The deck was deserted, lit only by three dim blue globes, hanging from the curved roof. All seemed in order--the fire-fighting equipment hanging on the walls, and the huge metal patches and welding equipment for repairing breaks in the hull. Everything was clean, bright with polish or new paint. And all was very still. The silence held a vague, brooding threat that frightened Thad, made him wish for a moment that he was back upon his rugged ball of metal. But he banished his fear, and strode down the deck. Midway of it he found a dark stain upon the clean metal. The black of long-dried blood. A few tattered scraps of cloth beside it. No more than bloody rags. And a heavy meat cleaver, half hidden beneath a bit of darkened fabric. Mute record of tragedy! Thad strove to read it. Had a man fought here and been killed? It must have been a struggle of peculiar violence, to judge by the dark spattered stains, and the indescribable condition of the remnants of clothing. But what had he fought? Another man, or some thing? And what had become of victor and vanquished? He walked on down the deck. The torturing silence was broken by the abrupt patter of quick little footsteps behind him. He turned quickly, nervously, with a hand going instinctively to his welding arc, which, he knew, would make a fairly effective weapon. * * * * * It was merely a dog. A little dog, yellow, nondescript, pathetically delighted. With a sharp, eager bark, it leaped up at Thad, pawing at his armor and licking it, standing on its hind legs and reaching toward the visor of his helmet. It was very thin, as if from long starvation. Both ears were ragged and bloody, and there was a long, unhealed scratch across the shoulder, somewhat inflamed, but not a serious wound. The bright, eager eyes were alight with joy. But Thad thought he saw fear in them. And even through the stiff fabric of the Osprey suit, he felt that the dog was trembling. Suddenly, with a low whine, it shrank close to his side. And another sound reached Thad's ears. A cry, weird and harrowing beyond telling. A scream so thin and so high that it roughened his skin, so keenly shrill that it tortured his nerves; a sound of that peculiar frequency that is more agonizing than any bodily pain. When silence came again, Thad was standing with his back against the wall, the welding arc in his hand. His face was cold with sweat, and a queer chill prickled up and down his spine. The yellow dog crouched whimpering against his legs. Ominous, threatening stillness filled the ship again, disturbed only by the whimpers and frightened growls of the dog. Trying to calm his overwrought nerves, Thad listened--strained his ears. He could hear nothing. And he had no idea from which direction the terrifying sound had come.