The first tests confirmed what Craig had already presumed; that the explosion had been absolutely clean. What radiation existed had originated from molecules in the rock itself or in the vaporized snow.
There was no way of guessing at the type of blast; he only knew that mass had been transformed virtually one hundred per cent into energy in a very short period of time. No process Craig knew even approached it.
He stared again at the tunnel mouths. He was sure now that something had come out of them, risen about seven hundred feet above the plateau and released the blast. He trembled with eagerness to get inside, danger or no.
He had turned impatiently to Brulieres, when somewhere deep in the tunnels, shouting broke out. Two pistol shots echoed hollowly. There was a clatter of running footsteps. Craig found his right hand fumbling at his hip, and felt foolish. He hadn't carried a sidearm since Korea.
Lieutenant Rabar burst through the tunnel, stumbling in the sunlight, his face contorted. He ran straight across the plateau and threw himself over the edge. Dientes, who had jumped to his feet, was only a step behind him. Craig, eyes fastened on the tunnel, realized vaguely that the two must have landed in deep snow, since there was no sound of their falling.
A glow appeared in the tunnel. Craig fought the panic that seized him; stood his ground and was aware of Brulieres beside him. The glow brightened.
Its source came into sight—a ball of dazzling brilliance, oval and about the size of a man's torso. It emerged into sunlight and Craig saw that it was solid. It looked like incandescent metal, but he somehow felt that it wasn't hot. It seemed to move at will and to hover without support.
It acted alive.
It moved a little way toward Craig and Brulieres, then stopped. A tentative rumble came from it, like the beginning of thunder. Something like a tentacle lifted, clutching an object that resembled a flashlight. A blinding lance of heat shot from the object and struck the rock a few yards in front of the two men. A sound came from the rock like ice pressed upon a hot stove. Smoke puffed upward. The beam lasted only an instant, but it left a long curved scar in the rock.