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.

CHAPTER IV

BIG TUSKS WANTED

“Well, are you all ready for me?” asked the young inventor, as he took up his curious weapon, and followed Ned out into the yard.  It was so dark that they had fairly to stumble along.