Tommy looked at that third mirror, and instantly his eyes ached. He closed them and opened them again. Again they stung horribly. It was exactly the sort of eye-strain which comes of looking through a lens which does not focus exactly, or through a strange pair of eyeglasses. He could see the third mirror, but his eyes hurt the instant they looked upon it, as if that third mirror were distorted in an impossible fashion. He was forced to draw them away. He could see, though, that somehow that third mirror would reflect his imaginary beam of light into a fourth mirror of which he could see only the edge. He moved his head—and still saw only the edge of a mirror. He was sure of what he saw, because he could look into the wavy, bluish translucency all glass shows upon its edge. He could even see the thin layer of silver backing. But he could not put himself into a position in which more than the edge of that mirror was visible.
“Good Lord!” said Tommy Reames feverishly. “That mirror—”
“A mirror at forty-five degrees,” said Von Holtz precisely, “reflects light at a right angle. There are four mirrors, and each bends a ray of light through a right angle which is also a right angle to all the others. The result is that the dimensoscope looks into what is a fifth dimension, into which no man ever looked before. But I cannot move other mirrors into the positions they have in this instrument. I do not know how.”
Tommy shook his head impatiently, staring at the so-simple, yet incredible device whose theory had been mathematically proven numberless times, but never put into practice before.
“Having made this device,” said Von Holtz, “the Herr Professor constructed what he termed a catapult. It was a coil of wire, like the large machine there. It jerked a steel ball first vertically, then horizontally, then laterally, then in a fourth-dimensional direction, and finally projected it violently off in a fifth-dimensional path. He made small hollow steel balls and sent a butterfly, a small sparrow, and finally a cat into that other world. The steel balls opened of themselves and freed those creatures. They seemed to suffer no distress. Therefore he concluded that it would be safe for him to go, himself. His daughter refused to permit him to go alone, and he was so sure of his safety that he allowed her to enter the globe with him. She did. I worked the catapult which flung the globe in the fifth dimension, and his device for returning failed to operate. Hence he is marooned.”
“But the big catapult—”
“Can you not see that the big catapult is broken?” demanded Von Holtz bitterly. “A special metal is required for the missing parts. That, I know how to make. Yes. I can supply that. But I cannot shape it! I cannot design the gears which will move it as it should be moved! I cannot make another dimensoscope. I cannot, Herr Reames, calculate any method of causing four right angles to be all at right angles to each other. It is my impossibility! It is for that that I have appealed to you. You see it has been done. I see that it is done. I can make the metal which alone can be moved in the necessary direction. But I cannot calculate any method of moving it in that direction! If you can do so, Herr Reames, we can perhaps save the Herr Professor Denham. If you cannot—Gott! The death he will die is horrible to think of!”
“And his daughter,” said Tommy grimly. “His daughter, also.”