Authors: Arthur C Clarke
'Still, all this is guesswork. Now I'm going to show you something which I think is just as exciting.'
He led us into a room with walls consisting almost entirely of glass cages, full of creatures which at first sight I could not identify. Then I gave a gasp of astonishment.
'They're flies! But—where did they come from?'
They were flies, all right. Only one thing was wrong—these flies were a foot or more in wing-span.
Dr Hawkins chuckled.
'Lack of gravity, again, plus a few special hormones. Down on Earth, you know, an animal's weight has a major effect on controlling its size. A fly this size couldn't possibly lift itself into the air. It's odd to watch these flying—you can see the wing-beats quite easily.'
'What kind of flies are they?' asked Tim.
'
Drosophila
—fruit flies. They breed rapidly, and have been studied on Earth for about a century and a half. I can trace this fellow's family tree back to around 1920!'
Personally, I could think of much more exciting occupations, but presumably the biologists knew what they were doing. Certainly the final result was highly impressive—and unpleasant. Flies aren't pretty creatures, even when normal size…
'Now there's a bit of a contrast,' said Dr Hawkins, making some adjustments to a large projection microscope. 'You can just about see this chap with the naked eye—in the ordinary way, that is.'
He flicked a switch, and a circle of light flashed on the screen. We were looking into a tiny drop of water, with strange blobs of jelly and minute living creatures drifting through the field of vision. And there in the centre of the picture, waving its tentacles lazily, was—
'Why,' exclaimed Ron, 'that's the creature that caught us!'
'You're quite right,' replied Dr Hawkins. 'It's called a hydra, and a big one is only about a tenth of an inch long. So you see Cuthbert didn't come from Mars or Venus—but from Earth. He's our most ambitious experiment yet.'
'But what's the idea?' asked Tim.
'Well, you can study these creatures much more easily when they're this size. Our knowledge of living matter has increased enormously since we've been able to do this sort of thing. I must admit, though, that we rather overdid it with Cuthbert. It takes a lot of effort to keep him alive, and we're not likely to try and beat this record.'
After that, we were taken to see Cuthbert again. The lights were switched on this time—it seemed that we'd stumbled into the lab. during one of the short periods of artificial 'night'. Though we knew that the creature was safe, we wouldn't go very close. Tim Benton, however, was persuaded to offer a piece of raw meat, which was grabbed by a slim tentacle and tucked into the top of the long, slender 'trunk'.
'I should have explained,' said Dr Hawkins, 'that hydras normally paralyse their victims by stinging them. There are poison buds all along those tentacles—but we've been able to neutralize them. Otherwise Cuthbert would be as dangerous as a cageful of cobras.'
I felt like saying I didn't really think much of their taste in pets—but I remembered in time that we were, after all, guests here…
Another highlight of our stay at the Hospital was the visit to the Gravity Section. I've already mentioned that some of the space-stations produce a kind of artificial gravity by spinning slowly on their axes. Inside the Hospital they had a huge drum—a centrifuge—that did the same thing. We were given a ride in it, partly for fun and partly as a serious test of our reactions to having weight again.
The gravity chamber was a cylinder about fifty feet in diameter, supported on pivots at either end and driven by electric motors. We entered through a hatch in the side, and found ourselves in a small room that would have seemed perfectly normal down on Earth. There were pictures hanging from the walls, and even an electric light fitting suspended from the 'ceiling'. Everything had been done to create an impression, as far as the eye was concerned, that 'up' and 'down' existed again.
We sat in comfortable chairs and waited. Presently there was a gentle vibration and a sense of movement: the chamber was beginning to turn. Very slowly, a feeling of heaviness began to steal over me. My legs and arms required an effort to move them: I was a slave of gravity again, no longer able to glide through the air as freely as a bird…
A concealed loudspeaker gave us our instructions.
'We'll hold the speed constant now. Get up and walk around—but be careful.'
I rose from my seat—and almost fell back again with the effort.
'Gosh!' I exclaimed. 'How much weight have they given us? I feel as if I'm on Jupiter!'
My words must have been picked up by the operator, because the loudspeaker gave a chuckle.
'You're just half the weight you were back on Earth. But it seems a lot, doesn't it, after you've had none at all for a couple of weeks!'
It was a thought that made me feel rather unhappy. When I got down to Earth again, I'd weigh twice as much as this! Our instructor must have guessed my thoughts.
'No need to worry—you got used to it quickly enough on the way out, and it will be the same on the way back. You'll just have to take things easily for a few days when you get down to Earth, and try and remember that you can't jump out of top floor windows and float gently to the ground.'
Put that way, it sounded silly—but this was just the sort of thing I'd grown accustomed to doing here. I wondered how many spacemen had broken their necks when they got back to Earth…
In the centrifuge, we tried out all the tricks that were impossible under zero gravity. It was funny to watch Liquids pour in a thin stream, and remain quietly at the bottom of a glass. I kept on making little jumps, just for the novel experience of coming down quickly again in the same place.
Finally we were ordered back to our seats, the brakes put on, and the spin of the chamber was stopped. We were weightless again—back to normal!
I wish we could have stayed in the Hospital Station for a week or so, in order to explore the place thoroughly. It had everything that the Inner Station lacked and my companions, who hadn't been to Earth for months, appreciated the luxury even more than I did. It was strange seeing shops and gardens—and even going to the theatre.
That
was quite an unforgettable experience. Thanks to the absence of gravity, one could pack a large audience into a small space and everyone could get a good view. But it created a very difficult problem for the producer, as he had to give an illusion of gravity somehow. It wouldn't do, in a Shakespeare play, for all the characters to be floating around in mid-air. So the actors had to use magnetic shoes—a favourite dodge of the old science-fiction writers, though this was the only time I ever found them used in reality.
