[Illustration: “My God ... watch out! It’s nitroglycerine!”] The Magnificent Possession By Isaac Asimov Walter Sills labored for years as an unknown laboratory worker--but at fifty he makes his great discovery! Fame, riches are to be his fate--until interference looms up in the form of a few unreliable characters--and Nature herself! Walter Sills reflected now, as he had reflected often before, that life was hard and joyless. He surveyed his dingy chemical laboratory and grinned cynically--working in a dirty hole of a place, living on occasional ore analyses that barely paid for absolutely indispensable equipment, while others, not half his worth perhaps, were working for big industrial concerns and taking life easy. He looked out the window at the Hudson River, ruddied in the flame of the dying sun, and wondered moodily whether these last experiments would finally bring him the fame and success he was after, or if they were merely some more false alarms. The unlocked door creaked open a crack and the cheerful face of Eugene Taylor burst into view. Sills waved and Taylor’s body followed his head and entered the laboratory. “Hello, old soak,” came the loud and carefree hail. “How go things?” Sills shook his head at the other’s exuberance. “I wish I had your foolish outlook on life, Gene. For your information, things are bad. I need money, and the more I need it, the less I have.” “Well, I haven’t any money either, have I?” demanded Taylor. “But why worry about it? You’re fifty, and worry hasn’t got you anything except a bald head. I’m thirty, and I want to keep my beautiful brown hair.” The chemist grinned. “I’ll get my money, yet, Gene. Just leave it to me.” “Your new ideas shaping out well?” “Are they? I haven’t told you much about it, have I? Well, come here and I’ll show you what progress I’ve made.” Taylor followed Sills to a small table, on which stood a rack of test-tubes, in one of which was about half an inch of a shiny metallic substance. “Sodium-mercury mixture, or sodium amalgam, as it is called,” explained Sills, pointing to it. He took a bottle labeled “Ammonium Chloride Sol.” from the shelf and poured a little into the tube. Immediately the sodium amalgam began changing into a loosely-packed, spongy substance. “That,” observed Sills, “is ammonium amalgam. The ammonium radical (NH₄) acts as a metal here and combines with mercury.” He waited for the action to go to completion and then poured off the supernatant liquid. “Ammonium amalgam isn’t very stable,” he informed Taylor, “so I’ll have to work fast.” He grasped a flask of straw-colored, pleasant-smelling liquid and filled the test-tube with it. Upon shaking, the loosely-packed ammonium amalgam vanished and in its stead a small drop of metallic liquid rolled about the bottom. Taylor gazed at the test-tube, open-mouthed. “What happened?”