to a hospital."

"Why didn't you come home?" asked Mr. Henderson.

"Oh, I didn't want to make any trouble and delay work on the projectile. I figured that I could be with you in a few hours, and you wouldn't worry. But they insisted that I must stay in the hospital when they got me there. Then I lost consciousness again, and couldn't manage to let you know where I was. But I'm all right now."

"Why didn't you wait for me at the barn, when I went to send the telegram, as you promised you would?" asked Jack, who felt a little hurt at his chum's neglect.

"Did I promise to wait for you at some barn?"

"Yes; don't you remember?" and Jack gazed at the bandaged figure in surprise.

"Oh, yes—I—I guess I do. But I want to go to bed now," and pulling the cloths closer about his face the injured one started from the apartment.

"Here. That's not the way up to your room. The stairs are over here," called Jack, for he saw the newcomer taking the wrong direction.

"Oh, yes. Guess my mind must be wandering," and with an uneasy laugh the injured one turned about. They heard him going up stairs, and a little later Jack followed. He found that Mark's room was not occupied.

"Hi, Mark! Where are you?" he called, in some alarm.

"Here," was the answer, and the voice came from Jack's own apartment.

"Well, you're in the wrong bunk."

"Am I? Well, I must have made another mistake. My head can't be right," and with that the other came out and hastily went into the adjoining apartment.

For a moment Jack stood in the hall. He looked at the door that had closed behind the bandaged figure.

"There's something wrong," said Jack in a low voice. "How strange Mark acts! I wonder what can be the matter?"



CHAPTER XI

READY FOR THE MOON

There were busy times for the moon-voyagers the next day. They were up early, for at the last moment many little details needed to be settled. The Cardite motor had been thoroughly repaired, for the damage caused by the unknown enemy had done no permanent harm.

When the injured one appeared the bandage on his head seemed larger than ever, and his features were almost hidden. He still wore his arm in a sling.

"Well, how do you feel?" asked Jack, looking narrowly at the figure. He could not get rid of a suspicion that something was wrong with Mark.

"Oh, I'm feeling pretty fair," was the mumbled answer. "I didn't sleep much, though."

"Well, take care of yourself," advised Jack. "We are about ready to start. We'll get off about noon, Professor Henderson says. Don't try to do anything and injure your broken arm. You certainly had a tough time of it."

"Yes, I guess I did. I can't do much to help you."

"You don't need to. We're all but finished. Just hang around and watch me work. There isn't much to do."

But though Jack gave an invitation to remain near him, the other seemed to prefer being off by himself. He wandered in and out of the projectile, now and then helping Andy or Washington to carry light objects into the Annihilator. But all the while he was careful not to disturb the bandage on his face, and several times he stopped to readjust it. Nor did he talk much, which Jack ascribed to his statement that his teeth hurt him. And when the bandaged figure did speak, it was in mumbling tones, very different from Mark's usually cheerful ones.

"Well," remarked Professor Roumann, after a final inspection of the big Cardite motor—the one that was to be depended on to carry them to the moon—"I think we are about ready to leave this earth. How about it, Professor Henderson?"

"Yes, I think so. Have you made any calculation as to speed?"

"Yes, we will not have to move nearly as fast as we did when we went to Mars. We only have to cover a quarter of a million of miles at the most, and probably less than that. The motor will send us along at the rate of about a mile a second, which is three thousand six hundred miles an hour, or eighty-six thousand four hundred miles a—day. At that rate we would be at the moon in less than three days.

"But I don't want to travel as fast as that," the German went on. "I want time to make some scientific observations on the way, and so I have reduced the speed of the Cardite motor by half, though should we need to hasten our trip we can do so."

"Then we'll be about a week on the way?" asked Jack.

"About that, yes," assented Mr. Roumann.

"And could we go farther than to the moon if we wanted to?" inquired the bandaged figure mumblingly.

"Farther? What do you mean?" asked Professor Henderson quickly.

"I mean could we go to Mars if we wanted to?"

"You don't mean to say you want to go back there, and run the chance of being attacked by the savage Martians, do you?" asked Jack.

"No, I was only asking," and the other seemed confused.

"Well, of course, we could go there, as we have plenty of supplies and enough of the Cardite," said Mr. Roumann. "But I think the moon will be the limit of our trip this time."

The work went on, the last things to be put aboard the projectile being a number of scientific instruments. The injured one wandered in and out, now being in the house and again in the big shed. He seemed restless and ill at ease, and frequently he walked to the front gate and gazed down the road.

"You seem to be looking for some one," spoke Jack. "Are you expecting your girl to come along and bid you good-by, Mark?"

"Who—me? No, I—I was just looking to see if—if it was going to rain."

"Rain? Well, rain won't make much difference to us soon. We will be outside of the earth's atmosphere in a jiffy after we have started, and then rain won't worry us. Is your stateroom all fixed up?"

"No, I didn't think of that. Guess I'd better look after it."

The two started together for the projectile. The stout one entered first, and made his way through the engine room and main cabin to the compartment off which the staterooms opened. He entered one.

"Here, that's not yours," cried Jack. "That's where Professor Henderson sleeps. Yours is next to mine."

"That's right; I forgot," mumbled the other. "I must be getting absent minded since my accident. But I'll be all right soon. I'll get my room to rights, and then probably we'll start."

"I guess so," answered Jack, but he shook his head as he gazed after his chum. "Mark has certainly changed," he murmured. "I wish he'd take those bandages off, so I could get a look at his face."

The last details were completed. The big Annihilator had been run out on trucks into the yard surrounding the shed, ready to be hurled through the air. The shop, shed and house had been locked up and given in charge of a caretaker, who would remain on guard until our friends returned.

"Are we all ready?" asked Professor Henderson, as he stood ready to close the main entrance door and seal it hermetically.

"All ready, I guess," answered Jack. The stout one had gone to his stateroom, where he could be heard moving about.

"I'm ready," announced Professor Roumann. "Say the word and I'll start the motor." He was in the engine room, looking over the machinery. At that moment there came a loud yell from the galley where Washington White was.

"Heah, heah! Come back!" cried the colored man. "My Shanghai rooster is got loose!" he yelled, and, an instant later, the fowl came sailing out of the projectile, with Washington in full chase after him.

"I'll help you catch him," volunteered Jack, springing to the cook's aid, while Professor Henderson laughed, and a bandaged figure, looking from a stateroom port, wondered at the delay in starting the projectile.



CHAPTER XII

MARK'S ESCAPE

Mark Sampson was alone in the deserted house. Bound hand and foot, stripped of his clothing, and attired in some old garments that the tramps who made a hanging-out place of the old mansion had cast aside, the unfortunate lad was stretched on a pile of bagging, his heart beating partly with fear and partly with rage over a desire to escape and punish the scoundrel responsible for his plight.

The man who had captured him, after taking away Mark's clothes, had chuckled, as though at some joke.

"You may think this is funny," spoke the lad bitterly, "but you won't be so pleased when my friends get after you."

"They'll never get after me," boasted the man. "This is a good joke. To think that I can pass myself off as you; that I can join them in the projectile, and they never will be the wiser!"

"They'll soon discover that you are disguised as me," declared Mark, "and when they do they'll have you arrested."

"Yes, but they'll not discover it until we have left the earth, and are on our way to the moon. Then it will be too late to turn back, and my object will have been accomplished. I will be with them in the Annihilator, and I'll have my revenge! The projectile is due to sail to-morrow, and I'll be on hand. I'm going to leave you now. I have left orders with a friend of mine that you are to be released to-morrow night. In the meanwhile you will have to be as comfortable as you can. I wish you no harm, but I must keep you here.

"I will feed you well before I go, and put some water where you can get it. But I must leave you tied. I'll not gag you, for, no matter how you yell, no one will hear you. I have posted a notice in front of this place that it is under the watch of the police, so no tramps will venture in, and your friends will not come back.

"Now, just make yourself comfortable here, and I'll go to the moon in your place. I think I shall enjoy the trip. As I said, you will be released to-morrow night, several hours after the projectile has left the earth."

"How do you know it is to start to-morrow morning?" asked Mark.

"Oh, I have been spying around, and I overheard the professors talking. I know a thing or two, and I'll be on hand, on time, in your place! Now, I have to leave you. I've left ten dollars to pay for your suit, which I need to disguise myself with."

Then the man was gone, and Mark was left with his bitter thoughts to keep him company. The whole daring scheme of the man had been revealed. He did look something like Mark, and, attired in the lad's clothes, and by keeping his face concealed, he might pass himself off as Jack's chum; at least, until after the projectile had started.

"And then, as he says, it will be too late to return to earth and get me," thought Mark bitterly. "Oh, why did I ever try to learn this man's secret? Who is he, anyhow? Why didn't I wait for Jack at the barn, as I promised? It's all my fault. I wonder if I can't get loose?"

Mark struggled several hours desperately and at last he felt the ropes giving slightly. He redoubled his efforts. Strand by strand the cords parted. He put all his efforts into one last attempt, and to his great joy he felt his hands separate. He was partly free!

But scarcely half his task was accomplished. He had yet to discover the secret of the hidden room—a room, as he afterward learned, which had been built during slavery days to conceal the poor black men who were escaping from the South.

"But now I have my hands to work with!" exulted Mark.

Resting a bit after his strenuous labors, he took a long drink of water and attacked the ropes on his feet. They were comparatively easy to loosen, and soon he stood up unbound.

"Now for the secret panel!" he exclaimed, for he was convinced that it was by some such means that his captor had entered and left. As has already been explained, Mark knew on which side of his prison the opening was likely to be—it would be where the warning knocks had sounded. He began a minute inspection of that wall.

