LOST ON THE MOON OR IN QUEST OF THE FIELD OF DIAMONDS

BY ROY ROCKWOOD



CHAPTER

I. A WONDERFUL STORY II. SOMETHING ABOUT OUR HEROES III. PREPARING FOR A VOYAGE IV. AN ACCIDENT V. THE WORK OF AN ENEMY VI. ON THE TRACK VII. MARK IS CAPTURED VIII. JACK IS PUZZLED IX. A DARING PLOT X. "HOW STRANGE MARK ACTS" XI. READY FOR THE MOON XII. MARK'S ESCAPE XIII. A DIREFUL THREAT XIV. OFF AT LAST XV. THE SHANGHAI MAKES TROUBLE XVI. "WILL IT HIT US?" XVII. TURNING TURTLE XVIII. AT THE MOON XIX. TORCHES OF LIFE XX. ON THE EDGE OF A CRATER XXI. WASHINGTON SEES A GHOST XXII. A BREAKDOWN XXIII. LOST ON THE MOON XXIV. DESOLATE WANDERINGS XXV. THE PETRIFIED CITY XXVI. SEEKING FOOD XXVII. THE BLACK POOL XXVIII. THE SIGNAL FAILS XXIX. THE FIELD OF DIAMONDS XXX. BACK TO EARTH—CONCLUSION



CHAPTER I

A WONDERFUL STORY

"Well, what do you think of it, Mark?" asked Jack Darrow, as he laid aside a portion of a newspaper, covered with strange printed characters. "Great; isn't it?"

"You don't mean to tell me that you believe that preposterous story, do you, Jack?" And Mark Sampson looked across the table at his companion in some astonishment.

"Oh, I don't know; it may be true," went on Jack, again picking up the paper and gazing thoughtfully at it. "I wish it was."

"But think of it!" exclaimed Mark. "Why, if such a thing exists, and if we, or some one else, should attempt to bring all those precious stones to this earth, it would revolutionize the diamond industry of the world. It can't be true!"

"Well, here It is, in plain print. You can read it for yourself, as you know the Martian language as well as I do. It states that a large field of 'Reonaris' was discovered on the moon near Mare Tranquilitatis (or Tranquil Ocean, I suppose that could be translated), and that the men of Mars brought back some of the Reonaris with them. Here, read it, if you don't believe me."

"Oh, I believe you, all right—that is, I think you have translated that article as well as you can. But suppose you have made some error? We didn't have much time to study the language of Mars while we were there, and we might make some mistake in the words. That article might be an account of a dog-fight on the red planet, instead of an account of a trip to the moon and the discovery of a field of Reonaris; eh, Jack?"

"Of course, I'm likely to have made an error, for it isn't easy to translate this stuff." And Jack gazed intently at the strangely printed page, which was covered with characters not unlike Greek. "I may be wrong," went on the lad, "but you must remember that I translated some other articles in this paper, and Professor Henderson also translated them substantially as I did, and Professor Roumann agreed with him. There is Reonaris on the moon, and I wish we could go there and get some."

"But maybe after you got the Reonaris it would turn out to be only common crystals," objected Mark.

"No!" exclaimed Jack. "Reonaris is what the Martians call it in their language, and that means diamonds. I'm sure of it!"

"Well, I don't agree with you," declared the other lad.

"Don't be cranky and contrary," begged Jack.

"I'm not; but what's the use of believing anything so wild and weird as that? It's a crazy yarn!"

"It's nothing of the sort! There are diamonds on the moon; and I can prove it!"

"Well, don't get excited," suggested Mark calmly. "I don't believe it; that's all. You're mistaken about what Reonaris is; that's what you are."

"I am not!" Jack had arisen from his chair, and seemed much elated. In his hand he held clinched the paper which had caused the lively discussion. It was as near to a disagreement as Jack Darrow and Mark Sampson had come in some time.

"Sit down," begged Mark.

"I'll not!" retorted Jack. "I'm going to prove to you that I'm right."

"How are you going to do it?"

"I'm going to get Professor Henderson and Professor Roumann to translate this article for you, and then you can ask them what Reonaris is. Guess that'll convince you; won't it?"

"Maybe; but why don't you ask Andy Sudds or Washington White to give their opinion?"

"Don't get funny," advised the other lad sharply, and then, seeing that his chum was smiling, Jack laughed, cooled down a bit, looked at the paper which he had crumpled in his hand, and said:

"I guess I was getting a little too excited. But I'm sure I'm right. Here's the paper I brought from Mars to prove it, and the only thing there's any doubt about is whether or not Reonaris means diamonds. I'll ask——"

At that moment the door of the library, in which Jack and Mark were seated, was cautiously opened, and a black, woolly head was thrust in. Then two widely-opened eyes gazed at the boys.

"What's the matter, Washington?" asked Jack, with a laugh.

"'Scuse me, Massa Jack," answered the colored man, "but did I done heah you' to promulgate some conversationess regarding de transmigatorability ob diamonds?"

"Do you mean, were we talking about diamonds?" inquired Mark.

"Dat's what I done said, Massa Mark."

"No, you didn't say it, but you meant it, I guess," went on Jack. "Yes, we were talking about diamonds, Washington. I know a place that's full of them."

"Where?" inquired the colored man, thrusting his head farther into the room, and opening his eyes to their fullest extent. "Ef it ain't violatin' no confidences, Massa Jack, would yo' jest kindly mention it to yo's truly," and Professor Henderson's faithful servant, who had followed him into many dangers, looked at the two boys, who, of late years, had shared the labors of the well-known scientist. "Where am dose diamonds, Massa Jack?"

"On the moon," was the answer.

"On de moon? Ha! Ha! Dat's a joke!" And Washington began to laugh. "On de moon! Ha! Ho!"

"Well, you can read it for yourself," went on the lad, tossing the paper over to the colored man. The latter picked it up, gazed at it, first from one side, and then from the other. Next he turned it upside down, but, as this did not make the article any clearer, he turned the paper back again. Then he remarked, with a puzzled air:

"Well, I neber could read without mah glasses, Massa Jack, so I guess I'll hab t' let it go until annoder time. Diamonds on de moon, eh? Dat's wonderful! I wonder what dey'll be doin' next? But I'se got t' go. Diamonds on de moon, eh? Diamonds on de moon!"

As Washington turned to leave the room, for he had entered it when Jack and Mark were talking to aim, the latter lad asked:

"Did you want to see us about anything particular, Wash?"

"Why, I suah did," was the reply, "I did come t' tell yo' dat Perfesser Henderson would be pleased to hold some conversations wid yo', but when Massa Jack done mentioned about dem diamonds, I clean fo'got it. Diamonds on de moon, eh?"

"Well, if the professor wants us we'd better go," suggested Mark. "Come on, Jack, and stop dreaming about Reonaris and the moonbeams. Get back to earth."

"All right; laugh if you want to," said Jack sturdily, "but the time will come, Mark, when you'll find out that I'm right."

"How?" asked Mark.

"I don't know, but I'm sure I can prove what I say."

The two boys were to have the wonderful diamond story demonstrated to them sooner than either expected. Following the colored man, the lads, Jack carrying the paper, made their way to the laboratory of Professor Henderson. His door was open, and the aged man, whose hair and beard were now white with age, was bending over a table covered with papers, chemical apparatus, test tubes, alembecs, Bunsen burners, globes, and various pieces of apparatus. Another man, not quite so old as was Mr. Henderson, was on the point of leaving the apartment.

"Ah, boys," remarked the older professor, as he caught sight of them, "I hope I didn't disturb you by sending for you."

"No; Jack and I were only having a red-hot discussion about diamonds on the moon," said Mark, with a laugh.

"Diamonds on the moon!" exclaimed Professor Henderson.

"Diamonds on the moon?" repeated his friend, Prof. Santell Roumann. "Is this a joke, boys?"

"Mark thinks so, but I don't!" cried Jack, enthusiastically. "Look here, Professor Henderson, and also Mr. Roumann. Here is one of the newspapers that we brought back with us in our projectile, the Annihilator, after our trip to Mars. I have been translating some of the articles in it, and to-night I came across one that told of a trip made by some of the inhabitants of Mars to the moon, in a sort of projectile, like ours, only more on the design of an aeroplane.

"They landed on the moon, the article states, and found a big field, or deposit, of Reonaris, which I claim are diamonds. Mark says I'm wrong, but, Professor Henderson, isn't Reonaris to the Martians what diamonds are to us?"

"It certainly is," agreed the older scientist, and he looked for confirmation to his scholarly companion.

"Reonaris is substantially a diamond," said Professor Roumann. "It has the same chemical constitution, and also the diamond's hardness and brilliancy. But I don't understand how any diamonds can be on the moon."

"You can read this for yourself," suggested Jack, passing over the paper, which was one of some souvenirs brought back from what was the longest journey on record, ever taken by human beings.

Mr. Roumann adjusted his glasses, and carefully read the article that was printed in such strange characters. As he perused it, he nodded his head thoughtfully from time to time. Then he passed the paper to Professor Henderson.

The older scientist was somewhat longer in going over the article, but when he had finished, he looked at the two boys, and said: "Jack is right! This is an account of a trip made to the moon by some of the Martians, who have advanced much further in the art of air navigation than have we. Some of the words I am not altogether familiar with, but in the main, that is what the paper states."

"And doesn't it tell about them finding a field of Reonaris?" asked Jack eagerly, for he was anxious to prove to his chum that he was right.

"Yes, it does," replied Mr. Henderson.

"And Reonaris is diamonds, isn't it?" asked Jack.

"It is," answered Professor Roumann gravely.

"Then," cried Jack, "what's to hinder us from going to the moon, and getting some of those diamonds? The Martians must have left some! Let's go to the moon and get them! We can do it in the projectile with which we made the journey to Mars. Let's start for the moon!"

