"Did that other man come aboard with you?" asked Jack. He referred to the tramp who had peered in the window of the professor's house.

"No. He's been elected King of France," was the answer. "He had to go over there to get his crown fitted on. I'm all alone here.

A few minutes more and I would have smashed that engine."

"I guess you would," responded Mr. Roumann. "Well, we'll take good care that you do not get loose again."

The bonds of the maniac were made more secure, and Washington White was told to keep, close watch over him.

It was the day after this occurrence, though Jack and Mark had not gotten over talking about it, that they were in the pilot house with Professor Henderson. The projectile was speeding along rapidly, and from calculations that had been made it was believed they would arrive at Mars in about two days.

"I'll be glad of it," said Jack. "I want a chance to stretch my legs."

"And grow lighter," added Mark. "You're fatter than ever since you began this trip."

"That's because I don't have any exercise. But I'll make up for it. I understand that on Mars one can jump twice as far as he can on the earth, due to the less dense atmosphere."

"Well, we'll soon see," said Mark.

Mr. Henderson suddenly bent over one of the indicators. He pressed a lever, turned a wheel, and then exclaimed:

"The Etherium motor has stopped working 'again! I wonder if the maniac is loose!"

"We'll see!" cried Jack, as he and Mark hurried toward the engine-room. They found Mr. Roumann there.

"The motor has stopped!" exclaimed Jack.

"I know it."

"Has there been an accident?"

"No."

"What's the matter, then?"

"We have completed our journey through the ether. The motor will only work in that."

"And that means--" began Mark.

"That we have reached the atmosphere of Mars!" exclaimed Mr.

Roumann in triumph.

CHAPTER XXI

MARS AT LAST

Antic.i.p.ating, as they had for some time past, such an announcement, it was none the less startling to the boys.

"Then we are really nearing Mars?" exclaimed Jack.

"Not only nearing it, but we will be there within twenty-four hours," answered the German scientist. "I was looking for this.

I expected the Etherium motor to stop as soon as it reached the atmosphere of the planet, and it has done so. We will not have to start it again until we make the return trip. I will now again put into operation the atmospheric motor, and we will see how it behaves. Kindly inform Mr. Henderson, so he will understand what is taking place."

Mark hastened to the pilot house with this message, and then returned to watch Mr. Roumann, the professor agreeing to remain at the steering wheel until relieved by his friend.

Mr. Roumann began adjusting the second motor. It had been kept in readiness for instant service, and did not require much attention.

"I don't see why we have to use it at all," said Jack.

"Why shouldn't we?" Mark wanted to know.

"Because if we are near Mars it ought to attract us, just as if we were near the earth. We ought to fall right into it."

"That is just the danger," commented Mr. Roumann. "We don't want to fall. We want our projectile under perfect control, and I can only attain that end by using the motor. Besides, we are not near enough to Mars to be attracted by its force of gravitation, even supposing it is the same as that of our earth. We might not be attracted at all, and if we did not use the motor we might float around the planet as if we were a moon. No, if we wish to reach Mars we must use the atmospheric motor."

A few minutes later it was started, and the Annihilator was once more speeding along, this time under new power, and not quite so fast. All on board the projectile found themselves antic.i.p.ating what they would see on the new and wonderful planet they were soon to visit.

"It hardly seems possible," murmured Jack, "that we have made such a journey--the longest on record."

"It will be more wonderful if we get back to earth," spoke Mark.

"Oh, I don't know," went on his chum. "We may like it so on Mars, that we'll want to stay. And there isn't any reason why we shouldn't, provided we find nice people there. We haven't many friends, Mark. Our best ones are right here with us. We could just as well stay as not."

"Yes, provided, as you say, that the Martians are nice people.

But you must remember that we're going to be strangers in a strange land."

"Well, one always treats strangers politely," declared Jack. "I guess we'll get along all right. Anyhow, I'm glad we're near there."

"So am I," declared Mr. Henderson. "I will be able to make some scientific observations, and, perhaps, write a book about them when I get back to earth. I might make some money out of it."

"You won't need to make money, if what I suspect is true," said Mr. Roumann.

"What is that?"

"Well, I can't go into details now, but I hope to secure something that will make our fortunes. There is only one thing I fear."

"What is that?"

"The Martians may prevent me taking any of it away. But I am not going to borrow trouble. Let us see how the motor is working."

They had all gone, with the exception of Andy and Washington, to the pilot house, and they now returned to the engine-room.

"Ha! That is rather strange!" exclaimed Mr. Roumann as he looked at the buzzing machinery.

"What's the matter?" asked Mark.