But if Mark hoped to speedily discover the secret he was doomed to disappointment. He went over every inch of the surface, seemingly, and pressed on every depression or projection that met his eye, as he passed the candle flame along the wall.

Success did not reward him, and, as hour after hour passed, and the candle burned lower and lower, Mark began to despair.

"I must escape before the projectile leaves," he murmured. "It will never do to let them take that man with them under the impression that they have me. I must escape! I will!"

Once more he began the tiresome task of seeking the secret spring. The candle was spluttering in the socket now. It would burn hardly another minute. Desperately Mark sought.

At last, just as the candle gave a dying gasp and flared brightly up prior to going out, the lad saw a small screw head he had not noticed before. It was sunk deep in a board.

"I'll press that and see what happens!" he exclaimed.

With a suddenness that was startling, he found himself in total darkness. The candle had burned out, but he had his finger on the screw. He pressed it with all his force.

There was a rumbling sound in the darkness, a movement as if some heavy body had slid out of the way, and Mark felt a breath of air on his cheeks. Then he saw a dim light.

"Oh, I'm out! I'm out!" he cried joyously, breathing a prayer of thankfulness at his deliverance. "I'm free! I pushed on the right spring, and the panel slid back!"

He fairly leaped forward. The morning light was streaming in through the broken windows. He saw himself in the old hall of the mansion, at the head of the stairs, in a sort of anteroom, the mantle of which apartment had swung aside to give him egress from the secret chamber through a hole in the wall. He was free!

"But am I in time?" he cried. "It is morning—and about ten o'clock, I should judge. I've been working to get free all night. Will I be in time?"

He gave one last look behind at his prison and sprang down the rickety stairs. He had but one thought—to reach home in time to unmask the villain who was impersonating him—to be in time to make the journey to the moon.

"But it's several miles, and I can't walk very fast," murmured Mark. "I'm too stiff and weak. How can I do it?"

He thought of making his way to the nearest farm house, and asking for the loan of a horse and carriage, but he looked so much like a tramp that no farmer would lend him a horse.

"And I need to make speed," he murmured.

At that moment he heard a noise down the road. It was a steady "chug- chug," like some distant motor-boat, but there was no water near at hand.

"A motorcycle!" exclaimed Mark. "Some one is coming on a motorcycle. Oh, if I could only borrow it!"

He ran down into the road. He could see the rider now. To his joy it was Dick Johnson—the lad who had brought him the mysterious note.

"Hi Dick! Dick! hold on!" cried Mark.

The lad on the motor gave one glance at the ragged figure that had hailed him. Then he turned on more power to escape from what he thought was a savage tramp.

"Wait! Stop! I want that motorcycle!" cried Mark.

"Well, you're not going to get it!" yelled back Dick. "I'll send the police after you."

Mark couldn't understand. Then a glance down at his ragged garments showed him what was the matter.

"Wait! Hold on, Dick!" he cried, running forward. "I'm Mark Sampson! I've had a terrible time! I was captured by that mysterious man, and he's got my clothes. I must get home quick!"

Dick heard, but scarcely understood. However, he comprehended that his friend was in trouble, and he wanted to help him. He slowed up, and Mark reached him.

"Lend me your motorcycle, Dick," begged Mark. "I must get home in a hurry to unmask a scoundrel. I'll leave your machine for you at our house. I won't hurt it. I'm in a hurry! Get off!"

Somewhat dazed, Dick dismounted, and Mark climbed into the saddle. He began to pedal, and then threw in the gasolene and spark. The cycle chugged off.

"I'll leave it for you at our house," Mark called back. "I'm going on a trip to the moon, and I don't want to be late."

He was fast disappearing in a cloud of dust, while Dick, gazing after him, remarked:

"Well, I always thought those fellows were crazy to go off in projectiles and things like that, and now I'm sure of it. Going to the moon! Well, I only hope he doesn't take my motorcycle there!"

Mark sped on, turning the handle levers to get the last notch of speed out of the cycle. Would he be in time?



CHAPTER XIII

A DIREFUL THREAT

Perhaps Washington White's Shanghai rooster did not care to make the trip to the moon, or perhaps the fowl had not yet seen enough of this earth. At any rate, when he flew from the projectile, uttering loud crows, and landed some distance away, he began to run back toward the coop in the rear of the yard.

"Cotch him, cotch him!" yelled the colored man. "Dat's a valuable bird!"

"We'll get him when he goes in the coop," said Jack, who found it difficult to run and laugh at the same time.

"Shall I fire my rifle off and scare him?" asked Andy Sudds.

"No, you might kill him or scare him t' death," objected Washington.

"Come on, Mark, and help," cried Jack, looking toward the projectile, where a figure was peering from the glass-covered port of the main cabin.

But the figure, whose hand was done up in voluminous bandages, did not come out, and Jack wondered the more at what he thought was a growing strangeness on the part of his chum.

Jack, followed by Andy and Washington, raced off after the rooster, while the two professors, somewhat amused, rather chaffed at the delay. But afterward they were glad of it.

"Just my luck!" muttered the bandaged one. "This delay comes at the wrong time. Why don't they go on without that confounded rooster? If we stay here too long, that fellow Mark may get loose and spoil the whole thing, or Jenkins may go and release him before the time set. It would be just like Jenkins! I've a good notion to start the projectile myself. I know how to operate the Cardite motor. Only I suppose those two professors are on guard in the engine room. I'll have to wait until they catch that rooster, I guess, but I'd like to wring his neck!"

The chase after the fowl was kept up.

"I've got him now!" cried Jack a little later, as the fowl, evidently now much exhausted, ran into another fence corner, where Jack caught him, and shut him up in the coop in the projectile.

"Yo' suttinly am de mos' contrary-minded specimen ob de chicken fambly dat I eber seed," observed Washington, breathing heavily, for his run had winded him.

"Well, are we all ready to start now?" asked Professor Henderson. "No more live stock loose, is there, Jack?"

"I think not."

"Where's Mark? Wasn't he helping you catch the rooster?"

"No, he's inside. Shall I seal the door?"

"Yes, and I'll tell Professor Roumann that we're about to start. All ready for the moon trip!"

Jack was pulling the steel portal toward him. An eager face, peering from a port, waited anxiously for the tremor which would indicate that the projectile had left the earth. In another moment they would be off.

But what was that sound coming from down the highway. A steady chug- chug—a sort of roar, as of a battery of rapid-fire guns going off in double relays! And, mingled with the explosions, there was a voice shouting:

"Wait! Hold on! Don't go without me! I'm Mark Sampson! Don't start the projectile!"

"Somebody must be in a mighty hurry on a motorcycle," thought Jack, as he paused a moment before fastening the door. Then the shouts came to his ears.

"Mark Sampson!" he cried.

Again came the cry: "Wait! Wait! Don't go without me! You've got that mysterious man on board!"

"Mark Sampson!" murmured Jack again. "That's his voice sure enough! I wonder—can it be possible—that man—with his head all bandaged up— his queer actions—I—I——"

Words failed the youth. Throwing wide open the door, he sprang out of the projectile. A moment later there dashed into the yard, where the great projectile rested, a strange figure astride of a puffing motorcycle. The figure was torn and, ragged, and the nondescript garments were covered with dust, for Mark had had a fall. But there was no mistaking the face that peered eagerly forward.

"Jack!" cried the youth on the machine.

"Mark!" ejaculated the lad who had sprung from the projectile. "What has happened? Who is the fellow who has been masquerading as you?"

"A scoundrel and a villain! Let me get at him!" and, slamming on the brakes, as he shut off the power, Mark leaped from the motorcycle, stood it up against the projectile, and clasped his chum by the hand.

"What's the matter?" asked Professor Henderson, as he, too, ran out of the Annihilator. "What does that tramp want, Jack? Give him some money, and get back in here; we ought to have started long ago." He looked at the ragged figure.

"This isn't a tramp," cried Jack. "It's Mark!"

"Mark! I thought——"

"There have been strange doings," gasped the lad in tramp's garments. "I have just escaped from being kept a prisoner. Where is the mysterious man? Oh, I'm glad I arrived in time! Were you about to start?"

"That's what we were," replied Jack. "Oh, Mark, but I'm glad to see you again! I didn't know what to think. You acted so strange—or, rather, the fellow we thought was you had me guessing!"

"Good land a' massy!" exclaimed Washington White, as he stood in the doorway, with Andy Sudds behind him. "Am dere two Marks? What's up, anyhow?"

"Don't let that fellow get away—the fellow who passed himself off as me!" shouted Mark. "Lock him up! There's some mystery about him that must be explained. He's a dangerous man to be at large."

Professor Henderson turned back to enter the projectile. Jack advised Andy to get his gun ready, with which to threaten the scoundrel in case of necessity.

At that instant there sounded a crash of glass, and the whole front of the big observation window in the side of the Annihilator was smashed to atoms. A figure leaped—a figure which no longer had its head bandaged, and whose arm was no longer in a sling—the figure of a man— the mysterious man who had held Mark a prisoner!

"There he goes!" shouted Jack. "Catch him, somebody! Andy, where's your gun?"

"I'll have it in a jiffy!" cried the hunter, as he dashed back to get it.

But the man did not linger. Scrambling to his feet after his fall, caused by his leap from the broken window, which he had smashed with a sledge hammer as soon as he understood that his game was up, he raced out of the yard. He turned long enough to shake his fist at the group assembled around the projectile, and then leaped away, calling out some words which they could not hear.

