CHAPTER XII. DISCOPHORA, by A. Keith Borrowdale being a transcription of a new theory, by Dr. Andrew McGillivray

LOOKING BACK on our adventure, now that all is done, the scene I recollect as most unreal, somehow, in the whole long dreamlike sequence of our story’s tragic climax, is that in the trailer a mile or more from the great menacing bulk of the Ridge.

We had come to rest there, at a distance judged by Dr. Kalkenbrenner to be relatively safe, if only for a moment or two. We knew, from what we had heard of the Cloud—from what we had seen of it within the forest itself—that it could sweep across the intervening desert in a matter of seconds to encompass us. We had half expected, indeed, that it would pursue us—would swirl about us as we traveled, impotent though it was to harm us through the treated materials of our coverings. But the air was clear and bright as we went forward; and when we did halt and peered back toward the forest, it was to see no more than a lingering yellow nimbus in the atmosphere above it. The long stretch of the Ridge was silent again, the massive fronds swaying slightly as if in a gentle breeze, although on that whole vast plain there was no breeze.

So we halted, and set to reviving the two unconscious men we had carried so strangely with us. We were able to breathe freely now, through the air valves in our helmets—yet, on Dr. Kalkenbrenner’s strict command, were prepared at a second’s notice to reconnect the oxygen apparatus and retire to shelter if we should see any sign of attack.

At one moment, as we toiled, it was as if danger did loom. There was a cry from Paul and we saw his pointing arm outflung along the line of the Ridge’s long straight “tail.” Far, far to the south and west (as we calculated it in later recollection), an immense convulsion seemed to shake the straight forest wall; and out across the sky, at a terrifying velocity even at so remote a distance, there went a great yellow arrowhead, as it were, of the poisonous mist. It seemed for an instant to writhe toward us, and we prepared our defenses; but then it turned and swept obliquely across our path, a seething and awesome spectacle, the vast Cloud itself in full flight, as McGillivray and MacFarlane must have seen it at the moment of their landing—as, imperfectly, it has been glimpsed and recorded in motion across the far-off Martian surface by terrestrial astronomers: as we have veritably seen it ourselves since our return, through Earth’s most powerful telescopes.[5]

We worked on, transferring our helpless comrades to the trailer and fitting them with suits and helmets like our own. And there enclosed, when weakly they spoke to us as their own true selves at last after all their nightmare experiences, we heard the truth—as much of the truth as could be deduced from what MacFarlane had seen and McGillivray and Malu had instinctively comprehended.

A mile away, in the green depths of the Ridge, were Katey, Maggie and the indomitable Michael. Our deepest desire was to help them—somehow to help them, if it was not too late for any help. But it was only wise, as our leader quietly assured us, to know something at least of our enemy’s nature before we made any further efforts toward rescue.

So we lingered then, in the last long lull before the climax: we lingered there on the plain, in silence, confronting the two men who had suffered so much since they had set out across limitless space in search of adventure on the Angry Planet—and, most bitterly, had found it. They spoke hesitantly, almost incoherently at the outset, until they were able, after so long, to marshal their troubled thoughts. I cannot attempt to reproduce their conversation in its original form, and so I transcribe here only a continuous version of it. If it seems that we lingered unduly with our companions in such danger to hear the history of the Vivores, reflect that that is partly due to the way in which I must set down the facts on paper. In its actual progress the scene in the trailer took little time enough. But reflect also on the wisdom of Dr. Kalkenbrenner’s utterance—that it was indeed well for us to learn something of our enemy’s nature; otherwise, as I must assure you, our own tragic attempt at escape might never have been possible.

And even the facts, as I array them here, are imperfect and fragmentary: we still know little enough, in all conscience, of the true nature of the Creeping Canals—Discophora remains a half-glimpsed nightmare to all of us; and will continue so until, with the help of Providence, we once more set out on a voyage of scientific discovery. . . .

“They control,” began Dr. McGillivray. “These creatures can control. They controlled us, against every instinct in us. They made us welcome you as we did, with no hint of danger to you. We tried—God knows we tried to warn you! But we were bewitched—the old word is the best one. We were possessed by them—the Martian telepathic principle was carried to its last conclusion.”

“Yet you broke the spell at last,” said Kalkenbrenner quietly—and I saw that he realized to the full, from his own instinctive guess at the nature of the enemy, exactly how much effort of will power it had cost.

