It was connected to the sliding panel by a neatly fashioned contrivance that was to set to press the trigger of the gun every time the slide came up.
Cardona removed the gun and brought it out. As he stepped away, he released pressure on the sides of the radiator, and they swung back to their original position.
A sharp click told that the sections had automatically locked.
“Five chambers,” remarked Cardona. “Wonder where the old guy dug up this rod. A .32. Hm-m-m. Four cartridges used.
“One for Harshaw. One for Max Parker. One just now. Wonder when the other was fired.”
“That hardly matters,” said Biscayne. “Let’s look in that compartment again.”
He pulled the knob of the radiator. This time, Cardona opened the metal sections with impunity, for the menace had been removed.
He discovered a small stack of letters and some papers. Also another object, which Cardona seized with a sharp exclamation.
It was a cigarette box, bearing the name, “Istanbul.”
“The brand that Glenn smoked!” proclaimed Cardona.