"Let's take after him," proposed Mark.

"Come on," seconded Jack.

"No, let him go; he's a desperate man, and you came just in time to unmask him," said Professor Henderson. "He might harm you if you took after him. Let him go. He has not done much damage. We can easily replace the broken window. But I can't understand what his object was in disguising himself as Mark. He certainly looked like you, Mark, especially when he kept his face concealed. Why did he do it?"

"He wanted to go to the moon in my place," answered the former prisoner of the deserted house.

"But why?" insisted Jack.

"Because, I think, he's crazy, and he didn't really know what he did want. But he certainly had me well concealed," spoke Mark. "I'm free now, however, and as soon as I get some decent clothes on I'll go with you to the moon. I wouldn't want the moon people to see me dressed this way."

"How did it happen?" asked Jack. "Tell us all about it. My! but I certainly have been puzzled since you—or rather since the person we thought was you—came back last night all bunged up. Give us the story."

"I will; give me a chance. I guess that villain is gone for good." Andy Sudds came out with his gun, and insisted on taking a look down the road and around the premises. The man was nowhere in sight.

"Now we're in for another delay," remarked Jack ruefully, as he gazed at the smashed window. "It seems as if we'd never get started for the moon."

"Oh, yes, we will," declared Professor Henderson. "We have some extra heavy plate glass in the shop, and we can soon put in another observation window."

"Let's get right to work then," proposed Jack. "That man may come back. Did you learn who he was, Mark?"

"No, he wouldn't tell his name, and he said he was doing this to get revenge on us for some fancied wrong. I can't imagine who he is. But let's work and talk at the same time. I'll tell you all that happened to me," which he did briefly.

Mark soon got rid of the tramp clothes, and donned an extra suit which had been packed in his trunk in the projectile. Then he helped replace the broken window, which, in spite of their haste, took nearly all the rest of the day to put in place.

"Shall we wait and start to-morrow?" asked Jack, when four o'clock came. "It will soon be dark."

"Darkness will make no difference to us," announced Professor Roumann. "Our Cardite motor will soon take us out of the shadow of the earth, and we will be in perpetual sunshine until we reach the moon. As we are all ready, we might as well start now."

They all agreed with this, and, after a final inspection of the projectile, the travellers entered it, and Jack was once more about to seal the big door.

Before he could do so there came riding into the yard, on his motorcycle, which he had claimed that afternoon, Dick Johnson.

"Wait a minute," he cried. "I've got a letter for you. It's from that man!"

"What—another thing to delay us?" cried Jack, but he called to Professor Roumann not to start the motor, and ran to take from Dick the letter which the lad held out.

"That same man who gave me the one for Mark gave me this, and he paid me a half a dollar to bring it here," said the boy.

"All right," answered Jack impatiently.

He looked at the note. It was addressed to the "Moon Travellers," and, considering that he was one, the youth tore open the envelope. In the dim light of the fading day he read the bold handwriting.

"I have fixed you," the letter began. "You will never get to the moon. I shall have my revenge. You took my brother Fred Axtell to Mars and left him there. I determined to get him back, and to that end I disguised myself as one of the boys, and got aboard. When we were safely away from the earth, I would have compelled you to go to Mars and rescue my brother. But my plan has failed. I will have my revenge, though. You will never reach the moon, even if you do get started. Beware! George, the brother of Fred Axtell, will avenge his fate!"

"The brother of the crazy machinist!" gasped Jack. "Now I understand his strange actions. He's crazy, too—he wanted to go to Mars—he says we will never reach the moon! Say, look here!" cried Jack, raising his voice. "Here's bad news! That scoundrel has put some game up on us! Maybe he's tampered with the machinery! It won't be safe to start for the moon until we've looked over everything carefully! He says he's fixed us, and perhaps he has!"

From the projectile came hurrying the would-be moon travellers, a vague fear in their hearts.



CHAPTER XIV

OFF AT LAST

In the gathering twilight Professor Henderson read slowly the note Dick had brought. Then he passed it to Professor Roumann. The latter shook his shaggy gray hair, and murmured something in German.

"Where did you meet the man?" asked Jack of the young motorcyclist.

"About two miles down the road. He was walking along, sort of talking to himself, and I was afraid of him. He called to me, and offered me a half a dollar to deliver this message. I didn't want to at first, but he said if I didn't he'd hurt me, so I took it. Is it anything bad?"

"We don't know yet," replied Mark.

"No, that is the worst of it," added Professor Roumann. "He has made a threat, but we can't tell whether or not he will accomplish it. We are in the dark. He may have done some secret damage to our machinery, and it will take a careful inspection to show it."

"And will the inspection have to be made now?" asked Jack.

"I think so," answered Professor Henderson gravely. "It would not be safe to start for the moon and have a breakdown before we got there. We must wait until morning to begin our trip."

"It will be the safest," spoke the German, and the boys, in spite of the fact that they were anxious to get under way, were forced to the same conclusion.

"Then if we're going to camp here for the night," proposed old Andy, "what's the matter with me and the boys having a hunt for that man? We've put up with enough from him, and it's time he was punished. If we let him go on, he'll annoy us all the while, if not now, then after we get back from the moon. I'm for giving him a chase and having him arrested."

"He certainly deserves some punishment, if only for the way he treated Mark," was Jack's opinion, his chum having related how he was drugged and kept a prisoner in the secret room, and how he escaped in time to unmask the villain.

"Well," said Professor Henderson, after some thought, "it might not be a bad plan to see if you could get that scoundrel put in some safe place, where he could make no more trouble for us. I guess the lunatic asylum is where he belongs, though I can sympathize with him on account of his brother. But it was not our fault that the crazy machinist went with us to Mars. He was a stowaway, and went against our wishes, and when he got there he tried to injure us."

"Then may Mark, Andy and I see if we can find this man?" asked Jack.

"Yes, but be careful not to get separated; and don't run any risks," cautioned the professor. "Mr. Roumann and I, with the help of Washington, will go carefully over all the machinery, and every part of the projectile, to see if any hidden damage has been done. But don't stay out too late. You had better notify the police. They may be able to give you some aid, and I don't mind letting them know about it now, as we will soon be away from here, because, no matter if they do send detectives or constables spying about now, they can learn none of our secrets."

Waiting only to partake of a hasty meal, the two boys and the veteran hunter set out, Andy with his gun over his shoulder and his sharp eyes on the lookout for any sign of Axtell, though they hardly expected to find him in the vicinity of the projectile.

Taking the road, on which Dick Johnson said he had encountered the man, the two lads and Andy proceeded, making inquiries from time to time of persons they met. But no one had seen Axtell, and the insane man, for such he seemed to be, appeared to have dropped out of sight.

On into the village the searchers went, and there they reported matters to the chief of police, telling him only so much as was necessary to give him an understanding of the situation.

"I'll send a couple of my best constables right out on the case," said the chief. "We've just appointed two new ones, and I guess they'll be glad to arrest somebody."

"Let them look out that this fellow doesn't drug them and carry them away," cautioned Mark.

"Oh, I guess my constables can look out for theirselves," spoke the chief proudly.

Once more the trailers sallied forth to renew their search. They thought perhaps they might find their man lingering in the town, but a search through the principal streets did not disclose him, and Mark proposed that they return to their home for the night, as he was tired and weary from his experience in the deserted house.

As they were turning out of the town, their attention was attracted by a disturbance on the street just ahead of them. A woman screamed, and men's voices were heard. Then came cries of: "Police! Police!"

"Some one's in trouble!" exclaimed Jack. "Let's go see what it is."

They broke into a run, and, as they approached, they saw a crowd quickly collect. It seemed to center about a man who was being held by two others, though he struggled to get away.

"Here, what's the trouble?" the boys heard a constable ask as he shouldered his way into the throng.

"This fellow tried to snatch this lady's purse and run away with it," explained one of the men who had grabbed the scoundrel. "Stand still, you brute!" he shouted at him, "or I'll shake you to pieces! Such fellows as you ought to go to the whipping-post!"

"I'll take charge of him," announced the officer. "Who is he? Does any one know?"

"Stranger in town, I guess," volunteered the other man, who had helped capture him. "Need any help, officer?"

"No, I guess I can manage him. Come along now, and behave yourself, or I'll use my club. It hasn't been tried on any one yet."

"That's one of the new constables, I guess," said Mark, and Jack nodded.

The crowd separated to allow the officer to take out his prisoner. As the latter walked forward in the grip of the constable, he remarked in a mild voice totally at variance with his bold act:

"Why, I only wanted a little change to pay my fare to the moon. I'm going there to look for my brother."

"Crazy as a loon," said one of the men.

"Or pretending that he is," added the officer.

"Mark!" cried Jack, pointing at the prisoner, "look!"

"The man who held me captive!" gasped Mark. "And he's wearing my clothes yet! But he's in custody now, and we needn't fear any more from him."

"Unless he gets away," said Jack.

"We'll go tell the chief who he is, and he'll keep him safe," suggested Mark, and they hurried to headquarters, reaching there just before the prisoner was brought in. The boys were assured by the chief that the man, who was evidently a dangerous lunatic, would be kept where he could do no harm. He would be arraigned later on the serious charge of attempted highway robbery, as well as of being a dangerous lunatic at large. When the boys and Andy got back, they found the two professors and Washington still going over the machinery in detail.

"Find anything wrong?" asked Jack, after they had told of the arrest of Axtell.

"No, but we will have another look in the morning," said Mr. Henderson. "Then, if we find nothing out of order, I think we will take a chance and start."

