"Are you there, Tom?"
"Yes dad, is anything the matter?"
"No, but I thought I'd like to see what luck you have. Rad was saying you were going to have a test in the dark."
"I'm about ready for it," replied Tom. "I'm going to blow up a box that I can't see. You know how it's done, dad, for you helped me in perfecting the luminous charge, but it's going to be something of a novelty to the others. Here we go, now!"
Tom raised his rifle, and aimed it in the dark. Ned Newton, straining his eyes to see, was sure the young inventor was pointing the gun at least twenty feet to one side of where the box was located, but he said nothing, for from experiences in the past, he realized that Tom knew what he was doing.
There was a little clicking sound, as the youth moved some gear wheel on his gun. Then there came a faint crackling noise, like some distant wireless apparatus beginning to flash a message through space.
Suddenly a little ball of purplish light shot through the darkness and sped forward like some miniature meteor. It shed a curious illuminating glow all about, and the ground, and
