Collected Stories Of Arthur C. Clarke (33 page)

It was warmer now, as if the ghosts of lost summers had returned to haunt the land. For whole days the temperature rose above freezing, while in many places flowers were breaking through the snow. Whatever was approaching from the north was nearer, and several times a day that enigmatic roar would go thundering over the city, sending the snow sliding upon a thousand roofs. There were strange, grinding undertones that Professor Millward found baffling and even ominous. At times it was almost as if he were listening to the clash of mighty armies, and sometimes a mad but dreadful thought came into his mind and would not be dismissed. Often he would wake in the night and imagine he heard the sound of mountains moving to the sea.

So the summer wore away, and as the sound of that distant battle drew steadily nearer Professor Millward was the prey of ever more violently alternating hopes and fears. Although he saw no more wolves or bears – they seemed to have fled southward – he did not risk leaving the safety of his fortress. Every morning he would climb to the highest window of the tower and search the northern horizon with field-glasses. But all he ever saw was the stubborn retreat of the snows above Hampstead, as they fought their bitter rearguard action against the sun.

His vigil ended with the last days of the brief summer. The grinding thunder in the night had been nearer than ever before, but there was still nothing to hint at its real distance from the city. Professor Millward felt no premonition as he climbed to the narrow window and raised his binoculars to the northern sky.

As a watcher from the walls of some threatened fortress might have seen the first sunlight glinting on the spears of an advancing army, so in that moment Professor Millward knew the truth. The air was crystal-clear, and the hills were sharp and brilliant against the cold blue of the sky. They had lost almost all their snow. Once he would have rejoiced at that, but it meant nothing now.

Overnight, the enemy he had forgotten had conquered the last defences and was preparing for the final onslaught. As he saw that deadly glitter along the crest of the doomed hills, Professor Millward understood at last the sound he had heard advancing for so many months. It was little wonder he had dreamed of mountains on the march.

Out of the North, their ancient home, returning in triumph to the lands they had once possessed, the glaciers had come again.

Hide-and-Seek

First published in
Astounding Science-Fiction
, September 1949

Collected in
Expedition to Earth

We were walking back through the woods when Kingman saw the grey squirrel. Our bag was a small but varied one – three grouse, four rabbits (one, I am sorry to say, an infant in arms) and a couple of pigeons. And contrary to certain dark forecasts, both the dogs were still alive.

The squirrel saw us at the same moment. It knew that it was marked for immediate execution as a result of the damage it had done to the trees on the estate, and perhaps it had lost close relatives to Kingman’s gun. In three leaps it had reached the base of the nearest tree, and vanished behind it in a flicker of grey. We saw its face once more, appearing for a moment round the edge of its shield a dozen feet from the ground: but though we waited, with guns levelled hopefully at various branches, we never saw it again.

Kingman was very thoughtful as we walked back across the lawn to the magnificent old house. He said nothing as we handed our victims to the cook – who received them without much enthusiasm – and only emerged from his reverie when we were sitting in the smoking-room and he remembered his duties as a host.

‘That tree-rat,’ he said suddenly – he always called them ‘tree-rats’, on the grounds that people were too sentimental to shoot the dear little squirrels – ‘it reminded me of a very peculiar experience that happened shortly before I retired. Very shortly indeed, in fact.’

‘I thought it would,’ said Carson dryly. I gave him a glare: he’d been in the Navy and had heard Kingman’s stories before but they were still new to me.

‘Of course,’ Kingman remarked, slightly nettled, ‘if you’d rather I didn’t—’

‘Do go on,’ I said hastily. ‘You’ve made me curious. What connection there can possibly be between a grey squirrel and the Second Jovian War I can’t imagine.’

Kingman seemed mollified.