A thorough inspection by all hands the next day did not disclose anything wrong, and, a test of the motors and other machinery having shown that it was in good working shape, it was decided to leave the earth.

"At last, I think, we are really going to get under way to the moon," said Jack, as he closed the big main door. This time it was not reopened. All the stores and supplies were in place. The two professors were in the engine room. Washington White was in his galley, getting ready to serve the first meal in the air. Jack and Mark were in the pilot house, ready to do whatever was necessary and anxious to feel the thrill that would tell them the projectile had left the earth.

"All ready?" asked Professor Henderson.

"All ready," replied his German assistant.

"Then here we go!" announced the aged scientist.

He pulled toward him the main starting lever of the Cardite motor, while Professor Roumann opened the valve which admitted to the plates and cylinders the mysterious force that was to send them on their way.

"Elevate the bow!" called Professor Henderson.

"Elevated it is," answered the German, as he turned a wheel which directed the negative gravity force against the surface of the ground and tilted up the nose of the Annihilator, as a skyrocket is slanted in a trough before the fuse is ignited.

"Throw over the switch," directed Mr. Henderson, and the other scientist, with a quick motion, snapped it into place, amid a shower of vicious electric sparks that hissed as when hot iron is thrust into water.

"Steer straight ahead!" called Professor Henderson to Mark and Jack, who were in the pilot house. "We'll head for the moon later."

"Straight ahead it is," answered Jack.

There was a trembling to the great projectile. Up rose her sharp- pointed bow. She swayed slightly in the air. The trembling increased. The great Cardite motor hummed and throbbed. There was a crackling as from a wireless apparatus.

Then, with a rush and a roar, the big steel car, resembling an enormous cigar, soared away from the earth, like some gigantic piece of fireworks, and shot toward the sky.

"We're off!" shouted Mark.

"For the moon!" added Jack.

And the Annihilator soared upward and onward, while those in her never dreamed of the fearful adventures that were to befall them ere they would again be headed toward the earth.



CHAPTER XV

THE SHANGHAI MAKES TROUBLE

Remaining in the engine room long enough to see that all the motors and apparatus were working smoothly, Professor Henderson made his way to the pilot house forward, where Mark and Jack were in charge of the steering gears. The projectile could be started and stopped from there, as well as from the engine room, once the motor was set going.

"Well, boys, how does it feel to be in space once more?" asked the scientist.

"Fine," answered Mark. "But while I was shut up in that old house I feared I'd never have this chance again."

"It seems like old times again, to be flying through space," remarked Jack. "My! but we aren't making half the speed of which the projectile is capable. Why, we're only going about twenty miles a second," and he spoke as if that was a mere nothing.

"Twenty miles is some speed," observed Mark.

"The earth goes around the sun at the rate of nineteen miles a second, or about seventy-five times as fast as the swiftest cannon-ball, so you see, Jack, you are 'going some,' as the boys say."

"Yes, but we went much faster when we went to Mars. Still, no matter how fast we travel, you'd never realize it inside here."

This was true. So well balanced was the projectile, and so delicately poised was the machinery, that the terrifically fast rate of travel, rivalling that of the earth, was no more noticed than we, on this globe, notice our pace of nineteen miles a second around the sun.

"Everything seems to be all right," observed Professor Henderson, as he looked out of the plate-glass window of the pilot house into a sea of rolling mist, which represented the ether, for they had soon passed through the atmosphere of the earth, which scientists estimate to be two hundred miles in thickness.

"Are we going to move any faster than this?" asked Jack, who seemed possessed of a speed mania.

"Not right away," replied Mr. Henderson. "Professor Roumann wants to thoroughly test the Cardite motor first. Then, when he finds that it works all right, we may go faster. But we will be at the moon soon enough as it is. It is time we headed more directly on our proper way, though, so I think I will ask Mr. Roumann to step here and aid me in getting the projectile on the right course. You boys had better remain also and learn how it is done. You may need to know some time."

"I'll call the professor here, if he can leave the engine room," said Mark, and he found the German bending over some complicated apparatus. The scientist announced that the machines would run themselves automatically for a while, so he accompanied the lad back to the pilot- house.

There, consulting big charts of the heavens, and by making some intricate calculations, which the boys partly understood, the German and Mr. Henderson were able to locate the exact position of the moon, though that body was not then in sight, being behind the earth.

"That ought to bring us there inside of a week," announced Mr. Henderson, as he fastened the automatic steering apparatus in place. "The projectile will now be held on a straight course, and I hope we shall not have to change it."

"Could anything cause us to swerve to one side?" asked Jack.

"Sure," replied Mark. "Don't you remember how, in the trip to Mars, we nearly collided with the comet? If we are in danger of hitting another one of those things, or even a meteor, we'll steer out of the way, won't we?"

"Of course. I forgot about that," admitted Jack.

"Yes," declared Professor Roumann, "we'll have to be on the lookout for wandering meteors or other stray heavenly bodies. But our instruments will give us timely warning of them. Now, I think we can leave the projectile to herself while I make sure that all the machinery is running smoothly. You boys may stay here if you like, though there isn't much to see."

There wasn't. It was totally unlike taking a trip on earth, where the ever-varying scenery makes a journey pleasant. There was no landscape to greet the eye now. It was even unlike a trip in a balloon, for in that sort of air-craft, at least for a time, a glimpse of the earth can be had. Now there was nothing but a white blanket of mist to be seen, which rolled this way and that. Occasionally it was dispelled, and the full, golden sunlight bathed the projectile. The earth had long since dropped out of sight, for it required only a few seconds to put the Annihilator high up in a position where even the most intrepid balloonist had never ventured.

Mark and Jack sat for a few minutes in the pilot-house, looking out into the ether. But they soon tired of seeing absolutely nothing.

"I wonder what we'll do when we get to the moon?" asked Jack of his chum.

"Why, I suppose you'll make a dive for a hatful of diamonds, won't you? That is, if you still believe that Martian newspaper account."

"I sure do."

The boys found the two professors busy adjusting some of the delicate scientific instruments with which they expected to make observations on the trip, and after they reached the moon.

"What is your opinion, Professor Roumann, of the temperature at the moon's surface?" asked Mr. Henderson.

"I am in two minds about it," was the reply. "A few years ago, I see by an astronomy, Lord Rosse inferred from his observations that the temperature rose at its maximum (or about three days after full moon) far above that of boiling water."

"Boiling water!" ejaculated Mark. "Wow! That won't be very nice. I don't want to be boiled like a lobster!"

"Wait a moment," cautioned Mr. Roumann, with a smile. "Later, Lord Rosse's own investigations, and those of Langley, threw some doubts on this. There is said to be no air blanket about the moon, as there is about the earth, so that the moon loses heat as fast as it receives it; and it now seems more probable that the temperature never rises above the freezing point of water, just as is the case on our highest mountains."

"That's better," came from Jack. "We can stand a low temperature more easily than we can to be boiled; eh, Jack?"

"Sure. But I don't want to be frozen or boiled either, if I can help it. Guess I'll wear my fur suit that we brought back from the North Pole with us."

"I agree with you, Professor Roumann, about the temperature," announced Mr. Henderson, "so we must make up our minds to shiver, rather than melt. But we are prepared for that."

"What about there being no air on the moon?" asked Jack.

"Oh, we can manufacture our own oxygen," said Mark. "We can walk around with an air tank on our shoulders, as we did when we went beneath the surface of the ocean. Now, I guess——"

"Dinner am served in de dining car!" interrupted Washington White, his black face grinning cheerfully. He used to be a waiter in a Pullman, and he was proud of it. "First call fo' dinner!" he went on. "Part ob it am boiled, part am roasted, laik I done heah yo' talkin' 'bout jest now, an' part am frozed—dat's de ice cream," he added hastily, lest there be a mistake about it.

"Well, that sounds good," observed Mark. "Come on, everybody," and he led the way to the dining cabin.

They had not been at the table more than a few minutes, and had begun on the "boiled" part of the meal, which was the soup, when from the engine room there came a curious, whining noise, as when an electric motor slows up.

"What's that?" cried Professor Henderson, jumping up from his seat in alarm.

"Something wrong in the engine room," cried Mr. Roumann.

The two scientists, followed by the boys, hurried to where the various pieces of apparatus were sending the projectile forward through space. Already there was an appreciable slackening of speed.

"The Cardite motor has stopped!" cried Mr. Roumann. "Something has happened to it!"

"Can it be the result of the damage which that lunatic did?" asked Mr. Henderson.

"Perhaps," spoke Jack. "If I had him here——"

"We are falling!" shouted Mark, looking at an indicator which marked their speed and motion.

"Can't we start some other motor?" asked Jack.

At that instant from beneath the now silent Cardite machine there came a prolonged crow.

"My Shanghai rooster!" shouted Washington. "He am in dar!"

A second later the rooster scrambled out, scratching vigorously. Grains of corn were scattered about. The motor started up again, and the projectile resumed its onward way.

"The rooster stopped it!" cried Jack. "He went under it to get some corn, and he must have deranged one of the levers. Oh, you old Shanghai, you nearly gave us all heart disease!"

And the rooster crowed louder than before, while his colored owner "shooed" him out of the engine room. The trouble was over speedily, and the Annihilator was once more speeding toward the moon.



CHAPTER XVI

"WILL IT HIT US?"

"Well, for a trouble-maker, give me a rooster every time," spoke Jack, as, after an examination of the machinery, it was found that nothing was out of order. "How do you think it happened, Professor Henderson?"