For a moment there was silence in the laboratory of the scientist. It was broken by Washington White, who remarked:

"Good land a' massy! Annodder ob dem trips through de air! Well, I ain't goin' to no moon—no sah!! Ef I went dere, I'd suah get looney, an' I has troubles enough now wid'out dat, I suah has!" And, shaking his head dubiously, the colored man shuffled from the room.



CHAPTER II

SOMETHING ABOUT OUR HEROES

"Are you in earnest in proposing this trip?" asked Professor Henderson of Jack. The lad, with flushed face and bright eyes, stood in the centre of the apartment, holding the paper which the aged scientist had returned to him.

"I certainly am," was the reply. "It ought not to be a difficult undertaking, after our trip to the North Pole through the air, the one to the South Pole under water, our journey to the centre of the earth, and our flight to Mars. Why, a trip to the moon ought to be a little pleasure jaunt, like an automobile tour. Can't we go, Professor?"

"From the standpoint of possibility, I presume we could make a trip to the moon," the scientist admitted. "It would not take so long, nor would it be as dangerous, as was our trip to Mars. And yet, I don't know that I care to go. I am getting along in years, and I have money enough to live on. Even a field of diamonds hardly sounds attractive to me." Jack's face showed the disappointment he felt.

"And yet," went on the aged scientist with a smile, "there are certain attractions about another trip through space. I had hoped to settle down in life now, and devote my time to scientific study and the writing of books. But this is something new. We never have been to the moon, and——"

"There are lots of problems about it that are still unsolved!" cried Jack eagerly. "You will be able to discover if the moon has an atmosphere and moisture; and also what the other side—the one that is always turned away from us—looks like."

"It does sound tempting," went on the aged scientist slowly. "And we could do it in our projectile, the Annihilator. It is in good working order; isn't it, Professor Roumann?"

"Couldn't be better. If you ask me, I, for one, would like to make a trip to the moon. It would give me a better chance to test the powers of Cardite, that wonderful red substance we brought from Mars. I can use that in the Etherium motor. If you left it to me, I'd say, 'go to the moon.'"

"Well, perhaps we will," spoke Mr. Henderson thoughtfully.

"You'll go, too, won't you, Mark?" asked Jack.

"Oh, I'm not going to be left behind. I'll go if the rest do, but I don't believe you'll find any diamonds on the moon. If there ever were any, the Martians took them." For Mark had been partly convinced after the confirmation by the two professors of Jack's translation.

"I'll take a chance on the sparklers," said his chum. "But now, let's go into details, and figure out when we can start. It ought not to take very long to get ready."

As has been explained in detail in the other books of this series, Professor Amos Henderson and the two lads, Mark Sampson and Jack Darrow, had undertaken many strange voyages together. Sometimes they were accompanied by friends and assistants, while Washington White, a sort of servant, helper, and man-of-all-work, and Andy Sudds, an old hunter, always went with them.

Mark and Jack were orphans, who had been adopted by Professor Henderson, who spent all his time making wonderful machines for transportation, or conducting strange experiments.

The two boys had been rescued by Professor Henderson and Washington White from a train wreck. Although both boys were badly hurt, they were nursed back to health by the eminent scientist, who soon learned to care for the lads as though they had been his own sons.

They aided the professor, as soon as they were able, in constructing an airship, called the Electric Monarch, in which Professor Henderson hoped to be able to reach the North Pole. The boys thoroughly enjoyed the trip through the air, and had many thrills fighting the savage Eskimos. Finally, they succeeded in passing over the exact spot of the North Pole during a violent snowstorm.

Not satisfied with their experiences after conquering the North, the adventurers set out for the Antarctic regions in a submarine boat. This trip, even more remarkable than the first, took them to many strange places in the South Atlantic. They were trapped for a time in the Sargasso Sea, and they walked on the ocean floor in new diving suits, one of the professor's marvelous inventions.

It was on the voyage to the south that, coming to the surface one day, the adventurers saw a strange island in the Atlantic Ocean, far from the coast of South America. On it was a great whirlpool, into which the Porpoise, their submarine boat, was nearly drawn by the powerful suction.

The chasm might lead to the center of the earth, it was suggested, and, after thinking the matter over, on their return from the Antarctic, Professor Henderson decided to build a craft in which they might solve the mystery.

The details of the voyage they took in the Flying Mermaid, are told of in the third volume, entitled "Five Thousand Miles Underground." The Mermaid could sail on the water, or float in the air like a balloon. In this craft the travellers descended into the centre of the earth, and had many wonderful adventures. They nearly lost their lives, and had to escape, after running through danger of the spouting water, leaving their craft behind.

For some time they undertook no further voyages, and the two boys, who lived with Professor Henderson in a small town on the coast of Maine, were sent to attend the Universal Electrical and Chemical College. Washington remained at home to minister to the wants of the old professor, and Andy Sudds went off on occasional hunting trips.

But the spirit of adventure was still strong in the hearts of the boys and the professor. One day, in the midst of some risky experiments at college, Jack and Mark, as related in "Through Space to Mars," received a telegram from Professor Henderson, calling them home.

There they found their friend entertaining as a guest Professor Santell Roumann, who was almost as celebrated as was Mr. Henderson, in the matter of inventions.

Professor Roumann made a strange proposition. He said if the old scientist and his young friends would build the proper kind of a projectile, they could make a trip to the planet Mars, by means of a wonderful motor, operated by a power called Etherium, of which Mr. Roumann held the secret.

After some discussion, the projectile, called the Annihilator, from the fact that it annihilated space, was begun. It was two hundred feet long, ten feet in diameter in the middle, and shaped like a cigar. It consisted of a double shell of strong metal, with a non-conducting gas between the two sides.

Within it were various machines, besides the Etherium motor, which would send the projectile along at the rate of one hundred miles a second. This great speed was necessary in order to reach the planet Mars, which, at the time our friends started for it, was about thirty- five millions of miles away from this earth. It has since receded some distance farther than this.

Finally all was in readiness for the start to Mars. Professor Roumann wanted to prove that the planet was inhabited, and he also wanted to get some of a peculiar substance, which he believed gave the planet its rosy hue. He had an idea that it would prove of great value.

But, though every precaution was taken, the adventurers were not to get away from the earth safely. Almost at the last minute, a crazy machinist, named Fred Axtell, who was refused work on the projectile, tried to blow it up with a bomb. He partly succeeded, but the damage was repaired, and the start made.

Inside the projectile our friends shut themselves up, and the powerful motors were started. Off it shot, at the rate of one hundred miles a second, but the travellers were as comfortable as in a Pullman car. They had plenty to eat and drink, they manufactured their own air and water, and they slept when they so desired.

But Axtell, the crazy machinist, had hidden himself aboard, and, in mid-air, he tried to wreck the projectile. He was caught, and locked up in a spare room, but, when Mars was reached, he escaped.

The book tells how our friends were welcomed by the Martians, how they learned the language, saw many strange sights, and finally got on the track of the Cardite, or red substance, which the German professor, Mr. Roumann, had come so far to seek. This Cardite was capable of great force, and, properly controlled, could move great weights and operate powerful machinery.

Our friends wanted to take some back to earth with them, but when they attempted to store it in their projectile, they met with objections, for the Martians did not want them to take any. They had considerable trouble, and the crazy machinist led an attack of the soldiers of the red planet against our friends, the adventurers in the projectile.

Among the other curiosities brought away by our friends, was a newspaper printed in Mars, for the inhabitants of that place where much further advanced along certain lines than we are on this earth, but in the matter of newspapers they had little to boast of, save that the sheets were printed by wireless electricity, no presses being needed.

As told at the opening of this story, Jack had noticed on one of the sheets they brought back, an account of how some of the Martians made a trip to the moon, and discovered a field of Reonaris. This trip was made shortly before our friends made their hasty departure, and it was undertaken by some Martian adventurers on another part of the red planet than where the projectile landed, and so Professor Henderson and his friends did not hear of it at the time.

"Well, then, suppose we make the attempt to go to the moon," said Professor Roumann, after a long discussion in the laboratory. "It will not take long to get ready."

"I'd like to go," said Jack. "How about you, Professor Henderson? Oh, by the way, Washington said you wanted to see Mark and me, but I was so interested in this news item, that I forgot to ask what it as about."

"I merely wanted to inquire when you and Mark thought of resuming your studies at college," said the aged man, "but, since this matter has come up, it will be just as well if you do not arrange to resume your lessons right away."

"We can study while making the trip to the moon," suggested Mark.

"Not much," declared Jack, with a laugh. "There'll be too much to see."

"Well, we'll discuss that later," went on Mr. Henderson. "Practically speaking, I think the voyage can be made, and, the more I think of it, the better I like the idea. We will look over the projectile in the morning, and see what needs to be done to it to get it ready for another trip through space."

"Not much will have to be done, I fancy," remarked the German scientist. "But I want to make a few improvements in the Cardite motor, which I will use in place of the Etherium one, that took us to Mars."

A little later there came a knock on the rear door of the rambling old house where the professor lived and did much of his experimental work.

"I'll go," volunteered Jack, and when he opened the portal there stood on the threshold a small boy, Dick Johnson, one of the village lads.

"What is it you want, Dick?" asked Mark.

"Here's a note for you," went on the boy, passing over a slip of paper. "I met a man down the road, and he gave me a quarter to bring it here. He said it was very important, and he's waiting for you down by the white bridge over the creek."

"Waiting for who?" asked Jack.

"For Mark, I guess; but I don't know. Anyhow, the note's for him."

"Hum! This is rather strange," mused Mark.

"What is it?" asked Jack.

"Why, this note. It says: 'It is important that I see you. I will wait for you at the white bridge.' That's all there is to it."

"No name signed?" asked Jack.

