In the same moment, with all his waning frail strength, Clive lurched forward and brought his right fist sharply down on Osmun’s wrist.

The pistol flew from the killer’s jarred grasp and clattered to the floor. By the time it touched ground Clive had swooped upon it and snatched it up.

Osmun, discovering the trick whereby he had been disarmed, grabbed at the fallen pistol at practically the same time. But he was a fraction of a second late.

He found himself blinking at the leveled black muzzle of his own revolver in the hand of the brother he had been preparing to slay.

Osmun recoiled in dread, springing backward against the laboratory wall, directly beneath a shelf of retorts and carboys.

Then his terror-haunted eyes glinted as they rested on his brother.

Clive’s sudden exertion and the shock of excitement had been too much for his enfeebled condition of nerve and of body. Something seemed to snap in his brain, and the taut spring that controlled his fragile body seemed to snap with it.

The pistol wabbled in his nerveless grasp. He swayed backward, his eyes half shut. He was on the brink of absolute collapse.

Osmun Creede gathered himself for a leap upon the half-swooning man.

With a final vestige of perception Clive noted this. Summoning all he could of his lost strength, he sought to save his newly imperiled life by leveling the pistol before it should be too late and by pulling the trigger.