McGillivray nodded and smiled a little ruefully, his blind eyes turned slightly away.

“We had to. We simply had to. I fought with every ounce of control until I could make that one short speech as myself and tell you to pay no heed to all we had said, to restrain us somehow, to bind us—destroy us if necessary.”

“As the good Archie Borrowdale almost did,” said MacFarlane, also with a rueful smile, fingering a bruise on his jaw where I had been compelled to strike him. “Still, it was the only way—and there are no hard feelings, Borrowdale—and no fear of a return bout, I hope! They had me even worse than they had the Doctor. I managed to get the door shut, so that they couldn’t send in that devilish Cloud; but it was all I could do—they had me again a moment later and made me attack you, until you mercifully knocked me out. Thank heaven you did—otherwise, if I’d had a chance, I’d have opened the door again—that was what they wanted to make me do. You would have been all right, in those suits of yours, but it might have been the end after all for poor old Mac and me. . . .”

“We had no remote suggestion during the first trip that there were such creatures,” McGillivray continued. “You young people know that—we met only the Beautiful People and the Terrible Ones. Malu has told me that far back in Martian history, as it has been remembered by such rulers as himself and the Center, there were shadowy legends and recollections of the Creeping Canals, the deadly long lines of them spreading across the planet’s surface; and that in the Canals were creatures of some kind, even stronger in their power of enmity than the Terrible Ones. The Terrible Ones were enemies indeed—we also know that; but they were plants like the Beautiful People themselves, and could be dealt with in combat—could be hacked and destroyed by means of the long silica swords perfected by Malu and his friends. These other beings were different altogether: they caused no physical harm to the plant-folk—but they enslaved them mentally. That is why, long, long ago, the various groups of the Beautiful People tended to migrate northward and, without ever fully knowing why, to confine themselves to certain well-defined tracts of territory. The legendary Canal Creatures were known to concentrate mainly in the south, once they had made their initial journeys from the polar caps, as I shall explain later. But you see, when the volcano destroyed Malu’s settlement, at the end of our first Martian visit, his people were forced to travel, as we told you in the messages; and they traveled south, farther and farther south, in search of uninhabited bubble houses. What they did not fully understand, until almost too late, was that the bubble houses they did eventually find were empty only because they bordered on one of the deadly Canal zones.”

“But they escaped?” said Paul, half-questioningly. And it was Malu who answered—the “voice” came into my head as he reclined strangely in the trailer with us, close to Jacqueline.

“My people went north as the great Canal crept forward toward the hills and the spaceship,” he said. “It was better so, in order to preserve our young ones. Where they are I know not—except that I have understood, from the plain plants, that they are far away and in safety. I alone remained to help my friends; for the people you know as Discophora are not able to control such as Malu, Prince of the Beautiful People, in so great a measure as they can control such as you from across the skies.”

“It’s true indeed,” nodded McGillivray. “They can control Malu, of course—they can control the Beautiful People just as you saw they had controlled a group of the Terrible Ones, to act as their slaves or soldiers, as it were; but to nothing like the extent they can control us—and for a very good reason, as you shall hear. It meant that they forced us to lock Malu up when you were approaching. With him concealed in that way, they were able to influence him just sufficiently for his thoughts not to reach you. It was when Jacky suddenly and intensely thought of Malu in the Albatross that his thoughts were able to break through, and so gave me the strength to speak. . . . It seems so strange—so complex a mechanism, and difficult indeed to explain. You must only take it that that is how the influence of these creatures operates. Someday we may know more about them and so be able to comprehend how their telepathic impulses do work in practice. In the meantime, as far as Discophora is concerned—” It was Paul, the practical Paul, who interrupted quietly at this stage, to ask the question which indeed engaged us all—which had lain behind all other questions as the great jigsaw fitted together.

“In the meantime, sir,” he said, leaning forward a little toward the sightless man, “what is Discophora? What are the Creeping Canals?”

Dr. McGillivray hesitated for a long, long moment before he replied.

“In a word—” he said very gravely, “in a word, boy, and in so far as I understand the great inscrutable mystery of Martian nature, they are . . . Survivors!”

And on the instant, in my own questing mind, one more small fragment of the jigsaw fitted. Again I remembered the airstrip messages—the first, the only occasion, on which MacFarlane had tried to tell us something of the nature of the enemy attacking the Albatross. I remembered the distorted reception that night—how, imperfectly, we had picked on one word and had used it ever afterward, ourselves, to describe the whole phenomenon. The Vivores! That one word, so compelling and mysterious—so suggestive indeed of living beings vastly, vastly different from ourselves in all their aspects. The Vivores . . . ! The imperfect translation, amid the interference, of the word which had truly been sent to us across space: the Survivors!