"Not a name. But I'll just take a run down and see what it is. I'll not be long. Much obliged, Dick."

The boy who had brought the note turned to leave the house, and Mark prepared to follow. Jack said:

"Let me see that note."

He scanned it closely, and, as Mark was getting on his hat and coat, for the night was chilly, his chum went on:

"Mark, if I didn't know, that we had left Axtell, the crazy machinist, up on Mars, I'd say that this was his writing. But, of course, it's impossible."

"Of course—impossible," agreed Mark.

"But, there's one thing, though," continued Jack.

"What's that?" asked Mark.

"I don't like the idea of you going off alone in the dark, to meet a man who doesn't sign his name to the note he wrote. So, if you have no objections, I'll go with you. No use taking any chances."

"I don't believe I run any risk," said Mark, "but I'll be glad of your company. Come along. Maybe it's only a joke." And the two lads started off together in the darkness toward the white bridge.



CHAPTER III

PREPARING FOR A VOYAGE

"Seems like rather an odd thing; doesn't it?" remarked Jack, as he and his chum walked along.

"What?"

"This note."

"Oh, yes. But what made you think the writing looked like that of the crazy machinist who tried to wreck the projectile?"

"Because I once saw some of the crazy letters he sent us, and he wrote just like the man who gave Dick this note. But come on, let's hustle, and see what's up."

In a few minutes they came in sight of the white bridge, which was about a quarter of a mile down the road from the professor's house. The two boys kept well together, and they were watching for a first sight of the man in waiting.

"See anything?" asked Jack.

"No; do you?"

"Not a thing. Wait until we get closer. He may be in the shadow. It's dark now."

Almost as Jack spoke, the moon, which had been hidden behind a bank of clouds, peeped out, making the scene comparatively bright. The boys peered once more toward the bridge, and, as they did so, they saw a figure step from the shadows, stand revealed for an instant in the middle of the structure, and then, seemingly after a swift glance toward the approaching chums, the person darted off in the darkness.

"Did you see that?" cried Jack.

"Sure," assented Mark. "Guess he didn't want to wait for us. Why, he's running to beat the band!"

"Let's take after him," suggested Jack, and, nothing loath, Mark assented. The two lads broke into a run, but, as they leaped forward, the man also increased his pace, and they could hear his feet pounding out a tattoo on the hard road.

The two youths reached the bridge, and sped across it. They glanced hastily on either side, thinking possibly the man might have had some companions, but no one was in sight, and the stranger himself was now out of view around a bend in the highway.

"No use going any farther," suggested Jack, pulling up at the far side of the bridge. "There are two roads around the bend, and we couldn't tell which one he'd take. Besides, it might not be altogether safe to risk it."

Mark and Jack, on their return, told Professor Henderson and the German scientist something of their little excursion.

"But who could he have been?" asked Mr. Roumann. "Perhaps if you ask the boy who brought the note he can tell you."

"We'll do it in the morning," decided Mark.

"It's peculiar that he wanted Mark to meet him," spoke Amos Henderson. "Have you any enemies that you know of, Mark?"

"Not a one. But what makes you think this man was an enemy, Professor?"

"From the fact that he ran when he saw you and Jack together. Evidently he expected to get Mark out alone."

They discussed the matter for some time, and then the boys and the scientists retired to bed, ready to begin active preparations on the morrow, for their trip to the moon.

There was much to be done, but their experience in making other wonderful trips, particularly the one to Mars, stood the travellers in good stead. They knew just how to go to work.

To Washington was entrusted the task of preparing the food supply, since he was to act as cook. Andy Sudds was instructed to look after the clothing and other supplies, except those of a scientific nature, while the two young men were to act as general helpers to the two professors.

As the Annihilator has been fully described in the volume entitled, "Through Space to Mars," there is no need to dwell at any length on the construction of the projectile in which our friends hoped to travel to the moon. Sufficient to say that it was a sort of enclosed airship, capable of travelling through space—that is, air or ether—at enormous speed, that there were contained within it many complicated machines, some for operating the projectile, some for offence or defence against enemies, such as electric guns, apparatus for making air or water, and scores of scientific instruments.

The Annihilator was controlled either from the engine room, or from a pilot house forward. As for the motive power it was, for the trip to the moon, to be of that wonderful Martian substance, Cardite, which would operate the motors.

The projectile moved through space by the throwing off of waves of energy, similar to wireless vibrations, from large plates of metal, and these plates were the invention of Professor Roumann.

Perhaps to some of my readers it may seem strange to speak so casually of a trip to the moon, but it must be remembered that our friends had already accomplished a much more difficult journey, namely, that to Mars. So the moon voyage was not to daunt them.

Mars, as I have said, was thirty-five millions of miles away from the earth when the Annihilator was headed toward it. To reach the moon, however, but 252,972 miles, at the most, must be traversed—a little more than a quarter of a million miles. As the distance from the earth to the moon varies, being between the figures I have named, and 221,614 miles, with the average distance computed as being 238,840 miles, it can readily be seen that at no time was the voyage to be considered as comparing in distance with the one to Mars.

But there were other matters to be taken into consideration, and our friends began to ponder on them in the days during which they made their preparations.



CHAPTER IV

AN ACCIDENT

Washington White was kept busy getting together the food for the voyage, and he had about completed his task, while Andy Sudds announced one morning that his department was ready for inspection, and that he thought he would go hunting until the projectile was ready to start.

"Well, if you see anything of that queer man who sent me the note, just ask him what he meant by it," suggested Mark, for inquiry from the boy who had brought the message, developed the fact that Dick did not know the man, nor had he ever seen him before. He was a stranger in the neighborhood. But, as nothing more resulted from it, the two lads gave the matter no further thought.

"How soon before we will be ready to start?" asked Jack one day, while he and his chum, with the two professors, were working over the projectile, which was soon to be shot through space.

"In about two weeks," replied Mr. Roumann. "I want to make a few changes in the Cardite plates, which will replace the ones used on the Etherium motor. Then I want to test them, and, if I find that they work all right, as I hope, we will seal ourselves up in the Annihilator, and start for the moon."

"Are you going to try to go around it, and land on the side turned away from us?" asked Mark, who had been studying astronomy lately.

"What do you mean by that?" asked Jack. "Doesn't the moon turn around?"

"Not as the earth does," replied his chum; "or, rather, to be more exact, it rotates exactly as the earth does, on its axis; but, in doing this it occupies precisely the same time that it takes to make a revolution about our planet. So that, in the long run, to quote from my astronomy, it keeps the same side always toward the earth; and today, or, to be more correct, each night that the moon is visible, we see the same face and aspect that Galileo did when he first looked at it through his telescope, and, unless something happens, the same thing will continue for thousands of years."

"Then we've never seen the other side of the moon?" asked Jack.

"Never; and that's why I wondered if the professor was going to attempt to reach it. Perhaps there are people there, and air and water, for it is practically certain that there is neither moisture nor atmosphere on this side of Luna."

"Wow! Then maybe we'd better not go," said Jack, with a shiver. "What will we do, if we get thirsty?"

"Oh, I guess we can manage, with all the apparatus we have, to distill enough water," said Professor Henderson, with a smile. "Then, too, we will take plenty with us, and, of course, tanks of oxygen to breathe. But it will be interesting to see if there are people on the moon."

"If there are any, they must have a queer time," went on Mark.

"Why?" asked Jack, who wasn't very fond of study.

"Why? Because the moon is only about one forty-ninth the size of the earth. Its diameter is 2,163 miles—only a quarter of the earth's—and, comparing the force of gravity, ours is much greater. A body that weighs six pounds on the earth, would weigh only one pound on the moon, and a man on the moon could jump six times as high as he can on this earth, and throw a stone six times as far."

"What's dat?" inquired Washington White quickly, nearly dropping some packages he was carrying into the projectile. "What was yo' pleased t' saggasiate, in remarkin' concernin' de untranquility ob the densityness ob stones jumpin' ober a man what is six times high?" he asked.

"Do you mean what did I say?" asked Mark solemnly.

"Dat's what I done asked yo'," spoke the colored man gravely.

"Well, you didn't, but perhaps you meant to," went on the youth, and he repeated his remarks.

"'Scuse me, I guess I'd better not go on dish yeah trip after all," came from Washington.

"Why not?" demanded Professor Henderson.

"'Cause I ain't goin' t' no place whar ef yo' wants t' take a little jump yo' has t' go six times as far as yo' does when yo' is on dis yeah earth. An' s'posin' some ob dem moon men takes a notion t' throw a stone at me? Whar'll I be, when a stone goes six times as far as it does on heah? No, sah, I ain't goin'!"

"But perhaps there are no men on the moon," said Mark quickly. "It is only a theory of astronomers that I'm talking about."

"Oh, only a theory; eh?" asked Washington quickly.

"That's all."

"Oh, if it's only a theory, den I reckons it's all right," came from the colored man. "I didn't know it were a theory. Dat makes it all right. It's jest in theory, am it, Massa Mark, dat a stone goes six times as far?"

"That's all."

"Oh, well, den, why didn't yo' say so fust, dat it was only a theory? I don't mind theories. I—I used t' eat 'em boiled an' roasted befo' de wah." And, with a contented smile on his face, Washington went into the projectile, to finish stowing things away in his kitchen lockers.

The big projectile was housed in the shed where it had been constructed, and the professor and the boys were working over it there, carefully guarded from curious eyes, for the German inventor did not want the secret of his Cardite motor to become known.

The work went on from day to day, good progress being made. The boys were of great assistance, for they were practical mechanics, and had had considerable experience.

"Well, I shall try the Cardite motor to-morrow," announced Professor Roumann one night, after a hard day's work on the projectile.

"Do you think it will work?" asked Mr. Henderson.

"I think so, yes. My experiments have made me hopeful."

"And if it does work, when can we start?" asked Jack.