"It never could have happened except in just that way," was the reply of Mr. Roumann. "Underneath the motor, where they are supposed to be out of all reach, are several self-adjusting levers. They control the speed, and also, by being moved in a certain direction, they will shut down the apparatus. The rooster crawled beneath the machine, an act that I never figured on, for I knew it was too small for any of us to reach with our hands or arms, even had we so desired. But the Shanghai's feathers must have brushed against the levers, and that stopped the action of the Cardite motor. However, I'm glad it was no worse."

"Yes, let's finish dinner now, if everything is all right," proposed Mark.

"How did the rooster get in here?" asked Jack.

"I 'spects dat's my fault," answered Washington. "I took him out ob his coop fo' a little exercise dis mawnin', an' he run in heah."

"That explains it, I think," said Mr. Roumann. "Well, Washington, don't let it happen again. We don't want to be dashed downward through space all on account of a rooster."

"No, indeedy; I'll lock him up good an' tight arter dis," promised the colored man.

They resumed the interrupted dinner, discussing the possibility of what might have happened, and congratulating themselves that it did not take place.

"It certainly seems like old times to be eating while travelling along like a cannon-ball," remarked Jack. "I declare, it gives me an appetite!"

"You didn't need any," retorted his chum. "But say! maybe things don't taste good to me, after what I got while that fellow Axtell had me a prisoner! Jack, I'll have a little more of that cocoanut pie, if you don't mind."

Jack passed over the pastry, and Mark took a liberal piece. Then Washington brought in the ice cream, which was frozen on board by means of an ammonia gas apparatus, the invention of Professor Henderson. The novelty of dining as comfortably as at home, yet being thousands of miles above the earth, and, at the same time, speeding along like a cannon-ball, did not impress our friends as much as it had during their trip to Mars.

"Well, we're making a little better time now," observed Mark, as he and the others rose from the table and went to the engine room. "The gauge shows that we're making twenty-five miles a second."

"We will soon go much faster," announced Professor Roumann. "I have not yet had a chance to test my Cardite motor to its fullest speed, and I think I will do so. I wish to see if it will equal my Etherium machine. I'll turn on the power gradually now, and we'll see what happens."

"How fast do you think it ought to send us along?" asked Jack.

"Oh, perhaps one hundred and twenty-five miles a second. You know we went a hundred miles a second when we headed for Mars. I would not be surprised if we made even one hundred and thirty miles a second with the Cardite."

"Whew! If we ever hit anything going like that!" exclaimed old Andy Sudds.

"We'd go right through it," finished Jack fervently. The professor was soon ready for the test. Slowly he shoved over the controlling lever. The Cardite motor hummed more loudly, like some great cat purring. Louder snapped the electrical waves. The air vibrated with the enormous speed of the valve wheels, and there was a prickling sensation as the power flowed into the positive and negative plates, by which the projectile was moved through space.

"Watch the hand of the speed indicator, boys," directed Professor Roumann, "while Professor Henderson and I manipulate the motor. Call out the figures to us, for we must keep our eyes on the valves." Slowly the speed indicator hand, which was like that of an automobile speedometer, swept over the dial.

"Fifty miles a second," read off Mark. The two professors shoved the levers over still more.

"Seventy-five," called Jack.

"Give it a little more of the positive current," directed Mr. Roumann.

"Ninety miles a second," read Mark a few moments later.

"We are creeping up, but we have not yet equalled our former speed," spoke Mr. Henderson. The motor was fairly whining now, as if in protest.

"One hundred and five miles," announced Jack.

"Ha! That's some better!" ejaculated the German. "I think we shall do it." Once more he advanced the speed lever a notch.

"One hundred and thirty!" fairly shouted Mark. "We are beating all records!"

"And we will go still farther beyond them!" cried Mr. Roumann. "Watch the gauge, boys!"

To the last notch went the speed handle. There was a sharp crackling, snapping sound, as if the metal of which the motor was composed was strained to the utmost. Yet it held together.

The hand of the dial quivered. It hung on the one hundred and thirty mark for a second, as if not wanting to leave it, and then the steel pointer swept slowly on in a circle, past point after point.

"One hundred and thirty-five—one hundred and forty," whispered Jack, as if afraid to speak aloud. The two professors did not look up from the motor. They looked at the oil and lubricating cups. Already the main shaft was smoking with the heat of friction.

"Look! look!" whispered Mark hoarsely.

"One hundred and fifty-three miles a second!" exclaimed Jack. "You've done it, Professor Roumann!"

"Yes, I have," spoke the German, with a sigh of satisfaction. "That is faster than mortal man ever travelled before, and I think no one will ever equal our speed. We have broken all records—even our own. Now I will slow down, but we must do it gradually, so as not to strain the machinery."

He slipped back the speed lever, notch by notch. The hand of the dial began receding, but it still marked one hundred and twenty miles a second.

Suddenly, above the roar and hum of the motor, there sounded the voice of Andy.

"Professor!" he shouted. "We're heading right toward a big, black stone! Is that the moon?"

"The moon? No, we are not half way there," said Mr. Henderson. "Are you sure, Andy?"

"Sure? Yes! I saw it from the window in the pilot-house. We are shooting right toward it."

"Look to the motor, and I'll see what it is," directed Mr. Henderson to his friend. Followed by the boys, he hurried to the steering tower. His worst fears were confirmed.

Speeding along with a swiftness unrivalled even by some stars, the projectile was lurching toward a great, black heavenly body. "It's a meteor! An immense meteor!" cried Professor Henderson, "and it's coming right toward us."

"Will it hit us?" gasped Mark and Jack together.

"I don't know. We must try to avoid it. Boys, notify Professor Roumann at once. We are in grave danger!"



CHAPTER XVII

TURNING TURTLE

Together Mark and Jack leaped for the engine room. Their faces showed the fear they felt. Even before they reached it, they realized that, at the awful speed at which they were travelling, and the fearful velocity of the meteor, there might be a crash in mid-air which would destroy the projectile and end their lives.

"I wonder if we can steer clear of it?" gasped Jack.

"If it's possible the professor will do it," responded his chum.

The next instant they were in the engine room, where Mr. Roumann was bending over the Cardite motor.

"Shut off the power!" yelled Jack.

"We are going to hit a meteor!" gasped Mark.

The German looked up with a startled glance.

"Slow down?" he repeated. "It is impossible to slow down at once! We are going ninety miles a second!" He pointed to the speed gauge.

"Then there's going to be a fearful collision!" cried Jack, and he blurted out the fact of the nearness of the heavenly wanderer.

"So!" exclaimed Professor Roumann. "Dot is bat! ferry bat!" and he lapsed into the broken language that seldom marked his almost perfect English. Then, murmuring something in his own tongue, he leaped away from the motor, calling to the boys:

"Slow it down gradually! Keep pulling the speed lever toward you! I will set in motion the repelling apparatus and go to help Professor Henderson steer out of the way. It is our only chance!"

Mark and Jack took their places beside the Cardite motor, which was still keeping up a fearful speed, though not so fast as at first. To stop it suddenly would mean that the cessation of strain could not all be diffused at once, and serious damage might result.

The only way was to come gradually down to the former speed, and, while Mark kept his eyes on the indicator, Jack pulled the lever toward him, notch by notch.

"She's down to seventy-five miles a second," whispered Mark. They were as anxious now to reduce speed as they had been before to increase it.

Meanwhile Professor Roumann had set in motion a curious bit of apparatus, designed to repel stray meteors or detached bits of comets. As is well known, bodies floating in space, away from the attraction of gravitation, attract or repel each other as does a magnet or an electrically charged object.

Acting on this law of nature, Professor Roumann had, with the aid of Mr. Henderson, constructed a machine which, when a negative current of electricity was sent into it, would force away any object that was approaching the Annihilator. In a few moments the boys at the Cardite motor heard the hum, the throb and crackling that told them that the repelling apparatus was at work.

But would it act in time? Or would the meteor prove too powerful for it? And, if it did, would the two scientists be able to steer the swiftly moving projectile out of the way of the big, black stone, as the old hunter called it?

These were questions that showed on the faces of the two lads as they bent over the motor.

"We're only going fifty miles a second now," whispered Jack.

Mark nodded his head. "Can't you pull the lever over faster?" he asked.

"I don't dare," replied his chum. There was nothing to do but to wait and gradually slow up the projectile as much as possible. The boys could hear the professors in the pilothouse shifting gears, valves and levers to change the course of the projectile. Andy Sudds and Washington White, with fear on their faces, looked into the engine room, waiting anxiously for the outcome.

"Hab—hab we hit it yet?" asked Washington, moving his hands nervously.

"I reckon not, or we'd know it," said the hunter.

"No, not yet," answered Jack, in a low voice. "How much are we making now, Mark?"

"Only thirty a second."

"Good! She's coming down."

Hardly had he spoken than there sounded a noise like thunder, or the rushing of some mighty wind. The projectile, which was trembling throughout her length from the force of the motor, shivered as though she had plunged into the unknown depths of some mighty sea. The roaring increased. Mark and Jack looked at each other. Washington White fell upon his knees and began praying in a loud voice. Old Andy grasped his gun, as though to say that, even though on the brink of eternity, he was ready.

Then, with a scream as of some gigantic shell from a thousand-inch rifle, something passed over the Annihilator; something that shook the great projectile like a leaf in the wind. And then the scream died away, and there was silence. For a moment no one spoke, and then Jack whispered hoarsely:

"We've passed it."

"Yes," added Mark, "we're safe now."

