“That shooter behind the radiator!” he exclaimed. “It wasn’t there just to keep people from finding a few papers and envelopes. That’s where the model is, I’ll bet!”
Eagerly, the detective pulled the knob of the radiator and opened the sections.
He realized again the efficiency of this trap. A man shot here would topple backward — falling, he would lose hold, and the radiator would close!
It had happened with Silas Harshaw. It had happened with Max Parker. But it could not happen now, since the clamped revolver had been removed.
Peering in the light of his torch, Cardona spied the flat bottom of the shallow hole inside the wall.
His fingers pried, and were rewarded. The bottom of the strong box swung upward. The glow of the flashlight spotted a square wooden box.
Dropping his light, Cardona drew the box out and set it in the middle of the floor. He lifted the lid.
Inside was a metal device, more than one foot square. It seemed strangely light as Cardona removed it from the box.
It had dials and knobs, with little posts for the attachment of wires.
It was the model of the remote-control machine — the invention of which had been the life work of Silas Harshaw!