by Hal Clement
It would not be possible to maintain a watch from the Hunter’s present position, and at the same time send himself under the sand to a point below the motionless body; and he must keep his goal in sight. Once more camouflage seemed called for; and once more, the ever-present jellyfish seemed to fill the want. There were a number of them lying stranded on the sand, motionless; perhaps, if he moved slowly and emulated their shape, the Hunter could escape notice until he was close enough for an underground attack.
He may have been excessively cautious, since none of the creatures was facing his way and all were nearly if not entirely asleep; but caution is never wasted, and the Hunter never regretted the twenty minutes he took getting from the water’s edge to a point three yards from Robert Kinnaird. That, judging by the previous experience, was close to enough.
Had anyone been watching the large jellyfish lying apparently helpless a few feet from the boy at that instant, he might have noticed a peculiar dimunition in its size. The shrinking itself was not remarkable; ‘it is the inevitable fate of a jellyfish on a hot beach; but the more orthodox Medusae merely grow thinner until only a Cobwebby skeleton remains, while this specimen dwindled not only in thickness but in diameter, and there were no remains whatever. Until it had almost completely gone, of course, there was an odd little lump or knot right in the center which preserved its size and—shape while the body around it dwindled; but this at last went too, and no trace except a slight depression remained on the sand—a depression which, that careful observer might have noticed, extended all the way from the water’s edge.
The Hunter kept the eye in use during most of the underground search. His questing appendage at last reached sand that was more closely compacted than usual and, advancing now very cautiously, finally, encountered what could only be living flesh. Robert’s toes had become rather deeply buried in the sand, as he was lying on his stomach; and the Hunter found that he could operate without emerging at all to the surface. With that fact established, he dissolved the eye, and drew the last of his mass out of sight below the sand—with considerable relief, as the unobstructed sunlight affected his unprotected tissues painfully.
He did not attempt to penetrate until his whole body was wrapped about the half-buried foot. He surrounded the limb with extreme care, and finally was in direct contact with the skin over an area of several square inches. Then he commenced interstition, letting the submicroscopic cells of his flesh slide through pores, between cells, under arid around the toenails—into all the thousands of openings that lay unguarded in this, to his way of thinking, singularly coarse organism.
The boy was sound asleep, and remained so. The alien organism flowed smoothly along the bones and tendons in his foot and ankle; up within the muscle sheaths of calf and thigh; switched to the outer wall of the femoral artery and the tubelets within the structure of the thigh bones; around points, and along still other blood vessels. It filtered through the peritoneum without causing the least damage; and slowly the whole four pounds of matter accumulated in the abdominal cavity, not only without harming the boy in the least but without even disturbing his slumber. And there, for a few minutes, the Hunter rested.
Bob was aroused, like the other boys, by his mother’s voice. She had come silently, laid a blanket in the shade, and spread the eatables on it before speaking; and her first words were the ancient, “Come and get it,” which have stimulated boys and men to sometimes startling activity for a good many decades. She would not stay to help them eat it, though cordially and sincerely pressed to do so by the boys, with whom she was popular, but went back through the palm grove to the road that led to their home.
“Try to be back by sundown,” she called to Bob over her shoulder as she reached the trees, “you still have to pack, and you’ll have to be up early in the morning.” Bob nodded, with his mouth full, and turned back to the food-laden blanket.
After disposing of that which lay before them, the boys sat and talked for the standard hour-after-eating; then they returned to the water, where they indulged further in games of violence; and at last, realizing that the abrupt tropical night would soon be upon them, they gathered up the blanket and started for the road and their respective dwellings. They were rather silent, with the, awkwardness natural to their age when faced by a situation which adults would treat either emotionally or with studied casualness. The farewells, as they passed their respective dwellings, were brief, and accompanied by reiterated and reciprocated promises to “write as soon as you can.”
Bob, proceeding at last alone to his own house, felt the customary mixture of regret and pleasurable anticipation which he had come to associate with these occasions. By the time he reached home, the latter feeling had gained the ascendance, and he was looking forward with considerable eagerness to meeting again the school friends he had not seen for over two months. He was whistling cheerfully as he entered the house.
The packing, done with the tactful assistance of his mother, was quickly completed, and by nine o’clock he was in bed and asleep. He himself considered the hour rather early, but he had learned the value of obedience at certain times very early in life.
All this time the Hunter had remained quiescent. Having entered from air rather than water, he had been able to bring quite a supply of oxygen with him; and it was some hours before he found it needful to draw on his host for more. He would have liked to remain inactive for an entire day, in order to learn more about the cycle of physiological processes which this organism undoubtedly performed differently from any other he had ever used; but that was not possible. Like any other life form, he used some energy in living, no matter how quietly; and at last he found it necessary to commence exploration.