"Two days later; that is, if everything else is in readiness, the food and other, supplies on board."

"They are all ready to be stowed away," said Andy Sudds, who had been hunting all day.

It was an anxious assemblage that gathered inside the big shed the next day, to watch Professor Roumann try the Cardite motor. Would it work as well as had the Etherium one? Would it send them along through space at enormous speed? True, they would not have to travel so far, nor so fast, but more power would be needed, since, as it was feared no food, water, nor air could be had on the moon, many more supplies were to be taken along than on the trip to Mars, and this made the projectile heavier.

"We will test the Cardite in this small motor first," said Mr. Roumann, as he pointed to a machine in the projectile used for winding a cable around a windlass when there was necessity for hauling the Annihilator about, without sending it into the air.

Into the receptacle of the motor, the German professor placed some of the wonderful red substance he had secured from Mars. Then he closed the heavy metal box that held it, and, looking about to see if all was in readiness, he motioned to those watching him that he was about to shift the lever that would start the motor.

"If it works as well as I hope it will," he said, "it ought to pull the projectile slowly across the shop—a task that would be impossible in a motor of this size, if operated by electricity, gasoline, or any other force at present in use. And, if this small motor will do that, I know the large ones will send us through space to the moon. All ready, now."

Slowly the professor shoved over the lever, while Jack, Mark and the others watched him carefully. They were standing back of him, in the engine room of the projectile.

There was a clicking sound as the lever snapped into place. This was succeeded by a buzzing hum, as the motor began to absorb the great power from the red substance, which was not unlike radium in its action. There was a trembling to the great projectile.

"She's moving!" cried Jack.

Hardly had he spoken when there was a flash of red fire, a sound as of a bursting bomb, and everyone was knocked from his feet, over backward, while Professor Roumann was hurled the entire length of the engine room.

"The Cardite motor has exploded!" cried Mark. "Professor Roumann is killed!"



CHAPTER V

THE WORK OF AN ENEMY

Jack's first act, on arising from amid a mass of tools, into which he had been tossed by the explosion, was to run to where Professor Roumann lay in a semi-conscious condition. An instant later Mark slowly arose, and made his way to where Professor Henderson was rubbing his forehead in a dazed fashion.

"Are you hurt?" asked Mark, of his aged friend.

"I think not," answered Mr. Henderson slowly, "but I fear Mr. Roumann is. See to him; I'm all right."

"He's breathing," cried Jack, who had bent over the German. "He isn't dead, at any rate."

"But he may be, unless he gets attention," said Professor Henderson. "Get my medicine chest, Mark, and we'll see what we can do for him."

Jack had raised the head of the injured man on his arm, and was giving him some water from a glass. This partially revived the German, and he opened his eyes. He looked around, into the faces of his friends, as if scarcely comprehending what had happened, and then, as his gaze wandered toward the disabled Cardite motor, he exclaimed:

"Some enemy has done this! The motor was tampered with. The resistance block was loosened, and that caused the force of the Cardite to shoot out at the rear. We must watch out for the work of this enemy!"

"Don't distress yourself about that now," urged Mr. Henderson. "Are you badly hurt? Do you need a doctor?"

The German slowly drank the rest of the water which Jack gave him, and then gradually arose to a standing position.

"I am all right," he said faintly, "except that I feel a trifle dizzy. Something hit me on the head, and the fumes from the Cardite took away my breath for a moment. I think I shall be all right soon."

"Here is the medicine chest!" exclaimed Mark, coming back into the engine room. Mr. Henderson poured out some aromatic spirits of ammonia into a graduated glass, added a little water, and gave it to his fellow, inventor, who, after drinking it, declared that he felt much better. There was a cut on his forehead, where a piece of the broken motor had struck him, but, otherwise, he did not seem injured externally.

As for the boys, they were only stunned, nor was Mr. Henderson more than momentarily shocked. In a few minutes the German professor was almost himself again.

"We must try to discover who our enemy is," he said earnestly, as he looked over the disabled motor. "He might have blown up the whole projectile by tampering as he did with the machinery. Had I been testing the large, instead of the small motor, there would have been nothing left of the Annihilator, or us, either. Who could have done this? If that crazy machinist is around again——"

"I don't believe he could get here from Mars," interrupted Jack, with a smile.

"Hardly," added Mark.

"No, I guess he is still on the Red Planet, so it couldn't have been him," went on Mr. Roumann. "But it was some one."

Jack and Mark at once thought of the odd man who had sent Mark the note, and then had run away.

"Could it have been him?" suggested Jack.

"It's possible," remarked Professor Henderson. "We must be on our guard. I wonder if Washington——"

At that moment there sounded a violent pounding on the exterior of the projectile, and the voice of the colored man could be heard calling:

"Am anything de mattah? Andy Sudds an' I is out heah, an' we heard suffin goin' on in dere. Am anybody hurted?"

"It's all over now, Wash," replied Jack, for the two boys, and the two professors, had shut themselves up in the projectile while they conducted the experiment. Jack opened the door of the Annihilator and stepped out, being met by the colored man and the old hunter.

"You haven't seen any suspicious characters around, have you, Wash?" asked Mark. "Some one has been tampering with a motor, and it exploded."

"Nobody's been around since I've been here," announced Andy Sudds, with a significant glance at his gun.

"Maybe it's some ob dem moon-men, what don't laik de idea ob us goin' dere arter dere diamonds," volunteered the colored man.

"Perhaps," admitted Jack, with a smile. "But certainly some one has been around here who had no business to be, and we must find out who it was. Better take a look around, Wash."

"I'll help him," said Andy, and, with his rifle in readiness for any intruders, the old hunter followed the colored man outside the big shed.

Meanwhile Professor Roumann and Mr. Henderson were carefully examining the exploded motor.

"I should have looked at the breech plug before turning on the power," said the German, "but I had no reason to suspect that anything was wrong." He went on to explain that the explosion was something like that which occurs when the breech-block of a big navy gun is not properly in place. The force of the Cardite, instead of being directed against the piston-heads of the motor, shot out backward, and almost into the face of the professor, who was operating the machine.

"But what could be their object?" asked Mark. "Who would want to injure us, or damage the projectile?"

"Some enemy, of course," declared Jack. "But who? The crazy machinist is out of it, and as for that man who sent the note to you, he seemed too big a coward to attempt anything like this."

"Some one evidently sneaked in here and loosened the breech-plug," went on Mark, "and it was evidently done with the idea of delaying us. The enemy could not have desired to utterly disable the projectile, or else he would have tampered with the large motor, instead of the small one."

"Yes, the object seems to have been to delay us," admitted Professor Henderson; "yet, I can't understand why. Whoever did it evidently knows something about machinery."

"I hope they did not discover the secret of my Cardite motor," said Professor Roumann quickly.

"They hardly had time," declared Mark. "We have been in or around the projectile nearly every minute of the day, and whoever it was, must have watched his chance, slipped in, stayed a few seconds, and then slipped out again."

They went carefully over the entire projectile, but could find no further damage done. Nor were there any traces of the person who had so nearly caused a tragedy. Washington and Andy, after a careful search outside the shed, had to admit that they had no clews.

"Well, the only thing to do is to go to work and build a new small motor," announced Professor Roumann, after once more looking over the debris of the one that had exploded.

"Will it take long?" asked Jack.

"About two weeks. Fortunately, I can use some of the parts of this one, or we would be delayed longer."

"Still two weeks is quite a while," suggested Mark. "Perhaps there'll be no diamonds left on the moon when we get there, Jack," and he smiled jokingly.

"Oh, I fancy there will. The article in the paper from Mars says there was a whole field of them."

"This brings up another matter," said Professor Henderson. "What will happen if we bring back bushels and bushels of diamonds?—which, in view of what the paper says, may be possible. We will swamp the market, and the value of diamonds will drop."

"Then we must not throw them upon the market," decided Professor Roumann. "The scarcity of an article determines its value. If we do find plenty of diamonds, it will give me a chance to conduct some experiments I have long postponed because of a lack of the precious stones. We can use them for laboratory purposes, and need not sell them. In fact, with the Cardite we brought back from Mars, we have no lack of money, so we really do not need the diamonds."

It was decided, in view of the shock and upset caused by the explosion, that no further work would be done that day, and so, after carefully locking the shed, and posting Andy on guard with his gun, the boys and the professor went into the house to discuss matters, and plan for work the next day.

"Mark," said Jack in a low voice, as they followed the two scientists, "I think it's up to us to try to find that mysterious man who sent the note. I think he did this mean trick!"

"So do I, and we'll have a hunt for him. Let's go now."



CHAPTER VI

ON THE TRACK

The two boys gazed after Professors Henderson and Roumann. The scientists were deep in a discussion of various technical matters, which discussion, it was evident, made them oblivious to everything else.

"Shall we ask them?" inquired Jack in a whisper.

"No; what's the use?" queried Mark. "Let's go off by ourselves, and perhaps we can discover something. If we could once get on the trail of the man who wrote the note, I think we could put our hands on the person responsible for the blowing up of the motor."

"I agree with you. We won't bother them about our plans," and he waved his hand toward the scientists, who had, by this time, entered the house.

"In the first place," said Mark, as he and his chum turned from the yard, and walked along a quiet country road, "I think our best plan will be to find Dick Johnson, and ask him just where it was he met the man who gave him a quarter to bring the note to me."

"What for?" asked Jack.

"Why, then, we can tell where to start from. Perhaps Dick can give us a description of the man, or tell from what direction he came. Then we'll know how to begin on the trail."

"That's a good idea, I guess. We know where he disappeared to, or, rather, in nearly what direction, so that will help some."

"Sure. Well, then, let's find Dick."

To the inquiries of the two lads from the projectile, Dick Johnson replied that, as he had asserted once before, that the man was a stranger to him.

