Tom Swift opened the door of the improvised rifle gallery and looked out. By the light of a full moon, which shone down from a cloudless sky, he saw a man standing at the portal. The man's face was distorted with rage, and he shook his fist at the young inventor.

"What do you mean by shooting at me?" he demanded. "What do you mean, I say? The idea of scaring honest folks out of their wits, and making 'em think the end of the world has come! What do you mean by it? Why don't you answer me? I say, Tom Swift, why don't you answer me?"

"Because you don't give me a chance, Mr. Moker," replied our hero.

"I want to know why you shot at me? I demand to know!" and Mr. Moker, who was a sort of miserly town character, living all alone in a small house, just beyond Tom's home, again shook his fist almost in the lad's face. "Why don't you tell me? Why don't you tell me?" he shouted.

"I will, if you give me a chance!" fairly exploded Tom. "If you can be cool for five minutes, and come inside and tell me what happened I'll be glad to answer any of your questions, Mr. Moker. I didn't shoot at you."

"Yes, you did! You tried to shoot a hole through me!"

"Tell me about it?" suggested Tom, as the excited man calmed down somewhat. "Are you hurt?"

"No, but it isn't your fault that I'm not. You tried hard enough to hurt me. Here I am, sitting at my table reading, and, all at once something goes through the side of the house, whizzes past my ear, makes my hair fairly stand up on end, and goes outside the other side of the house. What kind of bullets do you use, Tom Swift? that's what I want to know. They went through the side of my house, and never left a mark. I demand to know what kind they are."

"I'll tell you, if you'll only give me a chance," went on Tom wearily. "How do you know it was me shooting?"

"How do I know? Why, doesn't the end of this shooting gallery of yours point right at my house? Of course it does; you can't deny it!"

Tom did not attempt to, and Mr. Moker went on:

"Now what do you mean by it?"

"If any of the bullets from my electric gun went near you, it was a mistake, and I'm sorry for it," said Tom.

"Well, they did, all right," declared the excited man. "They went right past my ear."

"I don't see how they could," declared Tom. "I was trying my new electric rifle, but I had the limit set for two hundred feet, the length of the gallery. That is, the electrical discharge couldn't go beyond that distance."

"I don't know what it was, but it went through the side of my house all the same," insisted Mr. Moker. "It didn't make a hole, but it scorched the wall paper a little."

"I don't see how it could," declared Tom. "It couldn't possibly have gone over two hundred feet with the gage set for that distance." He paused suddenly, and hurried over to where he had placed his gun. Catching up the weapon he looked at the gage dial. Then he uttered an exclamation.

"I'm sorry to admit that you are right, Mr. Moker!" he said finally. "I made a mistake. The gage is set for a thousand feet instead of two hundred. I forgot to change it. The charge, after passing through the steel plate, and the scarecrow figure, destroying the latter, went on, and shot through the side of your house."

"Ha! I knew you were trying to shoot me!" exclaimed the still angry man. "I'll have the law on you for this!"

"Oh, that's all nonsense!" broke in Ned Newton "Everybody knows Tom Smith wouldn't try to shoot you, or any one else, Mr. Moker."

"Then why did he shoot at me?"

"That was a mistake," explained Tom, "and I apologize to you for it."

"Humph! A lot of good that would do me, if I'd been killed!" muttered the miser. "I'm going to sue you for this. You might have put me in my grave."

"Impossible!" exclaimed Tom.

"Why impossible?" demanded the visitor.

"Because I had so set the rifle that almost the entire force of the electrical bullet was expended in blowing apart the scarecrow figure I made for a test," explained Tom. "All that passed through your house was a small charge, and, if it had hit you there would have been no more than a little shock, such as you would feel in taking hold of an electric battery."

"How do I know this?" asked the man cunningly. "You say so, but for all I know you may have wanted to kill me."

"Why?" asked Tom, trying not to laugh.

"Oh, so you might get some of my money. Of course I ain't got none," the miser went on quickly, "but folks thinks I've got a lot, and I have to be on the lookout all the while, or they'd murder me for it."

"I wouldn't," declared the young inventor. "It was a mistake. Only part of the spent charge passed near you. Why, if it had been a powerful charge you would never have been able to come over here. I set the main charge to go off inside the scarecrow, and it did so, as you can see by looking at what's left of it," and he pointed to the pile of clothes and rags.

"How do I know this?" insisted the miser with a leer at the two lads.