For some time he had been aware that his host was asleep; but this in no way decreased his caution. He remained for the time being below the diaphragm, not wishing to disturb the heart which he could feel beating just above it, and quickly located a very large artery which offered no more resistance to his penetration than had any other part of the human organism thus far. He found to his intense satisfaction that he could draw sufficient oxygen for his needs from this vessel without seriously diminishing the total quantity that passed through it. He checked this very carefully; his whole attitude in the present exploration was utterly different from that which had characterized his actions within the shark; for he had already come to look upon Robert in the light of a permanent companion during his stay on the earth, and his actions were ruled by a law of his kind so ancient and so rigid as to assume almost the proportions of an instinct.
Do nothing that can harm your host. It was a law as binding as the Hippocratic oath or a marriage vow. To the majority of the Hunter’s kind, even the desire to break it never existed, since they lived on terms of the warmest friendship with the intelligent metazoans who harbored their formless bodies; and the few individuals who proved to be exceptions to this rule were looked on by their fellows with the liveliest horror and detestation. It was such a being whom the Hunter had been pursuing at the time of his crash on Earth; and that being must still be found, to preserve a defenseless race from the inroads of the irresponsible creature.
Do nothing that can harm your host. From the instant of the Hunter’s arrival, the swarming leucocytes in the boy’s healthy blood had been up in arms. He had avoided the most serious contact with them up to now by avoiding the interiors of blood vessels, though there were enough of them wandering free in the lymphatics and connective tissue to be a nuisance. His body cells were not immune to their powers of absorption, and only by keeping any part exposed to their attack in constant evasive motion had he been able to avoid, serious damage to himself. He knew that this could not go on indefinitely; for one thing, he must occasionally direct his attention to other matters, and for another, the continuation of such a misunderstanding, whether he continued evasive action or began to fight back, would mean an increase in white blood cell concentration and most probably illness of some sort to ‘the host. Theref
ore, the leucocytes must be pacified. His race had, of course, acquired a general technique for solving this problem long since; but care had to be taken in individual cases—particularly unfamiliar ones. By a trial-and-error process, carried out with as much speed as was practical, the Hunter determined the nature of the chemical clues by which the white cells differentiated invading organisms from legitimate members of the human body; and after prolonged and still extremely careful effort, he exposed every one of his own cells to sources of the appropriate chemicals in the blood stream. A few molecules of the desired substance were adsorbed on the surface of each of the cells, and this proved, to his relief, to be sufficient. The leucocytes ceased to bother him, and he could use the larger blood vessels safely as avenues of exploration for his questing pseudopodia.
Do nothing that can harm your host. He needed food as well as oxygen. There was not a single form of tissue around him which he could not have consumed with relish; hut selection must obviously be practiced. There were certainly intruding organisms in this body—besides himself—and they were the natural food source; for by consuming them he would be eliminating their menace to his host, and thereby helping earn his keep. Identifying them would be easy; anything a leucocyte attacked was legitimate prey for him. It was improbable, of course, that this source of food would prove adequate for long, small as his needs were; it would soon be necessary to tap the alimentary canal as well. That, however, would be simple and would in no way harm the boy. His appetite might be increased very slightly over a long period, but a little additional chewing was no cause for alarm.
For many hours the cautious exploration and adjustment continued. The Hunter felt his host awaken and resume activity, but he made as yet no effort to look outside. He had one problem which must be carefully and accurately solved; and, although his avoiding thousands of leucocytes at once, as he had done for a time, may seem evidence to the contrary, his powers of attention were limited. Filaments of his mass, far finer than human neurons, gradually formed an all-inclusive network throughout Bob’s body from head to toe; and through those threads the Hunter gradually came to know the purpose and customary uses of every muscle, gland, and sense organ in that body. Throughout this period most of his mass remained in the abdominal cavity; and it was fully seventy-two hours after his first intrusion that the alien felt secure enough in his position to pay attention once more to outside affairs.
As he had done with the shark, he began to fill the spaces between the boy’s retinal cells with his own body substance. He was actually able to make better use of the eyes than could Bob himself, for the human eye sees in maximum detail only the objects whose images fall within an area of retina scarcely a millimeter across; the Hunter could use the whole area on which the lens focused with reasonable sharpness, which was considerably greater. In consequence, he could examine objects with Bob’s eyes at which the boy was not looking directly. This was a help, since many of the things in which the hidden searcher was most interested were too commonplace to the human being to attract more than momentary attention.
The Hunter could hear dimly even within the human body; but he found it helpful to establish physical contact with the bones of the middle ear. Thus, hearing as well and seeing better than his host, he felt ready to investigate the planet on which chance had marooned him and his quarry. He began to look and listen. There was no further reason for delay in prosecuting his mission to track down and destroy the other member of his race now free on the planet.
He had not, up to this moment, really appreciated the magnitude of the task. He had not considered particularly the fact that the other might be as welt hidden as was he himself, that the planet represented an enormous search area however small it might be as planets went, and that even a very small population of possible hosts meant a most appalling amount of search work even if he could recognize the presence of the alien at sight—which he most certainly could not.
