Then, before the light had died away, they witnessed a curious sight. The heavy wooden box seemed to dissolve, to collapse and to crumple up like one of paper, and ere the last rays of the illuminating bullet faded, the watchers saw the splinters of wood fall back with a clatter in a little heap on the spot where the dry-goods case had been. A silence followed, and the darkness was all the blacker by contrast with the intense light. At length Tom spoke, and he could not keep from his voice a note of triumph. "Well, did I do it?" he asked. "You sure did!" exclaimed Ned heartily. "Fine!" cried Mr. Swift. "Golly! I wouldn't gib much fo' de hide ob any burglar what comed around heah!" muttered Eradicate Sampson. "Dat box am knocked clean into nuffiness, Massa Tom." "That's what I wanted to do," explained the lad. "And I guess this will end the test for tonight." "But I don't exactly understand it," spoke Ned, as they all moved toward the Swift home, Eradicate going to the stable to see how his mule was. "Do you have two kinds of bullets, Tom, one for night and one for the daytime?" "No," answered Tom, "there is only one kind of bullet, and, as I have said, that isn't a bullet at all. That is, you can't see it, or handle it, but you can feel it. Strictly speaking, it is a concentrated discharge of wireless electricity directed against a certain object. You can't see it any more than you can see a lightning bolt, though that is sometimes visible as a ball of fire. My electric rifle bullets are similar to a discharge of lightning, except that they are invisible." "But we saw the one just now," objected Ned. "No, you didn't see the bullet," said Tom. "You saw the illuminating flash which I send out just before I fire, to reveal the object I am to hit. That is another part of my rifle and is only used at night." "You see I shoot out a ball of electrical fire which will disclose the target, or the enemy at whom I am firing. As soon as that is discharged the rifle automatically gets ready to shoot the electric charge, and I have only to press the proper button, and the 'bullet,' as I call it, follows on the heels of the ball of light. Do you see?" "Perfectly," exclaimed Ned with a laugh. "What a gun that would be for hunting, since most all wild beasts come out only at night." "That was one object in making this invention," said Tom. "I only hope I get a chance to use it now." "I thought you were going to Africa after elephants," spoke Mr. Swift. "Well, I did think of it," admitted Tom, "but I haven't made any definite plans. But come into the house, Ned, and I'll show you more in detail how my rifle works." Thereupon the two chums spent some time going into the mysteries of the new weapon. Mr. Swift and Mr. Jackson were also much interested, for, though they had seen the gun previously and had helped Tom perfect it, they had not yet tired of discussing its merits.