‘I think I’d better change some names,’ he said thoughtfully, ‘but I won’t alter the places. The story begins about a million kilometres sunwards of Mars—’

*

K.15 was a military intelligence operative. It gave him considerable pain when unimaginative people called him a spy but at the moment he had much more substantial grounds for complaint. For some days now a fast cruiser had been coming up astern, and though it was flattering to have the undivided attention of such a fine ship and so many highly trained men, it was an honour that K.15 would willingly have forgone.

What made the situation doubly annoying was the fact that his friends would be meeting him off Mars in about twelve hours, aboard a ship quite capable of dealing with a mere cruiser – from which you will gather that K.15 was a person of some importance. Unfortunately, the most optimistic calculation showed that the pursuers would be within accurate gun range in six hours. In some six hours five minutes, therefore, K.15 was likely to occupy an extensive and still expanding volume of space. There might just be time for him to land on Mars, but that would be one of the worst things he could do. It would certainly annoy the aggressively neutral Martians, and the political complications would be frightful. Moreover, if his friends
had
to come down to the planet to rescue him, it would cost them more than ten kilometres a second in fuel – most of their operational reserve.

He had only one advantage, and that a very dubious one. The commander of the cruiser might guess that he was heading for a rendezvous, but he would not know how close it was nor how large was the ship that was coming to meet him. If he could keep alive for only twelve hours, he would be safe. The ‘if’ was a somewhat considerable one.

K.15 looked moodily at his charts, wondering if it was worth while to burn the rest of his fuel in a final dash. But a dash to where? He would be completely helpless then, and the pursuing ship might still have enough in her tanks to catch him as he flashed outwards into the empty darkness, beyond all hope of rescue – passing his friends as they came sunwards at a relative speed so great that they could do nothing to save him.

With some people, the shorter the expectation of life, the more sluggish are the mental processes. They seem hypnotised by the approach of death, so resigned to their fate that they do nothing to avoid it. K.15, on the other hand, found that his mind worked better in such a desperate emergency. It began to work now as it had seldom done before.

Commander Smith – the name will do as well as any other – of the cruiser
Doradus
was not unduly surprised when K.15 began to decelerate. He had half-expected the spy to land on Mars, on the principle that internment was better than annihilation, but when the plotting-room brought the news that the little scout ship was heading for Phobos, he felt completely baffled. The inner moon was nothing but a jumble of rock some twenty kilometres across, and not even the economical Martians had ever found any use for it. K.15 must be pretty desperate if he thought it was going to be of any greater value to him.

The tiny scout had almost come to rest when the radar operator lost it against the mass of Phobos. During the braking manoeuvre, K.15 had squandered most of his lead and the
Doradus
was now only minutes away – though she was now beginning to decelerate lest she overrun him. The cruiser was scarcely three thousand kilometres from Phobos when she came to a complete halt: of K.15’s ship there was still no sign. It should be easily visible in the telescopes, but it was probably on the far side of the little moon.

It reappeared only a few minutes later, travelling under full thrust on a course directly away from the Sun. It was accelerating at almost five gravities – and it had broken its radio silence. An automatic recorder was broadcasting over and over again this interesting message:

‘I have landed on Phobos and am being attacked by a Z-class cruiser. Think I can hold out until you come, but hurry.’

The message wasn’t even in code, and it left Commander Smith a sorely puzzled man. The assumption that K.15 was still aboard the ship and that the whole thing was a ruse was just a little too naive. But it might be a double-bluff: the message had obviously been left in plain language so that he would receive it and be duly confused. He could afford neither the time nor the fuel to chase the scout if K.15 really had landed. It was clear that reinforcements were on the way and the sooner he left the vicinity the better. The phrase ‘Think I can hold out until you come’ might be a piece of sheer impertinence, or it might mean that help was very near indeed.

Then K.15’s ship stopped blasting. It had obviously exhausted its fuel, and was doing a little better than six kilometres a second away from the Sun. K.15
must
have landed, for his ship was now speeding helplessly out of the Solar System. Commander Smith didn’t like the message it was broadcasting, and guessed that it was running into the track of an approaching warship at some indefinite distance, but there was nothing to be done about that. The
Doradus
began to move towards Phobos, anxious to waste no time.