"He was tall, and had a big black mustache," Dick described, "but he kept his hat pulled down over his eyes, so I couldn't see his face very well. Anyhow, it was dark when I met him."

"Where did you meet him?" asked Mark.

"Not far from your house. He was standing on the corner, where you turn down to go to the woollen mill, and, as I passed him, he asked me if I wanted to earn a quarter."

"Of course you said you did," suggested Jack.

"Sure," replied Dick. "Then he gave me the note, and told me where to take it, and I did. That wasn't wrong, was it?"

"No; only there seems to be something queer about the man, and we want to find out what it is," replied Mark.

"What was the man doing when you saw him?" asked Jack.

"Standing, and sort of looking toward your house."

"Looking toward our house?" repeated Jack. "Was he anywhere near the big shed where we build the machines?"

"Well, I couldn't say. Maybe he might have been."

"I guess that's all you can tell us," put in Mark, with a glance at his chum, to warn him not to go too much into details with Dick, for they did not want it known that some enemy had tried to wreck the projectile.

"Yes, I can't tell you any more," admitted the small lad.

"Well, here's a quarter for what you did tell us," said Jack, "and if you see that man again, and he gives you a note for us, just keep your eye on him, watch where he goes, and tell us. Then you will get a half- dollar."

"Gee! I'll be on the watch," promised Dick, his eyes shining at the prospect of so much money.

"Come on," suggested Jack to his chum, after the small chap had departed. "Let's go down by the white bridge and make some inquiries of people living in that vicinity. They may have seen a stranger hanging around, and, perhaps we can get on his trail that way."

"All right," agreed Mark, and they walked on together.

They had gone quite a distance away from the bridge, and had made several inquiries, but had met with no success, and they were about to give up and go back home.

"I know one person we haven't inquired of yet," said Mark, as they tramped along.

"Who's that?"

"Old Bascomb, who lives alone in a shack on the edge of the creek. You know the old codger who traps muskrats."

"Oh, sure; but I don't believe he'd know anything. If he did, he's so cranky he wouldn't tell you."

"Maybe he would, if we gave him a little money for some smoking tobacco. It's worth trying, anyhow. Bascomb goes around a great deal, and he may have met a strange man in his travels."

"Well, go ahead; we'll ask him."

The muskrat trapper did not prove to be in a very pleasant frame of mind, but, after Mark had given him a quarter, Bascomb consented to answer a few questions. The boys told him about looking for a strange man, describing him as best they could, though they did not tell why they wanted to find him.

"Wa'al, now, I shouldn't be surprised but what I know the very fellow you want," said the trapper. "I met him a couple of days back, an' I think he's still hanging around. Fust I thought he was after some of my traps, but when I found he wa'ant, I didn't pay no more attention to him. He looked jest like you say."

"Where was he?" asked Jack eagerly.

"Walkin' along the creek, sort of absent-minded like."

"You don't know where he lives, or whether he is staying in this vicinity, do you?" inquired Mark.

"Ya'as, I think I do," replied the trapper.

"Where?" cried Jack eagerly.

"Wa'al, you know the old Preakness homestead, down by the bend of the creek, about four mile below here?"

"Sure we know it," answered Mark. "We used to go in swimming not far from there."

"Wa'al, the old house has been deserted now for quite a spell," went on the trapper, "and there ain't nobody lived in it but tramps. But the other night, when I was comin' past, with a lot of rats I'd jest taken out of my traps, I see a light in the old house. Thinks I, to myself, that there's more tramps snoozin' in there, and I didn't reckon it was none of my business, so I kept on. But jest as I was walking past the main gate, some one come out of the house and hurried away. I had a good look at him, an'——"

"Who was it?" asked Mark impatiently, for the old trapper was a slow talker.

"It was the same man you're lookin' for," declared Bascomb. "I'm sure of it, an' he's hangin' out in the old Preakness house. If you want t' see him, why don't you go there?"

"We will!" cried Jack. "Come on, Mark. I think we're on the trail at last."



CHAPTER VII

MARK IS CAPTURED

Eagerly the boys hurried forward, intent on making the best time possible to the old Preakness homestead, which was a landmark for miles around, and which, in its day, had been a handsome house and estate. Now it was fallen into ruins, for there was a dispute among the heirs, and the property was in the Chancery Court.

"Do you think we'll find him there?" asked Mark, as they made their way along the dusty highway. "Hard to tell. Yet, if he's hanging out in this neighborhood, that would be as good a place as any, for him to hide in."

"I wonder who he can be, anyhow? And how he knows me?"

"Give it up. Evidently he isn't a tramp, though he stays in a place where there are plenty of the Knights of the Road."

The boys increased their pace, and were soon on the main road leading to the Preakness house, and about a mile away from it. "We'll soon be there now," remarked Jack. "Then we'll see if we can find that man."

As he spoke, the lad put his hand in his pocket, and, a moment later, he uttered a startled cry.

"What's the matter?" asked Mark, in some alarm.

"Matter? Why, gee whiz! If I haven't forgotten to send that telegram Professor Henderson gave me! It's to order some special tools to take along on our trip to the moon. They didn't come, and the professor wrote out a message urging the factory to hurry the shipment. He gave it to me to send, just before the accident to the motor, but when that happened it knocked it out of my mind, I guess. I stuck the telegram in my pocket, and here it is yet," and Jack drew forth a crumpled paper. "Wouldn't that make you tired?" he asked. "It's important, and ought to go at once. The professor won't like it."

"I'll tell you what to do," suggested Mark, after a moment's thought. "The telegraph office isn't so far away from here. You can cut across lots, and be there in fifteen or twenty minutes. Tell 'em to rush the message, and it may be in time yet. Anyhow, we're going to be delayed because of the accident to the motor, so it won't make so much difference. But come on, let's start, and we can hurry back."

"I guess that's the best plan," remarked Jack dubiously, for he did not fancy a half-hour's tramp across the fields and back again. Then, as he thought of something else, he called out:

"Say, Mark, there's no use of both of us going to the telegraph office. I'll go alone, as it's my fault, and you can stay here, and watch to see if that strange man appears on the scene. I'll not be long, and you can wait for me here."

"How would it be if I went on a little nearer to the Preakness house?" asked Mark. "I can meet you there just as well as here, and something may develop."

"Good idea! You go on, and when I come back, I'll take the road that leads through the old slate quarry, and save some time that way. I'll meet you right near the old barn that stands on the Gilbert property, just before you reach the Preakness grounds."

"All right; I'll be there, but don't run your legs off. We're out for all day, and there isn't anything that needs to be done at home, or around the projectile, so take your time."

"Oh, I'll not go to sleep," declared Jack. "I want to see if we can't solve the mystery of the man who writes such queer notes."

Jack started off across the fields at a swift pace, while Mark strolled on down the road, in the direction of the old Preakness house. He was thinking of many things, chiefly of the wonderful journey that lay before them, and he was wondering what the moon would look like when they got to it.

That it would be a wild, desolate place, he had no doubt, for the evidences of the telescopes of astronomers pointed that way, and, as is well known, the most powerful instruments can now bring the moon to within an apparent distance of one hundred miles of the earth. This is true of the Lick telescope, which has a magnifying power of 2,500 and an object lens a yard across.

But, with this powerful telescope, it has been impossible to distinguish any such objects as forests, cities, or any evidences of life on the moon—that is, on the side that has always been turned toward us.

Almost unconsciously, Mark went on faster than he intended, and, before he knew it, he had arrived at the barn where he had promised to wait for his chum. Mark looked at his watch, and found that he would still have some time to linger before he could expect Jack to return. He sat down on a stone beside the fence, and looked about him. The day was warm for fall, and the last of the crickets were chirping away, while, in distant fields, men could be seen husking corn, or drawing in loads of yellow pumpkins.

"I wonder if we'll have pumpkin pie on the moon," thought Mark. "Though, of course, we won't. I guess all we'll have to eat will be what Washington takes along in the projectile—that is, unless we find people on the other side of the place."

He sat on the stone for some minutes longer, and then, tiring of the inactivity, he arose and strolled about. Something seemed to draw him in the direction of the old house, which he knew was just around the bend in the road.

"I guess there wouldn't be any harm in my going along and taking a peep at it," mused the lad. "It will be some time before Jack returns, and I may be able to catch a glimpse of our man. I think I'll go up where I can see the place, and I can come back in time to meet Jack. I'll do it. Maybe the fellow might escape while I'm waiting."

Mark thus tried to justify himself for his action in not keeping to his agreement with his chum. Of course it was not an important matter, Mark thought, though the results of his simple action were destined to be more far-reaching than he imagined. He thought he would be back in time to meet Jack, and so he strolled on, going more cautiously now, for, in a few minutes he would come in sight of the old, deserted house, and he did not know what he might find there.

Mark's first sight of the Preakness homestead was of two old stone posts, that had once formed a fine gateway. The posts were in ruins, now, and half fallen down, being covered with Virginia creeper, the leaves of which were now a vivid red, mingled with green.

"Nothing very alarming there," said Mark, half aloud. He could just catch a glimpse of the roof of the house over the tops of the trees, which had not yet shed all their leaves. "Guess I'll go on a little farther. Maybe our friend, the enemy, is sitting on the front porch, sunning himself."

Past the old gateway Mark continued, intending to proceed along the highway until he got directly in front of the old mansion. There, he knew, he would have a good view, unobstructed by trees or shrubbery.

When the lad got to this place in the road, he paused, and stooped over, as if tying the lace of his shoe, for it was his intention to pass himself off, if possible, as a casual passer-by, so that in case the mysterious man should be in the house, his suspicions would not be aroused by seeing the youth to whom he had written the note staring in at him.

And, while he was apparently fussing with his shoe, Mark was narrowly eying the old house.

