He seemed to become aware for a moment as a last flicker of consciousness crossed his mind. He mouthed something unintelligible--a last, forgotten word. Anchored only by his grip on the control knobs, his weightless body floated aimlessly in the almost steaming cabin as the awful stillness re-echoed throughout the hollow vault of the ship. Down below, with ever-growing closeness, the Sun waited patiently, like a bright and hovering vulture. The MR4 swung and pivoted gently like a ship at sea straining at its anchor in the first, fresh breezes of a gathering storm. For a moment it seemed to hesitate like a coy maiden on the verge of some unknown threshold. Then, abruptly, she climaxed her voyage and plunged directly toward the waiting Sun some twenty million miles below, carrying with her only her dead cargo; her pilot-- * * * * * The radio crackled noisily after Hal Burnett's last incoherent transmission. It crackled aimlessly for a few moments--and then was still. "Something's wrong," said Williams, a thin thread of moisture shining down his face. "Something's gone wrong up there!" "It sure has," said Donnelly, quietly. "And I know who I'm going to ask about it." The little doctor said nothing. His face was an embittered parchment mask. "It's happened. God help me. It's happened. He's gone," he muttered, almost inaudibly. Donnelly sighed heavily, a look almost of defeat sweeping momentarily across his features. "See here, Doc," he said exhaustedly. "Don't be so heartless about people. You've got a son of your own in space, so you ought to understand how other people feel. What kind of a father would do a thing like this to another man's son anyway?" "Look, Donnelly," said the little man with bitter weariness. "Do me a favor will you? You fill out the reports tonight. Somehow or other I just don't feel up to it." "Maybe it's your conscience," said Donnelly, sarcastically. "But I'll be damned if I'll do it for you. You don't like to do your own dirty work, do you, Doc? I thought you just loved to fill out Government reports." "Donnelly, Donnelly," cried the doctor in sudden anguish. "Can't you understand yet. Even an undertaker's job is unpleasant but somebody's got to do it. Don't you see yet? _It has to be done!_" With a muffled groan of disgust, Donnelly sprang to the radio once again, pushing Williams roughly aside. Futilely, and in desperation he strained at the controls for a moment and then, with a roar of fury, he turned back to the doctor. "Now see here, Doc--" he thundered, and then stopped in amazement. The door to the dim and ill-lighted outer hallway of the lab was standing open. And at the far end, the outer door was quietly closing behind the disappearing figure of the bent-shouldered little man. Donnelly started to spring after him, and then abruptly stopped. His huge figure slumped in sudden despairing futility as he recognized the tragic hopelessness of the situation.