On the face of it, Commander Smith seemed the master of the situation. His ship was armed with a dozen heavy guided missiles and two turrets of electromagnetic guns. Against him was one man in a spacesuit, trapped on a moon only twenty kilometres across. It was not until Commander Smith had his first good look at Phobos, from a distance of less than a hundred kilometres, that he began to realise that, after all, K.15 might have a few cards up his sleeve.

To say that Phobos has a diameter of twenty kilometres, as the astronomy books invariably do, is highly misleading. The word ‘diameter’ implies a degree of symmetry which Phobos most certainly lacks. Like those other lumps of cosmic slag, the Asteroids, it is a shapeless mass of rock floating in space with, of course, no hint of an atmosphere and not much more gravity. It turns on its axis once every seven hours thirty-nine minutes, thus keeping the same face always to Mars – which is so close that appreciably less than half the planet is visible, the Poles being below the curve of the horizon. Beyond this, there is very little more to be said about Phobos.

*

K.15 had no time to enjoy the beauty of the crescent world filling the sky above him. He had thrown all the equipment he could carry out of the airlock, set the controls, and jumped. As the little ship went flaming out towards the stars he watched it go with feelings he did not care to analyse. He had burned his boats with a vengeance, and he could only hope that the oncoming battleship would intercept the radio message as the empty vessel went racing by into nothingness. There was also a faint possibility that the enemy cruiser might go in pursuit but that was rather too much to hope for.

He turned to examine his new home. The only light was the ochre radiance of Mars, since the Sun was below the horizon, but that was quite sufficient for his purpose and he could see very well. He stood in the centre of an irregular plain about two kilometres across, surrounded by low hills over which he could leap rather easily if he wished. There was a story he remembered reading long ago about a man who had accidentally jumped off Phobos: that wasn’t quite possible – though it was on Deimos – as the escape velocity was still about ten metres a second. But unless he was careful, he might easily find himself at such a height that it would take hours to fall back to the surface – and that would be fatal. For K.15’s plan was a simple one: he must remain as close to the surface of Phobos as possible –
and diametrically opposite the cruiser
. The
Doradus
could then fire all her armament against the twenty kilometres of rock, and he wouldn’t even feel the concussion. There were only two serious dangers, and one of these did not worry him greatly.

To the layman, knowing nothing of the finer details of astronautics, the plan would have seemed quite suicidal. The
Doradus
was armed with the latest in ultra-scientific weapons: moreover, the twenty kilometres which separated her from her prey represented less than a second’s flight at maximum speed. But Commander Smith knew better, and was already feeling rather unhappy. He realised, only too well, that of all the machines of transport man has ever invented, a cruiser of space is far and away the least manoeuvrable. It was a simple fact that K.15 could make half a dozen circuits of his little world while her commander was persuading the
Doradus
to do even one.

There is no need to go into technical details, but those who are still unconvinced might like to consider these elementary facts. A rocket-driven spaceship can, obviously, only accelerate along its major axis – that is, ‘forwards’. Any deviation from a straight course demands a physical turning of the ship, so that the motors can blast in another direction. Everyone knows that this is done by internal gyros or tangential steering jets: but very few people know just how long this simple manoeuvre takes. The average cruiser, fully fuelled, has a mass of two or three thousand tons, which does not make for rapid footwork. But things are even worse than this, for it is not the mass, but the moment of inertia that matters here – and since a cruiser is a long, thin object, its moment of inertia is slightly colossal. The sad fact remains (though it is seldom mentioned by astronautical engineers) that it takes a good ten minutes to rotate a spaceship through 180 degrees, with gyros of any reasonable size. Control jets are not much quicker, and in any case their use is restricted because the rotation they produce is permanent and they are liable to leave the ship spinning like a slow-motion pin-wheel, to the annoyance of all inside.