It was not an experiment made at random, nor was the world to which it reached an unknown one to Tommy or to Denham. Months before, Denham had built an instrument which would bend a ray of light into the Fifth Dimension and had found that he could fix a telescope to the device and look into a new and wholly strange cosmos.* * “The Fifth-Dimension Catapult”—see the [January, 1931, issue of Astounding Stories]. He had seen tree-fern jungles and a monstrous red sun, and all the flora and fauna of a planet in the carboniferous period of development. More, by the accident of its placing he had seen the towers and the pinnacles of a city whose walls and towers seemed plated with gold.
Having gone so far, he had devised a catapult which literally flung objects to the surface of that incredible world. Insects, birds, and at last a cat had made the journey unharmed, and he had built a steel globe in which to attempt the journey in person. His daughter Evelyn had demanded to accompany him, and he believed it safe. The trip had been made in security, but return was another matter. A laboratory assistant, Von Holtz, had sent them into the Fifth Dimension, only to betray them. One King Jacaro, lord of Chicago racketeers, was convinced by him of the existence of the golden city of that other world, and that it was full of delectable loot. He offered a bribe past envy for the secret of Denham’s apparatus. And Von Holtz had removed the apparatus for Denham’s return before working the catapult to send him on his strange journey. He wanted to be free to sell full privileges of rapine and murder to Jacaro.
The result was unexpected. Von Holtz could not unravel the secret of the catapult he himself had operated. He could not sell the secret for which he had committed a crime. In desperation he called in Tommy Reames—rather more than an amateur in mathematical physics—showed him Evelyn and her father marooned in a tree-fern jungle, and hypocritically asked for aid.
Tommy’s enthusiastic efforts soon became more than merely enthusiastic. The men of the Golden City remained invisible, but there were strange, half-mad outlaws of the jungles who hated the city. Tommy Reames had watched helplessly as they hunted for the occupants of the steel globe. He had worked frenziedly to achieve a rescue. In the course of his labor he discovered the treachery of Von Holtz as well as the secret of the catapult, and with the aid of Smithers—who had helped to build the original catapult—he made a new small device to achieve the original end.
The whole affair came to an end on one mad afternoon when the Ragged Men captured first an inhabitant of the Golden City, and then Denham and Evelyn in a forlorn attempt at rescue. Tommy Reames went mad. He used a tiny sub-machine gun upon the Ragged Men through the model magnetic catapult he had made, and contrived communication with Denham afterward. Instructed by Denham, he brought about the return of father and daughter to Earth just before Ragged Men and Earthling alike would have perished in a vengeful gas cloud from the Golden City. Even then, though, his triumph was incomplete because Von Holtz had gotten word to Jacaro, and nattily-dressed gunmen raided the laboratory and made off with the model catapult, leaving three bullets in Tommy and one in Smithers as souvenirs.
Now, using the principle developed in the catapult, Tommy and Denham had built a large Tube, and as Tommy climbed along its corrugated interior he knew a good part of what he should expect at the other end. A steady current of air blew past him. It was laden with a myriad unfamiliar scents. The Tube was a tunnel from one set of dimensions to another, a permanent way from Earth to a strange, carboniferous-period planet on which a monstrous dull-red sun shone hotly. Tommy should come out into a tree-fern forest whose lush vegetation would hide the sky, and which furnished a lurking place not only for strange reptilian monsters akin to those of the long-dead past of Earth, but for the bands of ragged, half-mad human beings who were outlaws from the civilization of which Denham and Evelyn had seen proofs.
Tommy reached the third bend in the Tube. By now he had lost all sense of orientation. An object may be bent through one right angle only in two dimensions, and a second perfect right angle—at ninety degrees to all former paths—only in three dimensions. It follows that a third perfect right angle requires four dimensions for existence, and four perfect right angles five. The Tube bent itself through four perfect right angles, and since no human-being can ever have experience of more than three dimensions, plus time, it followed that Tommy was experiencing other dimensions than those of Earth as soon as he passed the third bend. In short, he was in another cosmos.
There was a moment of awful sickness as he passed the third bend. He was hideously dizzy when he passed the fourth. For a time he felt as if he had no weight at all. But then, quite abruptly, he was climbing vertically upward and the soughing of tree-fern fronds was loud in his ears, and suddenly the end of the Tube was under his fingers and he stared out into the world of the Fifth Dimension.