"It's not worrying me," I replied, watching him closely. "I have enjoyed a very remarkable, a very pleasant experience. If you should care to remain aboard the _Ertak_, I should like exceedingly to have you accompany us to our Base, where I could place you in touch with other laboratory men, with whom you would have much in common." Harbauer threw back his head and laughed--not pleasantly. "Thanks!" he said. "But I have no time for that. They could give me no knowledge that I need, now; you have told me and showed me enough. I understand how you have released atomic energy; it is a matter so simple that a child should have guessed it, and man has wondered about it for centuries, knowing that the power was there, but lacking a key to unfetter it. And now I have that key!" "True. But perhaps our scientists would like, in exchange, the secret of moving forward in time," I suggested, reasonably enough. "What do I care about them?" snapped Harbauer. He loosened the cord of the robe with a quick, impatient gesture, as though it confined him too tightly, and threw the garment from him. * * * * * Then, suddenly, he took a quick stride toward me, and thrust out his ugly head. "I know enough now to give me power over all my world," he cried. "Haven't you guessed the reason for my interest in your engines of destruction? I came down the centuries ahead of my generation so that I might come back with power in my hand; power to wipe out the fools who have made a mock of me. And I have that power--here!" He tapped his forehead dramatically with his left hand. "I will bring a new regime to my era!" he continued, fairly shouting now. "I will be what many men have tried to be, and what no man has ever been--master of the world! Absolute, unquestioned, supreme master!" He paused, his eyes glaring into mine--and I knew from the light that shone behind those long, narrow slits, that I was dealing with a madman. "True; you will," I said gently, moving carelessly toward the microphone. With that in my hand, a slight pressure on the General Attention signal, and I would have the whole crew of the _Ertak_ here in a moment. But I had explained the workings of the navigating room's equipment only too well. "Stop!" snarled Harbauer, and his right hand flashed up. "See this? Perhaps you don't know what it is; I'll tell you. It's an automatic pistol--not so efficient as your disintegrator-ray, but deadly enough. There is certain death for eight men in my hand. Understand?" "Perfectly." What an utter fool I had been! I was not armed, and I knew that Harbauer spoke the truth. I had often seen weapons similar to the one he held in the military museums. They are still there, if you are curious--rusty and broken, but not unlike our present atomic pistols in general appearance. They propelled the bullet by the explosion of a sort of powder; inefficient, of course, but, as he had said, deadly enough for the purpose.