The play we saw was
Macbeth
. Personally, I don't care for Shakespeare and I only went along because we'd been invited and it would have been rude to stay away. But I was glad I went, if only because it was quite a tonic to see how the patients were enjoying themselves. And not many people can claim that they've seen Lady Macbeth, in the sleep-walking scene, coming down the stairs with magnetic shoes…
Another reason why I was in no great hurry to return to the Inner Station was simply this—in three days' time I'd have to go aboard the freighter scheduled to take me home. Although I'd been mighty lucky to get out here to the Space Hospital, there were still a lot of things I hadn't seen. There were the Met. Stations—the great observatories with their huge, floating telescopes—and the Relay Stations, another seven thousand miles farther out into space. Well, they would simply have to wait for another time.
Before the ferry rocket arrived to take us home, we had the satisfaction of knowing that our mission had been successful. The patient was off the danger list, and had a good chance of making a complete recovery. But—and this certainly gave the whole thing an ironic twist—it wouldn't be safe for him to go down to Earth. He'd come all those scores of millions of miles for nothing. The best he could do would be to look down on Earth through observation telescopes, watching the green fields on which he could never walk again. When his convalescence was over, he'd have to go back to Mars and its lower gravity.
The ferry rocket that came up to fetch us home had been diverted from its normal run between the Observatory Stations. When we were aboard, Tim Benton was still arguing with the Commander. No—arguing wasn't the right word: no one did
that
with Commander Doyle. But he was saying very wistfully, that it really was a great pity that we couldn't go back in the
Morning Star
. The Commander only grinned and said: 'Wait until you see the report of her overhaul—then you may change your mind. I bet she needs new tube-linings, at the very least. I'll feel a bit happier in a ship that's a hundred years younger!'
Still, as things turned out, I'm pretty sure the Commander wished he'd listened to us…
It was the first time I'd been aboard one of the low-powered inter-orbit ferries—unless one includes our home-built
Skylark of Space
in this category. The control cabin was much like that of any other spaceship, but from the outside the vessel looked very peculiar indeed. It had been built here in space and, of course, had no streamlining or fins. The cabin was roughly egg-shaped, and connected by three open girders to the fuel tanks and rocket motors. Most of the freight was not taken inside the ship but was simply lashed to what were rather appropriately called the luggage racks'—a series of wire-mesh nets supported on struts. For stores that had to be kept under normal pressure, there was a small hold with a second air-lock just behind the control cabin. The whole ship had certainly been built for efficiency rather than beauty.
The pilot was waiting for us when we went aboard, and Commander Doyle spent some time discussing our course with him.
That's not his job,' Norman whispered in my ear, 'but the old boy's so glad to be out in space again that he can't help it.' I was going to say that I thought the Commander spent
all
his time in space: then I realized that, from some points of view, his office aboard the Inner Station wasn't so very different from an office down on Earth…
We had nearly an hour before take-off—ample time for all checks and last-minute adjustments that would be needed. I got into the nearest bunk to the observation port, so that I could look back at the Hospital as we dropped away from its orbit and fell down towards Earth. It was hard to believe that this great blossom of glass and plastic, floating here in space with the sun pouring into its wards, laboratories and observation decks, was really spinning round the world at eight thousand miles an hour. As I waited for the voyage to begin, I remembered the attempts I'd made to explain the space-stations to Mom. Like a lot of people, she could never really understand why they 'didn't fall down'.
'Look, Mom,' I'd said, 'they're moving mighty fast, going around the Earth in a big circle. And when anything moves like this, you get centrifugal force. It's just the same when you whirl a stone at the end of a string.'
'I don't whirl stones on the end of strings,' said Mom, 'and I hope you won't either—at least not indoors.'
'I was only giving an example,' I said impatiently. 'It's the one they always use at school. Just as the stone can't fly away because of the pull of the string, so a space-station has to stay there because of the pull of gravity. Once it's given the right speed, it'll stay there for ever without using any power. It can't
lose
speed, because there's no air-resistance. Of course, the speed's got to be calculated carefully. Near the Earth, where gravity's mighty powerful, a station has to move fast to stay up. It's like tying your stone on to a short piece of string—you have to whirl it quickly. But a long way out, where gravity's weaker, the stations can move slowly.'
'Yes,' said Mom. 'I knew it was something like that. But what worries me is this—suppose one of the stations
did
lose a bit of speed. Wouldn't it come falling down? The whole thing looks dangerous to me. It seems a sort of balancing act. If anything goes wrong—'
I hadn't known the answer then, so I'd only been able to say: 'Well, the
Moon
doesn't fall down, and it stays up just the same way.' It wasn't until I got to the Inner Station that I learned the answer, though I should have been able to work it out for myself. If the velocity of a space-station
did
drop a bit, it would simply move into a closer orbit. You'd have to carve off quite a lot of its speed before it came dangerously close to Earth—and it would take a vast amount of rocket braking to do this. It couldn't possibly happen by accident.
I looked at the clock. Another thirty minutes to go. Funny—why do I feel so sleepy now?—I had a good rest last night. Perhaps the excitement's been a bit too much. Well, let's just relax and take things easy—there's nothing to do until we reach the Inner Station in four hours' time. Or is it four days'? I really can't remember, but anyway it isn't important. Nothing is important any more—not even the fact that everything around me is half-hidden in a pink mist—
And then I heard Commander Doyle shouting. He sounded miles away, and though I had an idea that the words he was calling should mean something, I didn't know what it was. They were still ringing vainly in my ears when I blacked out completely: 'Emergency Oxygen!'