MacKinnon peered out of a forward port of the big transport helicopter with repressed excitement in his heart. There! That must be it-that black band in the distance. The helicopter drew closer, and he became certain that he was seeing the Barrier-the mysterious, impenetrable wall that divided the United States from the reservation known as Coventry. His guard looked up from the magazine he was reading and followed his gaze. 'Nearly there, I see,' he said pleasantly. 'Well, it won't be long now.' 'It can't be any too soon for me!' The guard looked at him quizzically, but with tolerance. 'Pretty anxious to get on with it, eh?' MacKinnon held his head high. 'You've never brought a man to the Gateway who was more anxious to pass through!' 'Mmm-maybe. They all say that, you know. Nobody goes through the Gate against his own will.' 'I mean it!' 'They all do. Some of them come back, just the same.' 'Say-maybe you can give me some dope as to conditions inside?' 'Sorry,' the guard said, shaking his head, 'but that is no concern of the United States, nor of any of its employees. You'll know soon enough.' MacKinnon frowned a little. 'It seems strange-I tried inquiring, but found no one who would admit that they had any notion about the inside. And yet you say that some come out. Surely some of them must talk...' 'That's simple,' smiled the guard, 'part of their reorientation is a subconscious compulsion not to discuss their experiences.' 'That's a pretty scabby trick. Why should the government deliberately conspire to prevent me, and the people like me, from knowing what we are going up against?' 'Listen, buddy,' the guard answered, with mild exasperation, 'you've told the rest of us to go to the devil. You've told us that you could get along without us. You are being given plenty of living room in some of the best land on this continent, and you are being allowed to take with you everything that you own, or your credit could buy. What the deuce else do you expect?' MacKinnon's face settled in obstinate lines. 'What assurance have I that there will be any land left for me?' 'That's your problem. The government sees to it that there is plenty of land for the population. The divvy-up is something you rugged individualists have to settle among yourselves. You've turned down our type of social co-operation; why should you expect the safeguards of our organization?' The guard turned back to his reading and ignored him. They landed on a small field which lay close under the blank black wall. No gate was apparent, but a guardhouse was located at the side of the field. MacKinnon was the only passenger. While his escort went over to the guardhouse, he descended from the passenger compartment and went around to the freight hold. Two members of the crew were letting down a ramp from the cargo port. When he appeared, one of them eyed him, and said, 'O.K., there's your stuff. Help yourself.' He sized up the job, and said, 'It's quite a lot, isn't it? I'll need some help. Will you give me a hand with it?' The crew member addressed paused to light a cigarette before replying, 'It's your stuff. If you want it, get it out. We take off in ten minutes.' The two walked around him and reentered the ship. 'Why, you-' MacKinnon shut up and kept the rest of his anger to himself. The surly louts! Gone was the faintest trace of regret at leaving civilization. He'd show them! He could get along without them. But it was twenty minutes and more before he stood beside his heaped up belongings and watched the ship rise. Fortunately the skipper had not been adamant about the time limit. He turned and commenced loading his steel tortoise. Under the romantic influence of the classic literature of a bygone day he had considered using a string of burros, but had been unable to find a zoo that would sell them to him. It was just as well-he was completely ignorant of the limits, foibles, habits, vices, illnesses, and care of those useful little beasts, and unaware of his own ignorance. Master and servant would have vied in making each other unhappy. The vehicle he had chosen was not an unreasonable substitute for burros. It was extremely rugged, easy to operate, and almost foolproof. It drew its power from six square yards of sunpower screens on its low curved roof. These drove a constant-load motor, or, when halted, replenished the storage battery against cloudy weather, or night travel. The bearings were 'everlasting', and every moving part, other than the caterpillar treads and the controls, were sealed up, secure from inexpert tinkering. It could maintain a steady six miles per hour on smooth, level pavement. When confronted by hills, or rough terrain, it did not stop, but simply slowed until the task demanded equaled its steady power output. The steel tortoise gave MacKinnon a feeling of Crusoe-like independence. It did not occur to him his chattel was the end product of the cumulative effort and intelligent co-operation of hundreds of thousands of men, living and dead. He had been used all his life to the unfailing service of much more intricate machinery, and honestly regarded the