"Not a very inviting place," thought Mark. "I don't see why any man who could afford anything better, would stay there—unless he has some strong motive for lingering in this section. And that's probably what this fellow has, and I'd like to discover it. Well, I don't see any signs of him, so I guess I might as well go back, and wait for Jack. He'll be along soon."

He stood up, took a good look at the house, and was about to retrace his steps down the highway, when he saw the sagging front door of the old mansion slowly open. It creaked on the rusty hinges, and Mark stared with all his might as he saw a man emerge, a man who did not look like a tramp, for his clothes were of good material and cut, and fit him well. Nor did he wear a stubbly growth of beard, but, on the contrary, his face was clean shaven. The man was about Mark's size, perhaps a little taller, and nearly as stout. He stood on the sagging porch, and gazed off toward the road.

"Well, if that's the man Dick Johnson got the note from he's changed mightily in appearance," thought Mark, as he looked at the fellow. "He isn't very tall, and he hasn't any black mustache. But of course he may have shaved that off, and I suppose in the dark, and when one is in a hurry to earn a quarter, it's hard to say whether a man is tall or short. I wonder if this can be the person we're looking for?"

Mark hardly knew what to do. He stood in the road, undecided, and fairly stared at the man, who had left the porch, and was walking down the weed-grown path. He was looking straight at Mark, but if the stranger was the person who had written the note, and if he recognized the lad, he gave no sign to that effect.

"Good afternoon," said the man, as he paused at the gap in the front wall, where once a gate had been. "Pleasant day, isn't it."

"Ye—yes," stammered Mark, wondering what to say next.

"Live around here?" went on the man.

"Not very far off."

"Ah, then you know this old shack?"

"Well, I don't get over here, very often. Do you live here?" ventured Mark boldly, determining to do some questioning on his own account.

"Me live here?" cried the man, as if indignant "Well, hardly! I was just passing, and, happening to see the old place, and having a fondness for antiques, I stepped in. But it is in bad shape. I should say tramps make it their hangout."

"It has that name," said Mark.

There was a pause for a moment, and the lad was a trifle embarrassed. The man was gazing boldly at him.

"I guess I've made a mistake," thought Mark. "This can't be the man we want. He doesn't live here, and he doesn't look like him. I'd better be getting back to meet Jack."

"Are you engaged at anything in particular?" questioned the man taking a few steps nearer the youth.

"No, I'm not working, but I expect to take a trip, shortly, with some friends of mine," answered Mark.

"Ah, is that so?" and there was polite inquiry in the man's voice. "Are you going far?"

"Quite a distance." Mark wondered what the man would say if he told him he was going to the moon.

"I wonder if you would do me a favor?" went on the man. "As I was passing through this old house I saw, on one of the outer doors, an old-fashioned knocker. I am a collector of antiques, and I would very much like to have that. But I need help in getting it off. I do not intend to steal it, but if it is left here some tramp may destroy it, and that would be too bad. I intend to remove it, and then hunt up the owners of this place, and purchase it from them."

"It will be hard to discover who are the owners," replied Mark, "as the title is in dispute."

"So much the better for me. Will you help me remove the knocker? I will pay you for your time."

Mark hesitated. He did not like the man's manner, and there was a shifty, uneasy look about his eyes. Still he might be all right. But Mark did not like the idea of going into the old house with him alone. It might be safe, and, again, it might not. But the knocker was on an outside door. There could be no harm in helping him, as long as it was outside. The man saw the hesitation in the lad's manner.

"It will not take us long," the stranger said. "I want you to help me pry off the knocker, as I have no screw-driver to remove it. I will pay you well."

As he spoke he came nearer to Mark, and the lad noticed that the man's right hand was held behind his back. This struck Mark as rather suspicious. Suddenly he became aware of a peculiar odor in the air—a sweet, sickish odor. He started back in alarm, all his former suspicions aroused. The man seemed to leap toward him.

"Look out!" suddenly cried the fellow. "Look behind you!"

Involuntarily Mark turned. He saw nothing alarming. The next instant he felt himself grasped in the strong arms of the man, and a cloth that smelled strongly of the strange, sweetly sickish odor was pressed over the lad's face.

"Here! Stop! Let me go! Help! Help!" cried Mark. Then his voice died out. He felt weak and sick, and sank back, an inert mass in the man's arms.

"I guess I've got you this time," whispered the fellow, as he gazed down on Mark's white face. "I'll put you where you won't get away, either," and, picking up the youth, he carried him a prisoner into the deserted house.



CHAPTER VIII

JACK IS PUZZLED

Whistling merrily, with his mind as much on the big field of diamonds he expected to discover on the moon, as it was on anything else, Jack Darrow crossed over the meadows toward the telegraph office.

"By Jinks! It certainly will be great to fly through space once more," he mused. "Of course it isn't much of a trip, only a quarter of a million miles at most, but it will be a little outing for us, and then those diamonds!"

A trip of a quarter of a million miles only a little outing! But then what can be expected of lads who had gone to Mars and back again?

Jack lost no time in reaching the telegraph office, where he left the message to be sent, urging the operator to "rush" it, which that official promised to do.

"'Twon't be no great hardship on me, neither," he said with a cheerful grin, "seein' as how this is the only one I've had to send to-day. I'll get it right off for you, Jack."

Jack meant to hurry back, but, just as he was turning out of the main village street, to cut across lots, and join Mark at the place agreed upon, Jack saw two dogs fighting. It was with the best intentions in the world that he ran toward them, for he wanted to separate them. However a man was ahead of him, and soon had the two beasts apart. But Jack lingered several moments to see if there would be a renewal of the hostilities. There wasn't, and he hurried on. In a short time he was within sight of the barn, where his chum had agreed to meet him.

"Mark!" cried Jack, when he came within hailing distance.

There was no response.

"Maybe he's hiding to fool me," thought the lad, "I'll give him another call."

Neither was there a reply to this shout, and Jack, with a vague feeling of fear in his heart, hurried forward, climbed the fence that separated the field from the highway, and fairly ran toward the barn.

A glance sufficed to show that Mark was not in sight, and, thinking that his chum might be on the other side, Jack went around the structure.

"Oh, you Mark!" he called. "I'm back! Let's get a move on and go to the old house."

Silence was the only answer.

"That's queer," murmured Jack, when he had made a circuit of the place, and had seen no sight of his friend. "I wonder if anything could have happened to him? Perhaps he went inside, and has fallen down the hay mow. I'll take a look."

He made a thorough inspection of the ramshackle old structure, but there was no evidence that Mark had entered it, and Jack was soon quite assured that no harm had befallen his friend in there. Then a sudden thought came to him.

"Why, of course!" he exclaimed aloud. "I should have thought of that before. Mark got tired of waiting, and went on to the Preakness house. I might have known. I'll go on and catch up to him there."

Jack had reasoned correctly, but he could not know, what had taken place with only the old, grim, deserted mansion for a witness. With a lighter heart he set off down the road.

It did not take him long, at the pace he kept up, to come within sight of the old gateway, with the creeper twining over the pillars. Then he caught a glimpse of the house, and he at once slackened his footsteps.

"No use rushing into this thing," he reasoned in a whisper. "Mark may be in hiding, taking an observation of the mysterious man, and I don't want to spoil it, by butting in. Guess I'll lie low for a while, and see what develops."

Crouching down beside some bushes that lined the roadway Jack looked toward the silent, tumbled-down house and waited. All was still. Occasionally a shutter flapped in the wind, the hinges creaking dismally, or some of the loose window-panes rattled as the sash was blown to and fro. It was not a pleasant aspect, and as the afternoon was waning, and the sun was going down, while a cool wind sprang up, Jack was anything but comfortable in his place of observation.

And the one objection to it was that there was nothing to observe. Not a sign of life was to be seen about the place, and the broken windows, like so many unblinking eyes, stared out on the fields and road.

"Oh pshaw!" exclaimed Jack at length, "I'm not going to sit here this way! I'm going up and take a look. It can't bite me, and if that man's in there I can give him some sort of a talk that will make it look all right. I'm going closer. Maybe Mark's inside there, waiting for me, though it's queer why he didn't keep his agreement and wait for me at the barn. Well, here goes."

Though he spoke bravely, it was not without a little feeling of apprehension that Jack started toward the old mansion. He kept a close watch for the advent of any person or persons who might be in the house, but, when he reached the front porch, and had seen no one, he felt more at ease.

"Hello, Mark!" he cried boldly. "Are you inside?"

He paused for an answer. None came.

"This is getting rather strange," murmured Jack, who was now quite puzzled as to what to make of the whole matter. "Mark must be here, yet why doesn't he answer me? Oh, you Mark!" he shouted at the top of his voice.

There was only silence, and, after waiting a few moments Jack made up his mind that the best plan would be to enter the house and look around.

He made a hasty search through the lower rooms, but saw no sign of Mark. It was the same upstairs, and on the third floor there was no evidence of his chum. Jack called again, but got no reply.

"The garret next, and then the cellar," he told himself, and these two places, darker and more dismal than any other parts of the old mansion, were soon explored.

"Well, if Mark came here he's not here now," thought Jack, "and there's no use in my staying any longer. Maybe something happened that he had to go back home. Perhaps he's trailing the man. We should have made up some plan to be followed in case anything like that happened."

Deciding that the best thing he could do would be to go back home Jack came out of the old house. As he did so he gave a final call:

"Mark! Oh, you Mark! Are you anywhere about?"

What was that? Was it an answer, or merely the echo of his own voice? Jack started, and then, as he heard another sound, he said:

"Only the wind squeaking a shutter. Mark isn't here."

If Jack had only known!

Through the quickly-gathering darkness Jack turned his steps toward home. On the way along the country road he kept a sharp lookout for any sign of his chum, and, also, he looked to see if he could catch a glimpse of any person who might answer the description of the man they suspected of tampering with the Cardite motor.

