“There are many other processes—_some_ day you will understand them all. But for now—let me show you the result. “The pure earthlight passes last of all into my projector. See it here?” He laid his hand on what looked to Tubby something like a magic lantern. “My operating power is electricity.” He turned a switch. Tubby first heard a low hum and then a whirring, clicking sound. “This projector magnifies the image—throws it up on a screen.” He pointed to the wall; Tubby saw a small square of canvas hung on the wall. “Now then,” the professor continued, his voice trembling with emotion, “that star my telescope is pointing at is now exactly nine hundred and twenty-seven and one half Light-years away. That means that eighteen hundred and fifty-five years ago to-night the light we are getting back now from that star left the earth. Do you know what was happening eighteen hundred and fifty-five years ago to-night?” “No,” said Tubby. “Yes. Lots of things.” “I can pick anything I want from the light,” the professor answered. “I merely tune my instruments differently. Like wireless, you know—it’s all a matter of vibration. I have picked the most important thing that was happening—the ‘Burning of Rome’!” He turned another switch; the clicking sound grew louder. On the sheet, Tubby saw a great city in flames. He seemed to be standing on a hill, looking down at it. In the foreground he saw the young Roman Emperor, with his mistress, his friends and his music, as they reclined at ease, watching the destruction. Tubby stared for a long time, fascinated. “You are looking into the past,” he heard the professor’s droning voice saying. “All that has been stored up in the light all these years. It is light itself—the work of God, not of man. “That is Nero sitting there. No one living to-day on this earth has ever seen him before. But there he is—Nero the Cruel, Emperor of Rome. _We_ see him, you and I, for we are looking into the past—looking into the past.” The professor’s voice trailed off into silence. Tubby stared breathlessly. His heart was beating fast; he was trembling all over. He felt suddenly a little faint. He was in a cold sweat, and he sat down abruptly in a little wooden chair beside the Light Machine. The scene before him was very vivid; he could almost hear the Emperor’s music. Why, he _did_ hear music! Funny! The professor had not mentioned that. The clicking noise grew louder; the scene before him was so bright he could see nothing else around. It was very dark, and very close and stuffy. Where was the professor? Why didn’t he say something about the music? Tubby grew a little frightened. He shifted his feet uneasily. The little chair in which he was sitting was very uncomfortable. It cramped him; his back hurt. After a little while the scene before him slowly faded. The lights in the room flashed on; a rustling, and a shuffling of many feet sounded in his ears. Tubby sat up abruptly, blinking in the sudden light.