“I’m sorry,” he said evenly. “But I’ve got to do it. If I could see any other way out I’d let you go. But you’ve brought it on yourself. I can hide you in the cellar under here till night and then bury you with enough of the right chemicals to make it impossible to identify you if ever any one should blunder onto the grave. I’m sorry, Clive.” He spoke with no emotion at all. He felt no emotion. He was oddly calm in facing this one course open to him. Now Clive Creede had spent more than a year in war-scourged lands where human life was sacrificed daily in wholesale quantities and where death was as familiar a thing as was the sunlight. Like many another overseas veteran he had long ago lost the average man’s fear of a leveled firearm. Thus the spectacle of this pistol and of the coldly determined eyes behind it did not strike him with panic. It was a sight gruesomely familiar to him from long custom. And it did not scatter his wits. Rather did it quicken his processes of thought. “If you’re really set on murdering me, Oz,” he said, forcing his tired voice to a contemptuous drawl, “suppose you do the thing properly? For instance, why not avoid the electric chair by waiting till there are no witnesses?” As he spoke his eyes were fixed half-amusedly on the laboratory window directly behind his brother. He made a rapid little motion of one hand as if signaling to some one peering in at the window. It was an old trick--it had been old in the days when Shakespeare made use of it in depicting the murder of the Duke of Clarence. But it served. Most old tricks serve. That is why they are “old” tricks and not dead-and-forgotten tricks. Osmun spun halfway around instinctively to get a glimpse of the imaginary intruder who was spying through the window upon the fraternal scene. 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.