But the road was deserted, save for an occasional farmer urging his horses along, that be might the more quickly get home to supper.

"It's mighty strange," mused Jack, as he kept on. "I don't think Mark did just right, and yet, perhaps, when it's all explained, he may have good reasons for what he did. Maybe I'm wrong to worry about him, and, just as likely as not, he's safe home, wondering what kept me. But he might have known that I'd come back to the barn where I said I'd meet him. Of course that dog-fight delayed me a little, but not much."

It was quite dark when Jack reached the house where he and his chum lived with the two professors. There was a cheerful light glowing from many windows, and Jack also noticed an illumination in the shed where the projectile was housed.

"Guess they're working on it, to get it in shape for the trip, sooner than they expected," he mused.

Jack was met at the door by Washington White.

"Hello, Wash!" greeted the lad.

"Good land a' massy! Where hab yo' been transmigatorying yo'se'f during de period when the conglomeration of carbohydrates and protoids hab been projected on to de interplanetary plane ob de rectangle?"

"Do you mean where have I been while supper was getting ready?" asked Jack.

"Dat's 'zackly what I means, Massa Jack."

"Then why don't you say it?"

"I done did. Dat's what I done. Supper's cold. But where am Massa Mark?"

"What! Isn't Mark home?" cried Jack, starting back in alarm.

"No, Massa Jack, we ain't seed him sence yo' two went off togedder. Where yo' all been?"

"Mark not home!" gasped Mark. "Where is Professor Henderson, Wash? I must speak to him at once."

"He am out in de shed wif Massa Roumann."

With fear in his heart Jack dashed out toward the big shed.

"Ain't yo' goin' t' hab some supper?" called Washington.

"I don't want any supper—yet," flung back Jack over his shoulder.



CHAPTER IX

A DARING PLOT

Mark Sampson lay an inert mass in the arms of the man who had attacked him. Through the sagging door of the old, deserted house the captive lad was carried, and up creaking stairs.

"I guess no one saw me," whispered the man. "I'm safe, so far, and I can work my scheme to perfection. Everything turned out well for me. I was just wondering how I could get this youth in my power, and he fairly walked into my hands! Now to keep him safe until I can take his place in the projectile, and have my revenge. I have waited a long time for it, but it has come at last!"

Pausing at the head of the creaking stairs the man looked behind him, to make sure that he was not being followed, but not a sound broke the stillness of the old house, save the rattle and bang of the ruined shutters.

"I'm safe! Safe!" exulted the man, with a cruel chuckle. "Now to bind him, and hide him in the secret chamber."

He laid Mark down on a pile of bagging in a corner of a room at the head of the stairs. Then, still glancing behind him, as if fearful of being observed, the man walked over to a mantlepiece, fumbled about a bit of carving that adorned the centre, and pressed on a certain spot. A moment later the mantle seemed to swing out, and there was revealed a secret room, the existence of which would never have been suspected by the casual observer.

Taking some of the bags from the pile where the unconscious lad was, the man made a rude bed in the secret room. Then he carried Mark in, and placed him in a fairly comfortable position, first taking the precaution, however, of binding his hands and feet.

"There," whispered the man, when he had finished, "I guess you'll not get away in a hurry. Now I'll wait until dark, and then I'll give you something to eat, for I don't want you to starve. But I must keep in hiding, for, very likely, there'll be a search made for him. Guess I'd better stay here, and see what happens," and the mysterious man pressed the spring that sent the mantle back into place again, hiding all traces of the secret room.

"It's a good thing I stumbled upon this hiding place," he said to himself. "It couldn't be better for what I want. Now to see what happens next."

He did not have long to wait, for in a short time Jack, as we have seen, appeared on the scene, and began his search. At the sound of his voice, calling for Mark, the man started in his hiding place, and glanced uneasily at Mark.

"He may hear, and wake up," he whispered.

Jack came upstairs in the deserted house, and continued his search there, calling from time to time. He gave one loud shout at the head of the stairs, and the very thing that the man feared would happen came to pass.

The effect of the drug having worn off, Mark stirred uneasily, and started up. He heard Jack's cry, and uttered a half-articulate answer. In an instant the man was at his side, and had quickly gagged him. This had the further effect of awakening the unfortunate lad; and he struggled to loosen his bonds, but they were too strongly tied. He endeavored to answer Jack, but only a meaningless mumble resulted, for the gag was effective.

"All you have to do is to keep quiet," urged the man, as he knelt beside Mark in the darkness. "As soon as your chum goes, I'll take that thing out of your mouth, and give you something to eat."

Jack's voice died away, and presently, as the ears of the man told him, the boy left the old house. Waiting some time, to make sure that he would not return, the man removed the knot of rags from Mark's mouth, and slightly loosened his bonds, first warning him, however, that if he attempted to escape he would be harshly dealt with.

"But what right have you to keep me here?" demanded the youth. "Who are you, and what have I done to you, that you should treat me this way? Are you crazy? Don't you know that you are liable to arrest for this?"

"No one can arrest me," boasted the fellow.

"But why have you made me a prisoner?" demanded Mark.

"For reasons of my own. You'll see very soon."

"But what have I done to you?" persisted the lad. "I never saw you before, that I know of, unless you are the man who sent me the note, and who ran when my chum and I came to the bridge to meet you."

"I'm the man," was the answer, with a chuckle.

"Then you must be the one who tried to wreck our projectile," went on Mark.

"Yes, I did that, and now I am sorry for it, for I have thought of a much better scheme for getting even, and having my revenge on you."

"But why do you want to be revenged on us?"

"Because of what you have done!" and the man's voice took on an ugly tone.

"But what did we do?" begged Mark.

"You'll know soon enough," was the answer, with a cunning laugh, and then Mark was sure he had to deal with a lunatic. He ceased his struggles to loosen the bonds, and resolved to meet cunning with cunning. He would bide his time.

"Will you promise to be quiet, and not kick up a fuss if I get you something to eat?" asked the man.

"Yes; but I'd rather have a drink of water first. I feel sick."

"Very well, you shall have some water. I'll have to go out and get it, but I must first blindfold you, so that you will not discover the secret of this room."

Mark could not help himself, for he was bound, and when the man had tied a handkerchief over his eyes, Mark heard his captor moving about.

Next there came a sound as of some heavy body, or object, being pushed across the room. Mark felt a draught of wind on his face, but it ceased instantly, and he knew that he was alone. He tried to work the bandage from over his eyes, and he endeavored to loosen his bonds, for he did not consider that this violated his promise. But it was of no effect.

Presently he heard the moving, shoving sound again, and once more felt the wind on his face. Then he heard the voice of his captor speaking.

"Here is food and drink. I'm going to untie your hands so you can eat, but mind, no fighting, for I'm a desperate man, and I won't stand any nonsense!"

He fumbled about the bonds, and soon Mark was free to stand up and use his hands. The bandage was taken from his eyes, and he was able to peer about his prison by the light of a candle which his captor had brought.

Mark's first glance was at the man. He was the same one who had emerged from the house to attack and drug him, but as for recognizing in him the person who had been at the bridge, this was impossible. As far as Mark could tell he had never seen the man before, nor did he answer the description given by Dick Johnson.

There was little danger that Mark would attempt violence. He was too weak, and his jailer seemed a powerful fellow. Then, too, the lad felt ill from the effects of the drug.

"Drink some water, and eat a bit, and you'll feel better," urged the man, which advice Mark followed, though, his appetite was not of the best, and he was much worried as to what his friends would think about his strange disappearance.

"What do you intend to do with me?" asked Mark, when he felt a little better from the effects of the food and drink. The man had sat on an old soap box, and watched his captive while he ate.

"Do with you? Why, I'm going to keep you here until your friends have left in the projectile," was the answer.

"But why don't you want me to go with them?"

"Oh, I have my reasons. You'll find out soon enough. You can't go, that's all."

"But why do you take such an interest in me? Why didn't you capture my chum Jack, too, while you were about it?"

"Two reasons. One was that Jack wouldn't answer my purpose, and the other was that I didn't have a chance to get him. You walked right into my trap, just when I was doing my best to think of another plan to get hold of you, since my first one failed."

"But what is your purpose?" insisted the lad. "What do you want with me?" He thought perhaps if he questioned the man closely enough he might discover something that would give him a clew, or might aid him to escape.

"You'll learn soon enough," was the answer.

"Will you tell me your name?" asked Marie quietly.

"No—why should I?" was the quick reply. "If I told you who I was you would at once know why I have made you a captive here. No; you shall hear all in good time, but that will not be until I am ready.

"Now," went on his captor, after a period of silence, "I shall have to bind and blindfold you again."

"Why?" asked Mark, in some alarm.

"Because I don't want you to see how I get in and out of this room, and that's the only way I can guard my secret. Though if you promise not to remove the bandage from your eyes within five minutes from the time I leave you, I will not have to tie your hands and feet. After I am gone you may take the handkerchief off, but when you hear me rap on the wall, ready to come back again, you must once more blindfold yourself. Otherwise I shall have to tie you up."

Mark considered a moment. It was not pleasant to be tied with the cruel ropes, and he felt that in time he could penetrate the mystery of how the room opened, even if he did not see his jailer enter and leave.

"I promise," he said finally.

"That's good. It simplifies matters. Now you can blindfold yourself, and I trust to your honor. You may remove the bandage in five minutes, but when you hear me knock, you must replace it until I am in the apartment. Then you can take it off again."

There was little choice but to obey, and Mark tied the handkerchief over his eyes. He listened intently, heard the man moving about the room, felt the wind on his cheeks, and then came silence.

He waited until he thought five minutes had passed, and then took off the bandage. The candle was burning where the man had set it, but the fellow himself was gone. He had taken with him the broken dishes, and remains of the food Mark had not eaten. The glass and a pitcher of water stood on a broken table, and Mark took a big drink.