tortoise as a piece of equipment of the same primitive level as a wood-man's axe, or a hunting knife. His talents had been devoted in the past to literary criticism rather than engineering, but that did not prevent him from believing that his native intelligence and the aid of a few reference books would be all that he would really need to duplicate the tortoise, if necessary. Metal ores were necessary, he knew, but saw no obstacle in that, his knowledge of the difficulties of prospecting, mining, and metallurgy being as sketchy as his knowledge of burros. His goods filled every compartment of the compact little freighter. He checked the last item from his inventory and ran a satisfied eye down the list. Any explorer or adventurer of the past might well be pleased with such equipment, he thought. He could imagine showing Jack London his knockdown cabin. See, Jack, he would say, it's proof against any kind of weather-perfectly insulated walls and floor-and can't rust. It's so light that you can set it up in five minutes by yourself, yet it's so strong that you can sleep sound with the biggest grizzly in the world snuffling right outside your door. And London would scratch his head, and say, Dave, you're a wonder. If I'd had that in the Yukon, it would have been a cinch! He checked over the list again. Enough concentrated and desiccated food and vitamin concentrate to last six months. That would give him time enough to build hothouses for hydroponics, and get his seeds started. Medical supplies-he did not expect to need those, but foresight was always best. Reference books of all sorts. A light sporting rifle-vintage: last century. His face clouded a little at this. The War Department had positively refused to sell him a portable blaster. When he had claimed the right of common social heritage, they had grudgingly provided him with the plans and specifications, and told him to build his own. Well, he would, the first spare time he got. Everything else was in order. MacKinnon climbed into the cockpit, grasped the two hand controls, and swung the nose of the tortoise toward the guardhouse. He had been ignored since the ship had landed; he wanted to have the gate opened and to leave. Several soldiers were gathered around the guardhouse. He picked out a legate by the silver stripe down the side of his kilt and spoke to him. 'I'm ready to leave. Will you kindly open the Gate?' 'O.K.,' the officer answered him, and turned to a soldier who wore the plain gray kilt of a private's field uniform. 'Jenkins, tell the power house to dilate-about a number three opening, tell them,' he added, sizing up the dimensions of the tortoise. He turned to MacKinnon. 'It is my duty to tell you that you may return to civilization, even now, by agreeing to be hospitalized for your neurosis.' 'I have no neurosis!' 'Very well. If you change your mind at any future time, return to the place where you entered. There is an alarm there with which you may signal to the guard that you wish the gate opened.' 'I can't imagine needing to know that.' The legate shrugged. 'Perhaps not-but we send refugees to quarantine all the time. If I were making the rules, it might be harder to get out again.' He was cut off by the ringing of an alarm. The soldiers near them moved smartly away, drawing their blasters from their belts as they ran. The ugly snout of a fixed blaster poked out over the top of the guardhouse and pointed toward the Barrier. The legate answered the question on MacKinnon's face. 'The power house is ready to open up.' He waved smartly toward that building, then turned back. 'Drive straight through the center of the opening. It takes a lot of power to suspend the stasis; if you touch the edge, we'll have to pick up the pieces.' A tiny, bright dot appeared in the foot of the barrier opposite where they waited. It spread into a half circle across the lampblack nothingness. Now it was large enough for MacKinnon to see the countryside beyond through the arch it had formed. He peered eagerly. The opening grew until it was twenty feet wide, then stopped. It framed a scene of rugged, barren hills. He took this in, and turned angrily on the legate. 'I've been tricked!' he exclaimed. 'That's not fit land to support a man.' 'Don't be hasty,' he told MacKinnon. 'There's good land beyond. Besides-you don't have to enter. But if you are going, go!' MacKinnon flushed, and pulled back on both hand controls. The treads bit in and the tortoise lumbered away, straight for the Gateway to Coventry. When he was several yards beyond the Gate, he glanced back. The Barrier loomed behind him, with nothing to show where the opening had been. There was a little sheet metal shed adjacent to the point where he had passed through. He supposed that it contained the alarm the legate had mentioned, but he was not interested and turned his eyes back to his driving. Stretching before him, twisting between rocky hills, was a road of sorts. It was not paved and the surface had not been repaired recently, but the grade averaged downhill and the tortoise was able to maintain a respectable speed. He continued down it, n