"By golly! I knowed we would!" fairly yelled Washington, leaping to his feet. "I knowed dat no old meteor could kerflumox us! Perfesser Henderson he done jumped our boat ober it laik a hunter jumps his boss ober a fence. Golly! I'se feelin' better now!"

"How did you avoid it?" asked Mark of the professor.

"With the help of the repelling machine and by changing our course. But we did it only just in time. It was an immense meteor, much larger than at first appeared, and it was blazing hot. Had it struck us, there would have been nothing left of us or the projectile either but star dust. But we managed to pass beneath it, and now we are safe."

They congratulated each other on their lucky escape, and then busied themselves about various duties aboard the air-craft. The rest of the day was spent in making minor adjustments to some of the machines, oiling others, and in planning what they would do when they reached the moon.

In this way three days and nights passed, mainly without incident. They slept well on board the Annihilator, which was speeding so swiftly through space—slept as comfortably as they had on earth. Each hour brought them nearer the moon, and they figured on landing on the surface of that wonderful and weird body in about three days more.

It was on the morning of the fourth day when, as Mark and Jack were taking their shift in the engine room, that Jack happened to glance from the side observation window, which was near the Cardite motor. What he saw caused him to cry out in surprise.

"I say, Mark, look here! There's the moon over there. We're not heading for it at all!"

"By Jove! You're right!" agreed his chum. "We're off our course!"

"We must tell Professor Henderson!" cried Jack. "I'll do it. You stay here and watch things."

A few seconds later a very much alarmed youth was rapidly talking to the two scientists, who were in the pilot-house.

"Some unknown force must have pulled us off our course," Jack was saying. "The moon is away off to one side of us."

To his surprise, instead of being alarmed, Mr. Roumann only smiled.

"It's true," insisted Jack.

"Of course, it is," agreed Mr. Henderson. "We can see it from here, Jack," and he pointed to the observation window, from which could be noticed the moon floating in the sky at the same time the sun was shining, a phenomenon which is often visible on the earth early in the morning at certain of the moon's phases.

"Will we ever get there?" asked Jack.

"Of course," replied Mr. Roumann. "You must remember, Jack, that the moon is moving at the same time we are. Had I headed the projectile for Luna, and kept it on that course, she would, by the time we reached her, been in another part of the firmament, and we would have overshot our mark. So, instead, I aimed the Annihilator at a spot in the heavens where I calculated the moon would be when we arrived there. And, if I am not mistaken, we will reach there at the same time, and drop gently down on Luna."

"Oh, is that it?" asked the lad, much relieved.

"That's it," replied Mr. Henderson. "And that's why we seem to be headed away from the moon. Her motion will bring her into the right position for us to land on when the time comes."

"Then I'd better go tell Mark," said the lad. "He's quite worried." He soon explained matters to his chum, and together they discussed the many things necessary to keep in mind when one navigates the heavens.

That day saw several thousand more miles reeled off on the journey to the moon, and that evening (or rather what corresponded to evening, for it was perpetual daylight) they began to make their preparations for landing. Their wonderful journey through space was nearing an end.

"I guess that crazy Axtell fellow was only joking when he said we'd never reach the moon," ventured Jack. "Nothing has happened yet."

"Only the meteor," said Mark, "and he couldn't know about that. I guess he didn't get a chance to damage any of the machinery."

"No, we seem to be making good time," went on his chum. "I think I'll go and——"

Jack did not finish his sentence. Instead he stared at one of the instruments hanging from the walls of the engine room. It was a sort of barometer to tell their distance from the earth, and it swung to and fro like a pendulum. Now the instrument was swinging out away from the wall to which it was attached. Further and further over it inclined. Jack felt a curious sensation. Mark put his hand to his head.

"I feel—feel dizzy!" he exclaimed. "What is the matter?"

"Something has happened," cried Jack.

The instrument swung over still more. Some tools fell from a work bench, and landed on the steel floor with a crash. The boys were staggering about the engine room, unable to maintain their balance.

There came cries of fear from the galley, where Washington White was rattling away amid his pots and pans. Andy Sudds was calling to some one, and from the pilot-house came the excited exclamations of Professors Henderson and Roumann.

"We're turning turtle!" suddenly yelled Jack. "The projectile is turning over in the air! Something has gone wrong! Perhaps this is the revenge of that crazy man!" and, as he spoke, he fell over backward, Mark following him, while the Annihilator was turned completely over and seemed to be falling down into unfathomable depths.



CHAPTER XVIII

AT THE MOON

Confusion reigned aboard the Annihilator. It had turned completely over, and was now moving through space apparently bottom side up. Of course, being cigar shaped, this did not make any difference as far as the exterior was concerned, but it did make a great difference to those within.

The occupants of the great shell had fallen and slid down the rounded sides of the projectile, and were now standing on what had been the ceiling. Objects that were not fast had also followed them, scattering all about, some narrowly missing hitting our friends. Of course, the machinery was now in the air, over the heads of the travellers.

This was one of the most serious phases of the accident, for the great Cardite motor was built to run while in the other position, and when it was turned upside down it immediately stopped, and the projectile, deprived of its motive power, at once began falling through space.

"What has happened? What caused it?" cried Mark, as he crawled over to where Jack sat on the ceiling, with a dazed look on his face.

"I don't know. Something went wrong. Here comes Professor Henderson and Mr. Roumann. We'll ask them."

The two scientists were observed approaching from the pilot-house. They walked along what had been the ceiling, and when they came to the engine room they had to climb over the top part of the door frame.

"What's wrong?" asked Jack.

"Our center of gravity has become displaced," answered Mr. Henderson. "The gravity machine has either broken, or some one has been tampering with it. Did either of you boys touch it?"

"No, indeed!" cried Mark, and his chum echoed his words.

"I wonder if Washington could have meddled with it?" went on the scientist.

At that moment the colored cook came along, making his way cautiously into the engine room. He was an odd sight. Bits of carrots, turnips and potatoes were in his hair, while from one ear dangled a bunch of macaroni, and his clothes were dripping wet.

"My kitchen done turned upside down on me!" wailed Washington, "an' a whole kettle ob soup emptied on my head! Oh, golly! What happened?"

The aged scientist looked toward the German. The latter was gazing up at the motionless Cardite motor over his head.

"There is but one way," he answered. "We must restore our centre of gravity to where it was before. Then the projectile will right herself."

"Can it be done?" asked Mark.

"It will be quite an undertaking, but we must attempt it. Bring some tables and chairs, so I can stand up and reach the equilibrium machine."

From where they had fallen to the ceiling, which was now the floor, Jack and Mark brought tables and chairs, and made a sort of stepladder. On this Professor Roumann mounted, and at once began the readjusting of the centre of gravity.

It was hard work, for he had to labor with his arms stretched up in the air, and any one who has even put up pictures knows what that means. The muscles are unaccustomed to the strain. The German scientist, though a strong man, had to rest at frequent intervals.

"We're falling rapidly," announced Jack, in a low voice, as he looked at the height gauge.

"I am doing all I can," answered Mr. Roumann. "I think I will soon be able to right the craft."

He labored desperately, but he was at a disadvantage, for the Annihilator was not now moving smoothly through space. With the stopping of the motor she was falling like some wobbly balloon, swaying hither and thither in the ether currents.

But Professor Roumann was not one to give up easily. He kept at his task, aided occasionally by Professor Henderson and by the boys whenever they could do anything.

Finally the German cried out:

"Ah, I have discovered the trouble. It is that scoundrel Axtell! See!" And reaching into the interior of the machine he pulled out a small magnet. To it was attached a card, on which was written:

"I told you I would have my revenge!" It was signed with Axtell's name.

"This was the dastardly plot he evolved," said Professor Roumann. "He slipped this magnet into the equilibrium machine, knowing that in time it would cause a deflection of the delicate needles, and so shift the centre of gravity. He must have done this as a last resort, and to provide for his revenge in case we discovered him on board after we started. It was a cruel revenge, for had I not discovered it we would soon all be killed."

"Is the machine all right now?" asked Jack.

"It will be in a few minutes. Here, take this magnet and put it as far away from the engine room as possible."

It was the work of but a few minutes, now that the disturbing element was removed, to readjust the gravity machine, and Mr. Roumann called:

"Look out, now, everybody! We're going to turn right side up again!"

As he spoke he turned a small valve wheel. There was a clanging of heavy ballast weights, which slid down their rods to the proper places. Then, like some great fish turning over in the water, the Annihilator turned over in the ether, and was once more on her proper keel, if such a shaped craft can be said to have a keel.

Of course, the occupants of the space ship went slipping and sliding back, even as they had fallen ceilingward before, but they were prepared for it, and no one was hurt. From the galley came a chorus of cries, as pots and pans once more scattered about Washington, but there was no more soup to spill.

As soon as the Annihilator was righted, the Cardite motor began to work automatically, and once more the projectile, with the seekers of the moon, was shooting through space at their former speed. They had lost considerable distance, but it was easy to make it up.

"Well, that was an experience," remarked Jack, as he and his chum began picking up the tools and other objects that were scattered all about by the change in equilibrium.

"I should say yes," agreed Mark. "I'm glad it didn't happen at dinner time. That fellow Axtell is a fiend to think of such a thing."

"Indeed, he is! But we're all right now, though it did feel funny to be turned upside down."

An inspection of the projectile was made, but they could discover no particular damage done. She seemed to be moving along the same as before, and, except for the upsetting of things in the store-room, it would hardly have been known, an hour later, that a dreadful accident was narrowly averted.

Washington made more soup, and soon had a fine meal ready, over which the travellers discussed their recent experience.