"Now to see if I can't get out of this place," he murmured to himself.

Mark had invented many pieces of apparatus, and he was considered a good mechanician. Consequently he went about his task in a systematic manner. He examined the walls carefully by the candle, which he carried in his hand, but no opening was apparent.

"Of course, there must be some secret spring to press," said the lad. "That's how he gets in and out. A section of the wall moves, but where it is I can't see. It will take time. I must look at every inch."

He was in the midst of his investigations when there sounded on the wall back of him three raps.

"Ha! At least, that tells me where the opening is," thought the lad. "It's on that side, but now I have to put that blamed bandage on. Well, I may be able to escape yet."

True to his promise, he blindfolded himself well, and presently he heard a noise, felt a draught of air, and he knew his captor was in the room.

"You can now take off the handkerchief," said the man. "I have brought you some more bags for bed clothing. It isn't much, but it is all I have. They will keep you warm tonight."

"Are you going to imprison me over night?" asked Mark.

"Yes, and I'll stay here with you. No one can find us here. The secret room is well hidden. But first I have another matter that needs attention. I am going to ask you a question."

"What?" asked the captive, wondering what strange request the mentally unbalanced man would make now.

The man leaned forward and whispered something in Mark's ear, as if he was afraid the very walls would hear.

"I'll not do it!" cried the youth. "I'll never aid you to deceive my friends, for that is your object. I'll never do it!"

"Then I shall have to use force," was the determined response. "You may take your choice!"

Poor Mark did not know what to do, yet there was little he could choose between. The man had him in his power, yet the lad was terribly afraid of the result of the daring scheme which he knew was in the mind of the lunatic, for such he believed the man to be.

"Will you not give up this plan?" begged Mark. "I know Professor Henderson will pay you any sum in reason to let me go. You can become a rich man."

"I don't want riches—I want revenge!" exclaimed the man. And he glared at Mark, while throughout the dismal, deserted house there sounded the rattle and bang of the flapping shutters.



CHAPTER X

MARK'S STRANGE ACTIONS

Jack Darrow fairly burst into the big shed where the two scientists were at work over the ruined motor. They looked up at his excitable entrance, and Mr. Henderson called out:

"Why, Jack, what's the matter?"

"Quite a lot, I'm afraid," answered the lad, and there was that in his voice which alarmed the professors.

"What do you mean?" inquired Mr. Roumann, laying aside some of the damaged motor plates.

"Mark's gone!" gasped Jack.

"Gone! Where?" exclaimed Mr. Henderson.

"I don't know, but he went to the deserted house, where we thought the mysterious man was hiding, and since then I can't find him."

Then the frightened lad proceeded to explain what he and Mark had undertaken, and the outcome of it; how his chum had failed to meet him at the rendezvous, and how Jack had searched through the old house without result.

"There's but one thing to do," declared Professor Henderson, when he had listened to the story. "We must go back there and make a more thorough search."

"What—to-night?" exclaimed the German.

"Surely. Why not? We can't leave Mark there all alone. He may be hurt, or in trouble."

"That's what I think," said Jack. "I'll tell Washington and Andy, and we'll go back and hunt for him. Poor Mark! If he had only waited for me, perhaps this would never have happened, and if I hadn't stopped at the dog-fight maybe Mark would have waited for me. Well, it's too late to worry about that now. The thing is to find him; and I guess we can."

Jack would not stop longer than to snatch a hasty bite of supper before he joined the searching party. Washington and he carried lanterns, while Andy Sudds had his trusty rifle, and the two professors brought up in the rear, armed with stout clubs, for Jack's account of the affair made them think that perhaps they might have to deal with a violent man.

"Hadn't you better notify the police?" suggested Andy. "A couple of constables would be some help."

"Not very much," declared Jack. "Besides, there are only two in Bayside, and it's hard to locate either one when you want them. I guess we can manage alone."

"Yes, I would rather not notify the police if it can be avoided," said Professor Henderson.

The searching party hurried along the country highway, which was now deserted, as it was quite dark. Their lanterns flashed from side to side, but they had no hope of getting any trace of Mark until they came to the old barn, at least, though Jack wished several times that he might meet his chum running toward them along the road.

They reached the barn in due course, and while Washington, Jack and Andy began a search of it, the two scientists went up to the house of the man who owned it and enlisted his aid. They asked him if he had seen Mark around that afternoon, but the farmer had not.

"But me an' my hired man'll come out and help you hunt through the barn," he said. "I remember once, when I was a lad, that my brother fell off the hay mow and lay unconscious in a manger for five hours before we found him. Maybe that's what's happened to this young man," suggested Mr. Hampton, which was the farmer's name.

"I looked around pretty well this afternoon," explained Jack, when the farmer and his man had reached the barn, "but, of course, I didn't know all the nooks and corners."

A thorough search of the structure, however, failed to reveal the presence of Mark, and then the farmer volunteered to accompany the party on to the old Preakness house. His offer was received with thanks, and, bringing two more lanterns with them, Mr. Hampton and his man added considerable to the illumination.

They went through the old mansion from garret to cellar, and called repeatedly, but there was no answer. And good reason, for in the secret room, with his captive, the mysterious man heard the first approach of the searching party; and he quickly bound Mark and gagged him, so that he could not answer.

There was nothing to do but to leave, and it was with sad hearts that Jack and his friends departed, their search having been unavailing. They turned toward home, which they reached quite late, but found nothing disturbed.

No one in Professor Henderson's house slept much that night, and in the morning pale and wan faces looked at each other, all asking the same question: "Where is Mark?"

But no one could answer.

They talked over the matter, and decided that Jack, with Andy and Washington, should form a searching party to scour the surrounding country. The two scientists were too old for such work, and, as the aid of the police was not desired, it was felt that the three could do all that was necessary.

Accordingly, while Professor Henderson and his German friend went to work on the damaged motor, which did not need as much repairing as at first was thought to put it in working shape again, Jack and the two men started off to hunt for Mark.

They were gone all that day, returning very much discouraged at dusk, saying that they could get no trace of him.

"I don't see where he can be!" exclaimed Jack desperately, for, though the two lads were not related, they had been friends so long, and had shared so many pleasures and dangers together, that they were like brothers. "You won't start for the moon until you find him, will you, Professor?" asked Jack.

"No, indeed; though we could start to-morrow if he was here," replied the aged scientist. "The special tools came to-day, and the motor has been repaired. We have tested it, and the Cardite power works even better than did the Etherium apparatus."

"Then we can start as soon as Mark is found?" asked Andy Sudds.

"Yes, for everything has been put inside the projectile, and all that remains is to haul it out of the shed, point it at the moon, and start the motor."

"Then I guess I'll give my gun a final cleaning, and get ready. There may be good hunting on the moon," said the old hunter.

Jack was tired from his long tramp that day, searching for his missing chum, but before he went to bed he wanted to go out and take a look at the big projectile, which was now ready to start for the moon.

As he turned around the corner of the immense shed to enter the door, he was startled by seeing a figure coming toward him. Jack started, rubbed his eyes, and peered again.

"Is it possible? Can I be mistaken?" he whispered.

The figure came nearer. Jack, who had come to a halt, broke into a run.

"Mark! Mark!" he cried joyously. "Oh, you've come back! Where have you been?"

Jack was about to clasp his chum in his arms when he saw that Mark's arm was in a sling, and that his face was all bandaged up, so that scarcely any of his features showed. Had it not been for the clothes, and a certain stoutness of which Mark never could seem to get rid, Jack would scarcely have known his friend.

"Why, Mark, what happened?" cried Jack. "Have you met with an accident? Where have you been? In a hospital? What became of you? Why didn't you wait for me?"

"I can't answer all those questions at once," was the reply, and Jack thought Mark's voice was curiously muffled and hoarse, entirely unlike his usual tones. But he ascribed that to the bandages around the mouth.

"Well, answer one at a time then," said Jack, and there was an undefinable, strange air about his chum which cooled Jack's first impulse of gladness. "Whatever happened to you, Mark? Are you hurt?"

"I was—yes," came the reply, in short, jerky tones. "I had an accident, and I've been in a hospital. That's why I couldn't send you word. But I'm all right now. When does the projectile start?"

"To-morrow, now that you're here. But tell me more about it. Where were you hurt?"

"On my head and arm."

"No; I mean where did the accident occur?"

"Oh, in the old house where I went to—to look for that man."

"Did you find him?" asked Jack eagerly.

"No. He's not there now."

"Well, never mind. We won't bother about him. Come on to the house. My, but I'm glad to see you again! And so will the others be."

In his enthusiasm at seeing his chum again Jack wanted to hug him. He approached Mark, but the latter cried out:

"Look out! Don't come too close!"

"Why not? Have you caught some disease?"

"No, but you might hurt my broken arm!"

"Oh, is it broken? That's tough luck. Did you fall?"

"Yes—in the old house. I fell down stairs."

"And your head is all bandaged up, too," went on Jack, trying to peer into his friend's face through the roll of bandages.

"Look out! Don't come too near!" again warned the other. "You might jostle against me, and knock off some of the bandages."

"Did you lose some of your teeth, the reason your voice sounds so funny?" asked Jack.

"Yes, I did knock out a few when I tumbled. But don't bother about me. I'll be all right soon. Let's go in the house. I want to go to bed."

"But they'll all want to see you, and hear about the accident, Mark," insisted Jack. "My, but we've been all worked up about you. How did you happen to be taken to a hospital?"

"A farmer came along, and I hailed him. Then I lost consciousness, and couldn't let you know where I was. But never mind the details. I'm anxious to get started on the trip to the moon. Couldn't we start to-night?"

"I don't believe so. You need rest. But come on in the house." Then Jack hurried on ahead, calling: "Mark's found! Mark is back!"