He wheeled and sent another charge of static electricity into the crevice back of him, then lunged out into the control room. It would be his own weapon against Krenski's, and a chance to gain the bottom of the shaft. Krenski--piled, charred heaps of the Petrolia around him, which had momentarily cleared the attack--was running across the control room. Like a seething wave, the foul Petrolia undulated from every crevice and hallway, coming in to fresh attack. The Russian, terror lending him speed, raced for the cage at the foot of the shaft that led to the surface. At the same time Asher ran out. Nearly a hundred feet apart, on opposite sides of the cavern, they stopped. Krenski turned his heavy weapon toward Asher at the same time Asher sent his own gun crackling and snapping out blue, fiery flame. Side-stepping, now crouching, now dodging to this side and that, they fought their strange duel. Asher's right arm was burned, his hair singed from his head, and his body jarred again and again as Krenski touched him. Krenski, groaning through gritted teeth, suffered burns all over his chest and left leg. As the Petrolia came on, and the lightning play of deadly electric charges continued, Asher made a discovery. He noticed that the rays, or charges, of the two guns, when they met in mid-air, caused blue flame, and that the charge went no farther. It did it again. The two charges met, crackled to explosion in the air. Krenski, too, noticed it, and he also noticed that the Petrolia were almost upon them again. Coming on in a wave that could not be hurled back. * * * * * He looked at Asher, and met the dare in Asher's eyes. Straight at each other, neither moving, they shot their static charges. Neither would move: it was a challenge from Asher that Krenski had to meet. One of them would have to die before the other would be able to gain the cage in the shaft. There could be no compromise, and only one man at a time could go surfaceward. If they continued to dodge and fight, the Petrolia would overwhelm them. Power against power, they fought it out. Asher's finger tightened on his trigger release until it seemed the skin would split; then he caused his hand to tremble just enough to make his electric charges cover the space in which Krenski's charges traveled. Hissing, spitting, flashing explosions, giving off sounds and light like big explosions of flash powder, the charges met. Asher tingled from head to foot, and thrilled to the very marvel of the thing. Two deadly beams of electricity, holding each other off!