For a moment I stood beside the switch at the top of the

  stairs, wondering whether to throw it. Then I growled, "Shut up, Laika!" and flooded the place with light.

  She was scratching frantically at the door, pausing from time to time to give that hysterical yelp. "If you want out," I said angrily, "there's no need for all that fuss." I went down, shot the bolt, and she took off into the night like a rocket.

  It was very calm and still, with a waning Moon struggling to pierce the San Francisco fog. I stood in the luminous haze, looking out across the water to the lights of the city, waiting for Laika to come back so that I could chastise her suitably. I was still waiting when, for the second time in the twentieth century, the San Andreas Fault woke from its sleep.

  Oddly enough, I was not frightened—at first. I can remember that two thoughts passed through my mind, in the moment before I realized the danger. Surely, I told myself, the geophysicists could have given us some warning. And then I found myself thinking, with great surprise, "I'd no idea that earthquakes make so much noise!"

  It was about then that I knew that this was no ordinary quake; what happened afterward, I would prefer to forget. The Red Cross did not take me away until quite late the next morning, because I refused to leave Laika. As I looked at the shattered house containing the bodies of my friends, I knew that I owed my life to her; but the helicopter pilots could not be expected to understand that, and I cannot blame them for thinking that I was crazy, like so many of the others they had found wandering among the fires and the debris.

  After that, I do not suppose we were ever apart for more than a few hours. I have been told—and I can well believe it —that I became less and less interested in human company, without being actively unsocial or misanthropic. Between them, the stars and Laika filled all my needs. We used to go for long walks together over the mountains; it was the happiest time I have ever known. There was only one flaw; I knew, though Laika could not, how soon it must end.

  We had been planning the move for more than a decade. As far back as the nineteen-sixties it was realized that Earth

  was no place lor an astronomical observatory. Even the small pilot instruments on the Moon had far outperformed all the telescopes peering through the murk and haze of the terrestrial atmosphere. The story of Mount Wilson, Palomar, Greenwich, and the other great names was coming to an end; they would still be used for training purposes, but the research frontier must move out into space.

  I had to move with it; indeed, I had already been offered the post of Deputy Director, Farside Observatory. In a few months, I could hope to solve problems I had been working on for years. Beyond the atmosphere, I would be like a blind man who had suddenly been given sight.

  It was utterly impossible, of course, to take Laika with me. The only animals on the Moon were those needed for experimental purposes; it might be another generation before pets were allowed, and even then it would cost a fortune to carry them there—and to keep them alive. Providing Laika with her usual two pounds of meat a day would, I calculated, take several times my quite comfortable salary.

  The choice was simple and straightforward. I could stay on Earth and abandon my career. Or I could go to the Moon— and abandon Laika.

  After all, she was only a dog. In a dozen years, she would be dead, while I should be reaching the peak of my profession. No sane man would have hesitated over the matter; yet I did hesitate, and if by now you do not understand why, no further words of mine can help.

  In the end, I let matters go by default. Up to the very week I was due to leave, I had still made no plans for Laika. When Dr. Anderson volunteered to look after her, I accepted numbly, with scarcely a word of thanks. The old physicist and his wife had always been fond of her, and I am afraid that they considered me indifferent and heartless—when the truth was just the opposite. We went for one more walk together over the hills; then I delivered her silently to the Andersons, and did not see her again.

  Take-off was delayed almost twenty-four hours, until a

  major flare storm had cleared the Earth's orbit; even so, the Van Allen belts were still so active that we had to make our exit through the North Polar Gap. It was a miserable flight; apart from the usual trouble with weightlessness, we were all groggy with antiradiation drugs. The ship was already over Farside before I took much interest in the proceedings, so I missed the sight of Earth dropping below the horizon. Nor was I really sorry; I wanted no reminders, and intended to think only of the future. Yet I could not shake off that feeling of guilt; I had deserted someone who loved and trusted me, and was no better than those who had abandoned Laika when she was a puppy, beside the dusty road to Palomar.

  The news that she was dead reached me a month later. There was no reason that anyone knew; the Andersons had done their best, and were very upset. She had just lost interest in living, it seemed. For a while, I think I did the same; but work is a wonderful anodyne, and my program was just getting under way. Though I never forgot Laika, in a little while the memory ceased to hurt.

  Then why had it come back to haunt me, five years later, on the far side of the Moon? I was searching my mind for the reason when the metal building around me quivered as if under the impact of a heavy blow. I reacted without thinking, and was already closing the helmet of my emergency suit when the foundations slipped and the wall tore open with a short-lived scream of escaping air. Because I had automatically pressed the General Alarm button, we lost only two men, despite the fact that the tremor—the worst ever recorded on Farside—cracked all three of the Observatory's pressure domes.

  It is hardly necessary for me to say that I do not believe in the supernatural; everything that happened has a perfectly rational explanation, obvious to any man with the slightest knowledge of psychology. In the second San Francisco earthquake, Laika was not the only dog to sense approaching disaster; many such cases were reported. And on Farside, my own memories must have given me that height-

  ened awareness, when my never-sleeping subconscious detected the first faint vibrations from within the Moon.

  The human mind has strange and labyrinthine ways of going about its business; it knew the signal that would most swiftly rouse me to the knowledge of danger. There is nothing more to it than that; though in a sense one could say that Laika woke me on both occasions, there is no mystery about it, no miraculous warning across the gulf that neither man nor dog can ever bridge.

  Of that I am sure, if I am sure of anything. Yet sometimes I wake now, in the silence of the Moon, and wish that the dream could have lasted a few seconds longer—so that I could have looked just once more into those luminous brown eyes, brimming with an unselfish, undemanding love I have found nowhere else on this or on any other world.

  Colombo April 1961

  Hide and Seek

  We were walking back through the woods when Kingman saw the gray 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 gray. 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 leveled 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 squirr
els), "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 gray 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 kilometers sunward 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 enemy 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 honor 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 kilometers 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 or 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 worthwhile 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 outward into the empty darkness, beyond all hope of rescue—passing his friends as they came sunward 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 hypnotized 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 kilometers 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 maneuver, 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 kilometers 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, traveling 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 kilometers 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 toward 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 space suit, trapped on a moon only twenty kilometers across. It was not until Commander Smith had his first good look at Phobos, from a distance of less than a hundred kilometers, that he began to realize that, after all, K.15 might have a few cards up his sleeve.

  To say that Phobos has a diameter of twenty kilometers, 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 air lock, set the controls, and jumped. As the little ship went flaming out toward the stars he watched it go with feelings he did not care to analyze. 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 ocher 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 center of an irregular plain about two kilometers 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—because the escape velocity was still about ten meters 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.l5'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 kilometers of rock, and he wouldn't even feel th
e 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 ultrascientific weapons: moreover, the twenty kilometers 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 realized, only too well, that of all the machines of transport man has ever invented, a cruiser of space is far and away the least maneuverable. 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 make 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, "forward." 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 maneuver takes. The average cruiser, fully fueled, 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 isn't 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 one hundred and eighty degrees, with gyros of any reasonable size. Control jets aren't 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 pinwheel, to the annoyance of all inside.

  In the ordinary way, these disadvantages are not very grave. One has millions of kilometers and hundreds of hours in which to deal with such minor matters as a change in the ship's orientation. It is definitely against the rules to move in ten-kilometer-radius circles, and the commander of the Doradus felt distinctly aggrieved. K.15 wasn't playing fair.