2
The pressure of three gravities continued. Joe's chest muscles ached with the exertion of breathing over so long a period. Six gravities for fourteen seconds had been a ghastly ordeal. Three gravities for minutes built up to something nearly as bad. Joe's heart began to feel fatigue, and a man's heart normally simply doesn't ever feel tired. It became more and more difficult to see clearly.
But he had work to do. Important work. The take-off rockets were solid-fuel jobs, like those which launched the Platform. They were wire-wound steel tubes lined with a very special refractory, with unstable beryllium and fluorine compounds in them. The solid fuel burned at so many inches per second. The refractory crumbled away and was hurled astern at a corresponding rate—save for one small point. The refractory was not all exactly alike. Some parts of it crumbled away faster, leaving a pattern of baffles which acted like a maxim silencer on a rifle, or like an automobile muffler. The baffles set up eddies in the gas stream and produced exactly the effect of a rocket motor's throat. But the baffles themselves crumbled and were flung astern, so that the solid-fuel rockets had always the efficiency of gas-throated rocket motors; and yet every bit of refractory was reaction-mass to be hurled astern, and even the steel tubes melted and were hurled away with a gain in acceleration to the ship. Every fraction of every ounce of rocket mass was used for drive. No tanks or pumps or burners rode deadhead after they ceased to be useful.
But solid-fuel rockets simply can't be made to burn with absolute evenness as a team. Minute differences in burning-rates do tend to cancel out. But now and again they reinforce each other and if uncorrected will throw a ship off course. Gyros can't handle such effects. So Joe had to watch his instruments and listen to the tinny voice behind him and steer the ship against accidental wobblings as the Earth fell away behind him.
He battled against the fatigue of continuing to live, and struggled with gyros and steering jets to keep the ship on its hair-line course. He panted heavily. The beating of his heart became such a heavy pounding that it seemed that his whole body shook with it. He had to do infinitely fine precision steering with hands that weighed pounds and arms that weighed scores of pounds and a body that had an effective weight of almost a quarter of a ton.
And this went on and went on and on for what seemed several centuries.
Then the voice in the speaker said thickly: "Everything is in the clear. In ten seconds you can release your rockets. Shall I count?"
Joe panted, "Count!"
The mechanical voice said, "Seven ... six ... five ... four ... three ... two ... one ... cut!"