"And when do you think we will arrive?" asked Jack of Mr. Henderson.

"We ought to be at the moon inside of two days now. We have not made quite the speed we calculated on, but that does not matter. I think we will go even more slowly on the remainder of the trip, as I wish to take some scientific observations."

"Yes, and so do I," added Mr. Roumann. "I think if we make fifteen miles a second from now on we will be moving fast enough."

Accordingly the Cardite motor was slowed down, and the projectile shot through space at slightly reduced speed, while the two scientists made several observations, and did some intricate calculating about ether pressure, the distance of heavenly bodies and other matters of interest only to themselves.

It was on the afternoon of the third day following the turning turtle of the Annihilator that Mark, who was looking through a telescope in the pilot-house, called out: "I say, Jack, look here!"

"What's the matter?" asked his chum.

"Why, we're rushing right at the moon! I can see the mountains and craters on it as plain as though we were but five miles away!"

"Then we must be nearly there," observed Jack. "Let's tell the others, Mark."

They hurried to inform the two professors, who at once left their tables of figures and entered the steering chamber. Then, after gazing through the glass, Mr. Henderson announced: "Friends, we will land on the moon in half an hour. Get ready."

"Are we really going to be walking around the moon inside of thirty minutes?" asked Mark.

"I don't know about walking around on it," answered the German. "We first have to see if there is an atmosphere there for us to breathe, and whether the temperature is such as we can stand. But the Annihilator will soon be there."

The speed of the Cardite motor was increased, and so rapidly did the projectile approach Luna that glasses were no longer needed to distinguish the surface of the moon.

There she floated in space, a great, silent ball, but not like the earth, pleasantly green, with lakes and rivers scattered about in verdant forests. No, for the moon presented a desolate surface to the gaze of the travellers. Great, rugged mountain peaks arose all about immense caverns that seemed hundreds of miles deep. The surface was cracked and seamed, as if by a moonquake. Silence and terrible loneliness seemed to confront them.

"Maybe it's better on some other part of the surface," said Jack, in a low voice.

"Perhaps," agreed Mark. "It's certainly not inviting there."

Nearer and nearer they came to the moon. It no longer looked like a great sphere, for they were so close that their vision could only take in part of the surface, and it began to flatten out, as the earth does to a balloonist.

And the nearer they came to it the more rugged, the more terrible, the more desolate did it appear. Would they be able to find a place to land, or would they go hurtling down into some awful crater, or be dashed upon the sharp peak of some mountain of the moon?

It was a momentous question, and anxious were the faces of the two professors.

"Mr. Henderson, if you will undertake to steer to some level place, I will take charge of the motor," suggested Mr. Roumann. "I will gradually reduce the speed, and get the repelling machine in readiness, so as to render our landing gentle."

"Very well," responded the aged scientist, as he grasped the steering wheel.

The progress of the Annihilator was gradually checked. More and more slowly it approached the moon. The mountains seemed even higher now, and the craters deeper.

"What a terrible place," murmured Jack. "I shouldn't want to live there."

"Me either," said Mark.

"Can you see a place to land?" called Professor Roumann through the speaking-tube from the engine room to the steering tower.

"Yes, we seem to be approaching a fairly level plateau," was Mr. Henderson's reply.

"Very well, then, I'll start the repelling machine."

The Cardite motor was stopped. The projectile was now being drawn toward the moon by the gravity force of the dead ball that once had been a world like ours. Slowly and more slowly moved the great projectile.

There was a moment of suspense. Mr. Henderson threw over the steering wheel. The Annihilator moved more slowly. Then came a gentle shock. The dishes in the galley rattled, and there was the clank of machinery. The Shanghai rooster crowed.

"We're on the moon at last!" cried jack, peering from an observation window at the rugged surface outside.

"Yes; and now to see what it's like," added Mark. "We'll go outside, and——"

"Wait," cautioned Professor Roumann. "First we must see if we can breathe on the moon, and whether the temperature will support life. I must make some tests before we venture out of the projectile."



CHAPTER XIX

TORCHES OF LIFE

The natural inclination of the boys to rush out on the surface of the moon to see what it was like was checked by the words of caution from Professor Roumann.

"Do you think it would be dangerous to venture outside the projectile?" asked Jack, as he looked from the window and noted the rugged, uneven surface of the moon.

"Very much so," was the answer. "According to most astronomers, there is absolutely no air on the moon, also no moisture, and the temperature is either very high or around the freezing point. We must find out what it is."

"How can we?" inquired Mark.

"I'll soon show you," went on the German. "Professor Henderson, will you kindly assist me."

When it had been decided to come to the moon in quest for the field of diamonds, certain changes had been made in the Annihilator to fit it for new conditions that might be met. One of these consisted of an aperture in the two sides of the projectile permitting certain delicate instruments to be thrust out, so that the conditions they indicated could be read on dials or graduated scales from within.

"We will first make a test of the temperature," said Mr. Roumann, "as that will be the easiest." Accordingly a thermometer was put outside, and those in the air-craft anxiously watched the red column of spirits. The temperature was marked as seventy-five inside the Annihilator, but the thermometer had not been outside more than a second before it began falling.

"Good!" exclaimed Mr. Henderson, as he noted it. "The temperature is going down. I'd rather have it too cold than too hot. We can stand a minus fifty of cold better than two hundred and twelve of heat. We have fur garments with us."

"It is still going down," remarked Jack, as he saw the red column drop down past the thirty mark.

"Below freezing," added Mark.

The spirits fell in the tube until they touched twenty-eight degrees, and there they remained.

"Twenty-eight degrees," remarked Professor Henderson. "That isn't so bad. At least, we can stand that if we are warmly clad."

"Yes, but it will be colder to-night," said Jack. For they had landed on the moon in bright sunlight.

"To-night?" questioned the German scientist, with a smile.

"Yes, it's always colder when the sun goes down," went on the lad.

"You have forgotten one thing," said Mr. Henderson, with a smile at his young protege. "You must remember, Jack, that the nights and days here are each fourteen days long—that is, fourteen of our days."

"How's that?" asked Jack.

"Why," broke in Mark, who was a trifle better student than was his chum, "don't you remember that the moon rotates on its axis once a month, or in about twenty-eight days, to be exact, and so half of that time is day and half night, just as on our earth, when it revolves on its axis in twenty-four hours, half the time is day and half the time is night."

"Sure, I ought to have remembered," declared Jack.

"Mark is right," added Mr. Henderson. "And, as we have most fortunately arrived on the moon at the beginning of the long day, we will have fourteen days of sunshine, during which we may expect the temperature to remain at about twenty-eight degrees. But now about the atmosphere." "We will test that directly," went on the German. "It will take some time longer, though."

Various instruments were brought forth and thrust out of the opening in the side of the projectile, which opening was so arranged that it was closed hermetically while the instruments were put forth. Then the readings of the dials or scales were taken, and computations made. In fact, some of what corresponded to the moon's atmosphere was secured in a hollow steel cup and brought inside the Annihilator for analysis.

"Well," remarked Professor Roumann, as he bent over a test tube, the contents of which he had put through several processes, "I am afraid we cannot breathe on the moon."

"Can't breathe on it?" gasped Jack. "Then we can't go out and walk around it."

"I didn't say that," resumed the German, with a smile. "I said we couldn't breathe the moon's atmosphere. In fact there is nothing there that we would call atmosphere. There is absolutely no oxygen, and there are a number of poisonous gases that would instantly cause death if inhaled."

"Then how are we to get out and hunt for those diamonds, Professor?" went on Jack. "Gee whiz! if I'd known that, I wouldn't have come. This is tough luck!"

"Maybe the professor can suggest a way out of the difficulty, boys," spoke Mr. Henderson. "It certainly would be too bad if, after our perilous trip, we couldn't get out of our cage and walk around the moon."

"I think perhaps I can discover a way so that it will be safe to venture forth," said Mr. Roumann. "But I must first conduct some further experiments. In the meanwhile suppose you boys get out some fur-lined garments, for, though it is only twenty-eight degrees, we will need to be well clad after the time spent inside this warm projectile."

"It does look as if he expected to get us out," remarked Jack, as he and his chum went to where Andy Sudds was.

"Yes, you'll get a chance to pick up diamonds after all, Jack. That is, if there are any here."

"Of course there are diamonds. You wait and see," and then, with the help of the old hunter, they took from the store-room their fur garments.

It was half an hour before the warm clothes were sorted out, and then the boys went back to where the two professors were.

"Well," asked Jack cautiously, "can we go outside?"

"I think so," answered the German cheerfully. "But you must always be careful to carry one of these with you," and he handed to each of the boys a steel rod about two feet long, at the end of which was a small iron box, with perforations in the sides and top.

"What is this?" asked Jack. "It looks like a magician's wand."

"And that is exactly what it is," said Mr. Henderson. "As there is no atmosphere fit to breathe on the moon, we have been forced to make our own, boys. You each hold what may be called torches of life. To venture out without them would mean instant death by suffocation or poison."

"And will these save our lives?" asked Mark.

"Yes," said Mr. Roumann. "In the iron boxes on those rods are certain chemicals, rich in oxygen and other elements, which, when brought in contact with the gases on the moon, will dispel a cloud of air about whoever carries them—air such as we find on our earth. So, boys, be careful never to venture out without the torches of life. I had them prepared in anticipation of some such emergency as this, and all that was necessary was to put in the chemicals. This I have done, and now, if you wish, you may go out and stroll about the moon."



