After a while, he stopped struggling. * * * * * The first sound he heard was not a sound at all, but a vibration, low, deep seated, swallowing his whole body as he lay there. He tried to sit up, and felt the leather bands catch his arms and legs and chest. He let out a little cry, and fumbled to unbuckle them, and then he rolled and spun crazily through the air until his boots struck metal, and caught him tight to the floor. A pang of nausea shot through him; he stared wide-eyed at the empty cabin, the dozen slanted acceleration cots, all empty. He struggled to the closed hatchway in front, and fought it open, his mind screaming. And then he was in the control room, staring at the empty seats in front of the panel, and above the rows of glittering keys, the curved plexiglass giving out to the black expanse of space with its millions of bright pinpoints. He gave a strangled cry, and pushed up against the glass, staring down at the still-dwindling discs below him, one pale greenish-blue, the other, much smaller, dead white against the blackness. And then he was clawing the glass, screaming and sobbing and cursing like a madman. He stared out the glass, and down at the panel, and slowly, like a malignant poison seeping into his mind, he began to realize what it meant. He knew now where he was going. He knew now the price-tag. Not to Venus, not to Mars--it would be too easy to return from there, it would be idiotic to shanghai a person aboard a ship to take him to Mars or Venus--he could simply turn around and come back home. Not to Venus, not to Mars. Not anywhere in the Solar System-- He saw it clearly, as bits of evidence fell into place. Man had been aiming at the stars for centuries. It was sure to come; the frontier had expanded year by year--across Africa, across Asia, across Antarctica--to the moon, to the planets. Always the expanding frontier, until now, when it had expanded beyond man's reach. For man could not go to the stars. There was no light-speed drive to carry him there, the journey would take too long. Once a man had grown to maturity, and been educated, and reached an age where he could move out on the long journey, he would be too old. The journey could never take less than twenty-five or thirty years, with the rocket drive man had, and man would be too old to be useful when he arrived at his destination. A man aged 25 at the start of the journey would spend his prime years in transit; he would be fifty, or sixty, or seventy or more before he arrived. There could be no round trips, there could be no exploration, or colonization, or anything else. Man would be too old-- _Unless he be born again_--