Outward. Tiny Pluto was too far off to be seen, but its orbit was passed. For a hundred years, the outpost of the solar system. Now dethroned by the enormous newcomer, its passing was still a solemn moment. Then, one day Barth observed a tiny light where no light should be. Celebration again rang through the vessel: Planet P was sighted! Days of deceleration followed. The rockets flamed, but no longer from the stern of the vessel. Days of a continual blasting from the vessel's prow until at last the unbelievable acceleration was neutralized. Now the planet had grown, until, even with their greatly decreased speed, it filled the view. Still more blasting until the ship was virtually drifting along, caught only by the gravity of the monstrous new world. A great disk glowing dimly in the light of the stars, especially in the light of one particularly brilliant star that was the Earthmen's sun. The vaguest hints of geological features could be seen. Planet P. The rockets flared again in an intricate pattern. Balanced on the pattern, the ship was lowered, slowly, into the atmosphere of the strange world. About it flamed a red glow as proof of atmosphere. An atmosphere, doubtless, of some unknown gases that would not congeal in the awful cold. And, finally, a shrill whistling penetrating the triple-thick walls, a dull thud, and a silence as she came to rest. The voyage was over. Man had reached the outermost limits of the solar system, had arrived safely at the mysterious outer world, Planet P. * * * * * The men gathered in space suits. "Each man will take searchlights and emergency rations. You will obey Lieutenant Rokesmith and myself implicitly; only on pledges of such obedience from all of you can I permit a planet-party to land." Each member of the crew spoke his agreement. "Mullins, take a coil of rope; Weber, the barometer and compass; Barth, the camera and flash. Are you sure your gravity controls are adjusted to decrease your weight to Earth normal? Make sure, everyone--that goes for me, too." "Check!" Rokesmith turned the lever and swung the thick outer port open. Wanderman stepped out onto the ground; the others followed. Above them was a deep blue sky strewn with stars, though lacking in the abundant distribution of the outer void. Beneath their feet lay a clay-like expanse. They looked about them. There was something dark looming up in the starlight a distance away. The captain started off in that direction, beckoned the others to follow. All felt that strange sensation that comes for everyone when he stands on the terrain of an alien planet. It makes no difference how often this experience has been undergone previously; the sensation cannot be shaken off. "It looks like a wall," sang out Opp as they reached the looming thing. Rokesmith turned the beam of his flashlight on it. "It is a wall!" * * * * *