Ds afterward, there was silence. Then there came a soft rumble, as of water beginning to boil in some huge but distant samovar. It seemed to go on and on and on. And there was a bluish, fluctuating glow on the horizon. _Radioactivity?_ Wang wondered. Surely not an atomic-powered ship without safety cutoffs in this day and age. Still, there was always the possibility that the cutoffs had failed. He pulled out his radiophone and thumbed the call button again. This time there was no delay. "Yes?" "How are the radiation detectors behaving there, Grandfather?" "One moment. I shall see." There was a silence. Then: "No unusual activity, young Wang. Why?" Wang told him. Then he asked: "Did you get hold of the air transport authorities?" "Yes. They have no missing aircraft, but they're checking with the space fields. The way you describe it, the thing must be a spaceship of some kind." "I think so too. I wish I had a radiation detector here, though. I'd like to know whether that thing is hot or not. It's only a couple of miles away--maybe a little more--and if that blue glow is ionization caused by radiation, it's much too close for comfort." "I think any source that strong would register on our detectors here, young Wang," said the old man in his dry voice. "However, I agree that it might not be the pinnacle of wisdom to approach the source too closely." "Clear your mind of worry, Grandfather," Wang said. "I accept your words of wisdom and will go no nearer. Meanwhile, you had best put in a call to Central Headquarters Fire Control. There's going to be a blaze if I'm any judge unless they get here fast with plenty of fire equipment." "I'll see to it," said his grandfather, cutting off. The bluish glow in the sky had quite died away by now, and the distant rumbling was fading, too. And, oddly enough, there was not much smoke in the distance. There was a small cloud of gray vapor that rose, streamer-like, fr