CHAPTER XX

ON THE EDGE OF A CRATER

There was a little hesitation after Professor Roumann had spoken. Even though he assured them all that it would be safe to venture out on the surface of the moon, with its chilling temperature and its poisonous "atmosphere" (if such it can be termed), there was an uncanny feeling about stepping forth into the midst of the desolation that was on every side.

For it was desolate—terribly so! Not a sound broke the stillness. There was no life—no motion—as far as could be seen. Not a tree or shrub relieved the rugged monotony of the landscape. It was like a dead world.

"And to think that people may have once lived here," observed Jack, in a low voice.

"Yes, and to think that there may be people on the other side of the moon even now," added Mark. "We must take a look if it's possible."

"Well," remarked Mr. Henderson, after a while, "are we going out and see what it's like or not."

"Of course, we are," said Jack. "Come on, Mark, I'm not afraid."

"Me either. Do we have to do anything to the torches to make them operate, Professor Roumann?"

"Merely press this lever," and the scientist showed them where there was one in the handle of the steel rod. "As soon as that is pressed, it admits a liquid to the chemicals and the oxygen gas is formed, rising all around you, like a protecting vapor. After that it is automatic."

"How long will the supply of chemical last?" inquired Jack.

"Each one is calculated to give out gas for nearly two weeks," was the reply; "possibly for a little longer. But come, I want to see how they work. Here is your life-torch, Professor Henderson, and there is one for you, too, Andy, and Washington."

"'Scuse me!" exclaimed the colored man hastily, as he started back toward the kitchen.

"Why, what's the matter?" asked Jack. "Don't you want to go out, and walk around the moon, and pick up diamonds?"

"Diamonds am all right," answered Washington, "but I jest done fo'got dat I ain't fed my Shanghai rooster to-day, an' I 'spects he's mighty hungry. You folks go on out an' pick up a few obde sparklers, an' when I gits de Shanghai fed I'll prognosticate myse'f inter conjunction wif yo' all."

"You mean you'll join us?" asked Mark.

"Dat's what I means, suah."

"Why, I do believe Washington's afraid!" cried Jack jokingly.

"Askeered! Who's afraid?" retorted the colored man boldly. "Didn't I done tole yo' dat I got t' feed my rooster? Heah him crowin' now? Yo' all go 'long, an' I'll meet yo' later," and with that Washington disappeared quickly.

"Well, he'll soon pluck up courage and come out," declared Professor Henderson. "Let him go now, and we'll go out and see what it is like on the moon."

"I hope we find those diamonds," murmured Jack, and Mark smiled.

In order not to admit the poisonous gases into the projectile, it was decided to leave the Annihilator and return to it by means of a double door, forming a sort of air lock. It was similar to the water lock used on the submarine. That is, the adventurers entered a chamber built in between the two steel walls of their craft. The interior door was then sealed shut automatically. Next the outer door was opened, and they could step directly to the surface of the moon and into the deadly atmosphere.

"Well, are we all ready?" asked Mr. Roumann, as he picked up one of the chemical torches.

"I guess so," responded Andy Sudds, who had his gun with him. "I hope I see some game. I haven't had a shot in a long while."

"You're not likely to up here," spoke Mr. Henderson. "Game is scarce on the moon, unless it's some of that green cheese Washington talked about."

They entered the air lock and fastened the door behind them. Then Professor Roumann pressed on the lever that swung open the outer portal.

"Hold your torches close to your head," he called. "The moon atmosphere may be too strong for us at first until we create a mist of oxygen about us."

Out upon the surface of the moon they stepped, probably the first earth beings so to do, though they had evidence that the inhabitants of Mars had preceded them.

For a moment they all gasped for breath, but only for a moment. Then the gas began to flow from the life-torches, and they could breathe as well as they had done while in the projectile, or while on the earth.

"Well, if this isn't great!" cried Jack, gazing about him.

"It certainly beats anything I ever saw," came from Mark.

"Wonderful, wonderful," murmured Professor Henderson. "We will be able to gain much valuable scientific knowledge here, Professor Roumann. We must at once begin our observations."

"I agree with you," spoke the German.

Andy Sudds said nothing. He was looking around for a sight of game, with his rifle in readiness. But not a sign of life met his eager eyes.

Once they were outside the projectile it was even more desolate than it had seemed when they looked from the observation windows. It was absolutely still. Not a breath of wind fanned their cheeks, for where there is no air to be heated and cooled there could be no wind which is caused by the differences of temperature of the air, the cold rushing in to fill the vacuum caused by the rising of the hot vapors. Clad in their fur-lined garments, which effectually defied the cold, the adventurers stepped out.

Over the rugged ground they went, gazing curiously about them. It was like being in the wildest part of the Canadian Rocky Mountains of our earth, and, in fact, the surface of the moon was not unlike the mountainous and hilly sections of the earth. There were no long ranges of rugged peaks, though, but rather scattered pinnacles and deep hollows, great craters adjoining immense, towering steeples of rocks, with comparatively level ground in between.

The life-torches worked to perfection. As our friends carried them, there arose about their bodies a cloud of invisible vapor, which, however, was as great a protection from the poisonous gases as a coat of mail would have been.

"This is great!" exclaimed Jack. "It's much better than to have to put on a diving-suit and carry a cylinder of oxygen or compressed air about on our shoulders."

They strolled away from the projectile and gazed back at it. Nothing moved—not a sound broke the stillness. There was only the blazing sunlight, which, however, did not seem to warm the atmosphere much, for it was very chilly. On every side were great rocks, rugged and broken, with here and there immense fissures in the surface of the moon, fissures that seemed miles and miles long.

"Well, here's where I look for diamonds," called Jack, as he stepped boldly out, followed by Mark. "Let's see who'll find the first sparkler."

"All right," agreed his chum, and they strolled away together, slightly in advance of the two professors and Andy, who remained together, the scientist discussing the phenomena on every side and the hunter looking in vain for something to shoot. But he had come to a dead world.

Almost before they knew it Jack and Mark had gone on quite some distance. Though they were not aware of it at that moment, it was much easier to walk on the moon than it was on the earth, for they weighed only one sixth as much, and the attraction of gravitation was so much less.

But suddenly Jack remembered that curious fact, and, stooping, he picked up a stone. He cast it from him, at the same time uttering a yell.

"What's the matter?" called Mark.

"Look how far I fired that rock!" shouted Jack. "Talk about it being easy! why, I believe I could throw a mile if I tried hard!"

"It goes six times as far as it would on the earth," spoke his chum, "and we can also jump six times as far."

"Then let's try that!" proposed Jack. "There's a nice level place over there. Come on, I'll wager that I can beat you."

"Done!" agreed Mark, and they hurried to the spot, their very walking being much faster than usual.

"I'll go first," proposed Jack, "and you see if you can come up to me." He poised himself on a little hummock of rock, balanced himself for a moment, and then hurled himself through space.

Prepared as he was, in a measure, for something strange, he never bargained for what happened. It was as if he had been fired from some catapult of the ancient Romans. Through the air he hurtled, like some great flying animal, covering fifty feet from a standing jump.

"Say, that's great!" yelled Mark. "Here I come, and I'll beat——"

He did not finish, for a cry of horror came from Jack.

"I'm going to fall into a crater—a bottomless pit! I'm on the edge of it!" yelled the lad who had jumped.

And, with horror-stricken eyes, Mark saw his chum disappear from sight beyond a pile of rugged rocks, toward which he had leaped. The last glimpse Mark had was of the life-torch, which Jack held up in the air, close to his head.

"Jack—in a crater!" gasped Mark, as he ran forward, holding his own life-torch close to his mouth and nose.



CHAPTER XXI

WASHINGTON SEES A GHOST

Advancing by leaps and bounds, and getting over the ground in a manner most surprising, Mark soon found himself on the edge of the great, yawning crater, into which his chum Jack had started to slide. I say started, for, fortunately, the lad had been saved from death but by a narrow margin.

As Mark gazed down into the depths, which seemed fathomless, and which were as black as night, he saw his friend clinging to a rocky projection on the side of the extinct volcano. Jack had managed to grasp a part of the rough surface as he slid down it after his reckless jump. He looked up and saw Mark.

"Oh, Mark, can't you save me?" he gasped. "Call Professor Henderson!"

"I'll get you up, don't worry!" called Mark, as confidently as he could. "Hold tight, Jack. What has become of your life-torch?"

"I have it here by me. I didn't drop it, and it's on a piece of the rock near my head. Otherwise I couldn't breathe. Oh, this place is fearfully deep. I guess it hasn't any bottom."

"Now, keep still, and don't think about that. Save your strength, hold fast, and I'll get you up."

But, having said that much, Mark was not so sure how next to proceed. It was going to be no easy task to haul up Jack, and that without ropes or other apparatus. Another matter that added to the danger was the necessity of keeping the life-torch close to one's face in order to prevent death by the poisonous gases.

Mark's first impulse was to hasten back and call the two professors, but he looked over the desolate landscape, and could not see them, and he feared that if he went away Jack might slip and fall into the unknown depths of the crater.

"I've got to get him out alone," decided Mark. "But how can I do it?"

He crawled cautiously nearer to the edge of the extinct volcano and looked down. A few loose stones, dislodged by his weight, rattled down the sides.

"Look out!" cried Jack quickly, "or you'll fall, too!"

"I'll be careful," answered Mark, and then he drew away out of danger, with a queer feeling about his heart, which was beating furiously. Mark had hoped to be able to make his way down the side of the crater to where his chum was and help him up. But a look at the steep sides and the uncertain footing afforded by the loose rocks of lava-like formation showed that this could not be done.