"Maybe the Martians won't let you."

"Maybe not. I wish we could start to-morrow."

"Well, we can't. The Annihilator isn't near done. We will be at her for two weeks yet."

The boys were busy for some time fitting up the living-room.

They were in the midst of this occupation, and were conversing about the strange experiences in store for them, when Jack was startled by hearing a strange voice say:

"Say, don't you want some help building this airship?"

He looked up, to see a man standing near one of the entrances to the projectile--an entrance that would be closed when the Annihilator was finished. The man was a stranger, and from his appearance Jack judged that he was a mechanic.

"How'd you get in here?" asked Mark, for he knew it was against the rules for any stranger to enter the machine shop, much less approach the projectile.

"I walked," replied the man. "I saw the door open, and I heard hammering going on in here. I knew it was a machine shop, and as I'm a first cla.s.s machinist, out of work, I thought I'd apply for the job."

"How'd you get past the doorkeeper?" inquired Jack, for he knew that Andy Sudds was supposed to be on guard with his gun.

"He wasn't at the door," went on the man. "There was n.o.body there, so I walked in. Can't you give me a job on the airship?"

"How do you know it's an airship?" asked Jack.

"Oh, I know. I know lots of things," and the man winked one eye at the lad. "I built a balloon once."

"Did you?" asked Mark. He began to think perhaps the man might be able to aid them.

"Sure I did. I know about airships. I'll work for low wages, and I'll keep my mouth closed. Oh, I know what patents mean.

Say," he went on in a whisper, "you'd be surprised to know where I went in my balloon. I'll tell you," and he looked around as if to make sure no one was listening.

"Where did you go?" asked Jack.

"Up to the moon," was the surprising reply. "And, say, it's all a mistake about it being made of green cheese. It's green apples--that's what it's made of. I know, for I was there, and I ate some. They gave me an awful pain in my head, too," and the man pa.s.sed his hand across his brow. "A fearful pain," he went on.

Jack and Mark looked at each other. They did not understand the man's strange talk and actions.

"You don't believe me, do you?" the stranger asked. "Well, if you want a good machinist, hire me. I know all about airships and traveling through s.p.a.ce. Why, I once did a dance on the tail of a comet, only the comet got mad and shook me off. I'll show you how I danced."

He threw a somersault, lighted on his hands, and began to waltz about in the somewhat contracted s.p.a.ce of the living-room of the projectile. Then he set up a loud shout as he regained his feet.

"That's how!" he cried.

The boys were alarmed. The man was evidently crazy, or perhaps he might be doing this for effect, in order to disarm their suspicions, so that he could discover Mr. Roumann's secret.

They did not know what to do.

"Come on, we'll all have a dance!" cried the man. "My name is Axtell--Fred Axtell. I used to live on the moon--tra-la-la!"

His loud voice attracted the attention of Mr. Henderson, who was working at the far end of the shop. The professor ran toward the place where the strangely acting man was, the latter having now emerged from the ship, followed by the boys.

"Here we go! Off to the moon!" cried the man, and catching up a big hammer he began to pound on the sides of the Annihilator as if he would destroy the projectile.

CHAPTER X

WASHINGTON IS AFRAID

"Here! Here! Stop him! Grab that man!" cried Mr. Roumann, as he rushed toward Axtell, who was hammering away madly.

Jack and Mark started for the fellow.

"Keep away!" cried the machinist, swinging the sledge toward the boys. "I want to work on an airship, and I'm going to do it.

I'll make some dents in it, and then I'll straighten them out!

Whoop!"

Mr. Henderson hastened forward. He took in the situation at a glance.

"That man is insane!" the professor whispered to the German scientist. "Let me deal with him."

"Do something quickly," pleaded Mr. Roumann, "or he will damage the projectile."

"This is the way I work!" cried the insane man, and he brought down the hammer with great force on the rounded sides of the Annihilator. He made quite a dent in it.

"Stop him!" begged Mr. Ronan.

Mark and Jack had retreated out of reach of the big hammer, the professor and the German were consulting together, and in the door of the shop appeared Andy Sudds with his gun. He had gone away for a moment, in which interval the crazy machinist had appeared.

"Andy will scare him with his gun," whispered Jack to Mark.

Just then Mr. Henderson called out:

"If you want work, I can give it to you."

Axtell stopped his pounding of the projectile, laid his hammer down, and asked in a mild voice:

"Can you give me work now?"

"Of course," answered the professor, as if it was the most natural thing in the world to give work to insane persons. His calm manner and soothing words had a quieting effect on the lunatic. The glare died out of his eyes.

"Come with me," went on Mr. Henderson. "I have some work outside."

"What is it?" asked Axtell suspiciously.

"I want you to dig a hole so we can put this airship in it,"

whispered the professor. "Come outside."

He wanted to get the man out of the machine shop, where he could better deal with the fellow.