"Because if the charge had gone off either before or after it passed through the figure, it would not have caused such havoc of the cloth and straw," explained Tom. "First the charge would have destroyed the steel plate, which it passed through without even denting it. Why, look here, I will now fire the rifle at short range, and set it to destroy the plate. See what happens."

He quickly adjusted the weapon, and aimed it at the plate, which, had again been set up on the range. This time Tom was careful to set the gage so that even a small part of the spent. charge would not go outside the gallery.

The young inventor pressed the button, and instantly the heavy steel plate was bent, torn and twisted as though a small sized cannon ball had gone through it.

"That's what the rifle will do at short range," said Tom. "Don't worry, Mr. Moker, you didn't have a narrow escape. You were in no danger at all, though I apologize for the fright I caused you."

"Humph! That's an easy way to get out of it!" exclaimed the miser. "I believe I could sue you for damages, anyhow. Look at my scorched wall paper."

"Oh, I'll pay for that," said Tom quickly, for he did not wish to have trouble with the unpleasant man. "Will ten dollars be enough?" He knew that the whole room could be repapered for that, and he did not believe the wall-covering was sufficiently damaged for such work to be necessary.

"Well, if you'll make it twelve dollars, I won't say anything more about it," agreed the miser craftily, "though it's worth thirteen dollars, if it is a penny. Give me twelve dollars, Tom Swift, and I won't prosecute you."

"All right, twelve dollars it shall be," responded the young inventor, passing over the money, and glad to be rid of the unpleasant character.

"And after this, just fire that gun of yours the other way," suggested Mr. Moker as he went out, carefully folding the bills which Tom had handed him.

"Hum! that was rather queer," remarked Ned, after a pause.

"It sure was," agreed his chum. "This rifle will do more than I thought it would. I'll have to be more careful. I was sure I set the gage for two hundred feet. I'll have to invent some automatic attachment to prevent it being discharged when the gage is set wrong." Let us state here that Tom did this, and never had another accident.

"Well, does this end the test?" asked Ned.

"No, indeed. I want you to try it, while I look on," spoke Tom. "We haven't any more stuffed figures to fire at, but I'll set up some targets. Come on, try your luck at a shot."

"I'm afraid I might disturb Mr. Moker, or some of the neighbors."

"No danger. I've got it adjusted right now. Come on, see if you can shatter this steel target," and Tom set up a small one at the end of the range.

Then, having properly fixed the weapon, Tom handed it to his chum, and, taking his place in a protected part of the gallery, prepared to watch the effect of the shot.

"Let her go!" cried Tom, and Ned pressed the button.

The effect was wonderful. Though there was no noise, smoke nor flame, the steel plate seemed to crumple up, and collapse as if it had been melted in the fire. There was a jagged hole through the center, but some frail boards back of it were not even splintered.

"Good shot!" cried Tom enthusiastically. "I had the distance gage right that time."

"You sure did," agreed Ned. "The electric bullet stopped as soon as it did its work on the plate. What's next?"

"I'm going to try a difficult test," explained Tom. "You know I said the gun would shoot luminous charges?" "Yes."

"Well, I'm going to try that, now. I wish we had another image to shoot at, but I'll take a big dry-goods box, and make believe it's an elephant. Now, this is going to be a hard test, such as we'd meet with, if we were hunting in Africa. I want you to help me."

"What am I to do?" asked Ned.

"I want you to go outside," explained Tom, "set up a dry-goods box against the side of the little hill back of the shed, and not tell me where you put it. Then I'll go out, and, by means of the luminous charge, I'll locate the box, set the distance gage, and destroy it."

"Well, you can see it anyhow, in the moonlight," objected Ned.

"No, the moon is under a cloud now," explained Tom, looking out of a window. "It's quite dark, and will give me just the test I want for my new electric rifle."

"But won't it be dangerous, firing in the dark? Suppose you misjudge the distance, and the bullet, or charge, files off and hits some one?"

"It can't. I'll set the distance gage before I shoot. But if I should happen to make a mistake the charge will go into the side of the hill, and spend itself there. There is no danger. Go ahead, and set up the box, and then come and tell me. Mr. Jackson will help you."

Ned and the engineer left the gallery. As Tom had, said, it was very dark now, and if Tom could see in the night to hit a box some distance away, his weapon would be all that he claimed for it.

"This will do," said the engineer, as he pointed to a box, one of several piled up outside the shed. The two could hardly see to make their way along, carrying it to the foot of the hill, and they stumbled several times. But at last it was in position, and then Ned departed to call Tom, and have him try the difficult test--that of hitting an object in the dark.