Johnny’s thoughts were cut short by a hand lightly laid on his shoulder.
“Thought I’d find you here.” It was his employer. “Some things in the factory I want to show you when the men are gone. They’re about out now. I’ll just wait here. Don’t let me disturb you.”
But Johnny had been disturbed; his eyes for the moment had been drawn from that passing string of men and the electro-magnet. As he again focused his eyes on the crack, he gave an involuntary start. Clinging to the face of the electro-magnet as if glued there, was an oblong paper box—a lunch-box. And the man who owned it? He had passed on out of sight without any apparent attempt to regain possession of his property.
“Rotten luck!” Johnny’s lips framed the words but did not say them. The trap had worked. There was iron or steel in that box; that was why the powerful electro-magnet had drawn it to itself. He had recovered the property, but his man had escaped. The precious steel was safe. That much was good. He heaved a sigh of relief; watched the last workman march by, touched the switch, saw the box drop from the magnet as the current was shut off, then turned toward the door.
At this point a doubt came to his mind. What if the metal in the box proved to be some other metal than the precious steel? He had been about to display his catch in triumph. He decided to make sure first, and so merely said: “In just a moment I’ll be ready.”
Stepping outside, he secured possession of the mysterious lunch-box and, carrying it as if it were dynamite, again entered the cubby-hole and said cheerfully: “All right; I’m ready now.”
As they walked slowly back into the factory Johnny’s eyes turned first to the right, then to the left. For the time the baffling mysteries of the hour were forgotten, and for the hundredth time he was lost in admiration of this marvel of modern industry, a vast manufacturing plant. Here they passed through the forge-room where, by the dull light of dying fires, one might see trip-hammers, looming like giants, resting from their labors. Now again they passed through a sand-strewn room where crater-like heaps were smoking—the foundry. And now they emerged into the assembly-room, where were automobiles partly put together, and further down, airplanes poised like giant birds ready for flight.
“The things I am to show you to-night”—the voice of his employer roused him from the spell which the place had put upon him—“are secrets, secrets known only to myself and two other men. This factory was rebuilt and enlarged during the World War. Our entire output was then being taken by the Government. In those days every precaution was necessary. Spies of the enemy were all about us and in our very midst, seeking out our most valuable secrets, ready to destroy our plants and so cripple our army. It was such a time as this that I had installed in this plant the contrivances which I am about to show you and which may, perhaps, be of assistance to you. Your work from now on will be done at night. You slept this afternoon as I instructed?”
“Yes.”
“Good. Then you will be all right for tonight.”