Something was tapping on his helmet. Bormon opened his eyes, and light was trickling down between the chunks of ore. No longer was there any scraping vibrations. Something, metallic, snakelike, was being pressed into his hand.
And then Bormon remembered. The oxygen tube! With a final rallying of forces only partly physical, he managed to stab the tube over the intake of his tank. The automatic valve clicked and a stream of pure delight swept into his lungs!
For a time he lay there, his body trembling with the exquisite torture of vitality reawakening, slowly closing the helmet-valve to balance the increase of pressure in the tank.
Suddenly that snakelike tube was jerked away from between the chunks of ore, and again the basket began a scraping advance.
Bormon's new lease on life brought its problems. What was about to happen? In a moment, now, Calbur would be ordered by the guard to dump his ore. They wouldn't have a chance, there on the catwalk. For Bormon's abrupt reappearance would bring swift extinction, probably to both.
The basket stopped. They had reached the ore-dump. Calbur's head and shoulders appeared. Behind the vision plate in his helmet there was a queer, set expression on his thin face. He thrust the ray-tube into Bormon's hands.
Bormon sprang erect, leaped from the basket. For a moment he stared around, locating the guard at the end of the catwalk. As yet the guard appeared not to have noticed anything unusual. But where was Calbur?
"Attention. One-six-nine. Dump your ore," ordered the guard, coldly, mechanically.
Something seemed to draw Bormon's eyes into focus on his own number stencil. One-six-nine, he read. Calbur's number! And then, suddenly, he realized the dreadful, admirable thing Keith Calbur had done....
For Calbur had leaped through the ore-chute, into the cyclotron's maelstromic heart! Despairing, he had chosen a way out. He had forfeited his life so that Bormon could take his place.