All these facts were brought to his attention with shocking suddenness as he took his first clear look around since meeting Robert Kinnaird. The picture that fell on their common retinas was that of the interior of a cylindrical object that vaguely suggested his own spaceship, filled with several rows of seats, most of them occupied by other human beings. Beside him was a window, through which Bob was looking at the moment; and the suspicion that had entered the Hunter’s mind at sight of the vehicle was instantly confirmed by the view through that window. They were on board an aircraft, traveling at a considerable altitude with a, speed and in a direction which the Hunter was in no position to guess. He had hoped at least to begin his search in a region of the crash of the two spaceships; now he realized he would be extremely fortunate even to find that region.
The flight lasted for several hours, and the Hunter quickly gave up the attempt to memorize landmarks-over which they passed. One or two of them did stick in his mind, and might give a rough clue to direction if he could ever identify them later; but he put little trust in this chance. He must keep track of time rather than position, and when he was more familiar with human ways, find out where his host had been at the time of his own intrusion.
The view was interesting, however. It was a beautiful planet, even from his alien viewpoint; mountains and plains, rivers and lakes, forests and prairies were all visible at various times, now clearly through a crystal atmosphere and now in glimpses between billowing clouds of water vapor. The machine he rode occupied some of his attention, as well; from Robert’s window he could see a portion of a metal wing, bearing at least one attachment which evidently contained an engine, as a rapidly rotating airfoil was visible ahead of it. By symmetry, there must be at least two and possibly four of these engines, the Hunter realized; and the machine, as a whole, suggested a very considerable degree of mechanical advancement on the part of this race. If this were the case, it might be worth while to attempt direct communication with the individual serving as his host. That, however, must await further developments.
Eventually the machine began to descend gradually. The Hunter could not see directly ahead, and it happened that they entered a solid cloud layer almost immediately, so he was unable to get any idea of their destination until just before the landing; but at that moment, as they broke out of the lower fringe ‘ of clouds, they made a broad turn over a large seaport city. The Hunter saw a great harbor, with decks and shipping galore, and buildings that reached as far as he could see; then the faint drone of the engines that penetrated the airplane’s cabin increased in pitch, a huge wheel appeared below the visible nacelle, and the big machine glided downwards to contact with a faint jar a broad, hard-surfaced runway located on a point of land across the harbor from the city’s largest buildings.
As Robert disembarked, he glanced back at the airplane; so the Hunter was able to form a better estimate of its size and construction details. He had no idea of the power developed by the four huge engines, and consequently could form no estimate of the machine’s speed; but he could see the quivering above the nacelles that told of hot metal within, and realized that at least they were not the phoenix converters most familiar to his own civilization. Whatever they were, it had already become evident that the craft could put a very respectable fraction of the planet’s circumference behind it without descending for fuel.
After alighting from the airplane, the boy entered a large building nearby, which was crowded with other human beings, and waited for a time. Presently he made his way through the throng to a broad counter, and received his baggage, which be bore off to the other end of the building where a number of ground vehicles were standing. He boarded one of these, which remained where it was until nearly full of passengers, and then moved off toward the denser portion of the city.
During the next several hours, the boy’s actions were largely meaningless to his hidden guest. He changed buses several times, wandered about the city on foot for a while with no apparent purpose, and attended a movie. Fortunately the Hunter’s vision persistence involved a ti
me lapse of approximately the same duration as the human retina, so he also saw moving pictures rather than discrete projections. It was still daylight when they left the theater, and the Hunter decided that it must have been fairly early in the morning when he had first established visual connection with the outside world.
Now his host was walking with what seemed to be a purpose. They returned to a building where they had been earlier, where Robert once more collected his bags; then, after the ticket-window preliminaries which the Hunter was beginning to recognize as customary before a ride, they boarded still another bus. This was decidedly the longest single ride they had taken since leaving the airplane; they were well outside the city, having passed through several smaller collections of buildings, and the sun was almost down when the bus left them at the roadside.
A smaller road led off up a gentle slope; and at the top of this slope was a large, sprawling building—or group of buildings; the Hunter was not sure which. Robert Kinnaird picked up his bags and walked up the hill toward the structure, and the alien began to hope that the journey had ended for the time being at least. He was right, as it turned out.
To Robert, the return to school, assignment to a room, and meeting with old acquaintances was by now a familiar story; but to the Hunter every activity and everything seen and heard was of absorbing interest. He realized that most of it could have no direct application to his mission, but that was no reason to ignore possible sources of knowledge. He was a being of omnivorous interests, and was beginning to realize that direct communication with the human race was going to be necessary. That meant understanding them and their customs, preparatory to learning their spoken and written languages.
So he looked and listened almost feverishly, as Bob went to his room, unpacked, and then wandered about the school meeting friends from former terms. Most particularly he sought to connect spoken words with their meanings; and at first he had a good deal of trouble, for the conversations were mostly about events of the past two months vacation, so that the words usually lacked visible referents. He did learn a few personal names this first evening, among them that of his host, and decided that he could acquire an understanding of the spoken language with little loss of time.