And Dr. Kalkenbrenner, himself after all a scientist, his mind operating along the same lines as McGillivray’s, nodded seriously.

“Yes—yes,” he said. “I guessed—I almost guessed. I had a notion from the start, but too instinctive and shadowy a notion to warrant expression. Survivors . . . from the ancient days of Martian prehistory—”

“When there was indeed an animal as well as a plant life upon the planet,” went on McGillivray. “We knew, even on the last trip, that it must have been so, thousands, possibly millions of years ago. We knew that the Terrible Ones were descendants of a species of plant, like our insect-eating plants on Earth, which had lived on flesh. . . . Someday, long, long ago, there must have been animal life to provide the forebears of the Terrible Ones with such food. As the countless ages went on, it died away, this animal life—as the reptiles died on Earth, the great hordes of the diplodoci, the pterodactyls, the dinosaurs. All, all perished—evolved to a point of development where they became extinct. The plants like the Terrible Ones adjusted themselves to the new conditions—contrived a method of survival which made them independent. . . . I merely sketch it all, of course—I cover, in these few words, a million years and more. I only speculate that indeed it happened—although there is, as I see it, no other possible answer to Discophora.”

“And what were these . . . animals who once lived on Mars?” asked Jacky hesitantly. “What were they like, sir?”

“Some of them, I believe,” said McGillivray slowly, “some of them, my dear, were very like ourselves. Perhaps not in physical appearance, although that too is possible; but at least in that they had brains—most powerful brains. It was long ago, long, long ago. What I tell you now is only a gigantic guess I have made, I sketch a mighty vision I have had; but I feel it to be near the truth, and I see it thus:

“There were, in those far times, among all other animals on Mars, some animals as highly civilized as we are upon Earth. What the nature of that civilization was it is impossible to say—there may be traces of it somewhere, somewhere: we shall someday see. But these beings, whatever they looked like, had intelligence to a high degree. They evolved, as the centuries went on—as we on Earth evolved as our centuries went on. They, however, developed their intelligences to a pitch where their bodies shrank and dwindled, where their nobler feelings, if they had ever had any, decayed and died. They became thinkers—only thinkers. The power of their brains was such that they could control all other sentient beings near to them. But their bodies were so emaciated, as the centuries marched past, that in a purely physical way they could hardly survive. They fell victim to creatures stronger than themselves, despite the power of their brains. They solved a million problems by thinking—and at last, and inevitably, they solved this one. Do not necessarily believe what I say—only take it as a speculation; but reflect whether there is any other answer to the problems with which we are now confronted.

“You know that as Mars, as the very planet itself began to die, there was an inevitable drying up of the surface. Moisture grew scarce and scarcer—and moisture is necessary for the survival of animal life. The plants solved the problem by developing as our terrestrial cacti have developed—with fleshy leaves and long, long tuberous roots, capable of finding sparse moisture in the depths of the desert soil. Malu and his people feed through these cactus plants, as we know. But for animal life there was no hope without more moisture than that; and so the creatures we know as the Discophora—those few who had survived all other ravages of nature—had to turn their great intelligences toward this single vital issue.

“In the centuries long gone by, when Mars was as lush, as fertile, as tropical Earth is, there was, as I conceive it, a species of gigantic marsh plants, rich and fecund—something equivalent, I should fancy, to our homely alisma plantago.” (He smiled for a moment at his own incurable habit of using Latin names for common objects.) “These massive water-plantains, as tall as trees upon Earth, came under the cultural control of the last intelligent survivors of Martian animal life. You will know how we, in our human way, have cultivated many plants for our own vital purposes—have evolved the useful cabbage from the small ornamental cliff plant brassica, for an example. In similar ways, the old Martians cultivated alisma plantago. They developed two characteristics of the plant to fantastic extents: first, its ability to find moisture; second, its extraordinary reproductive capacity. In its natural state alisma, as we might call it for brevity, reproduced itself at the speed of our own little garden plant known as mother-of-millions. Under the guidance of the Martians, this ability was intensified even further: the yellow seeds, or spores, of the plant were multiplied by careful selective breeding—the plant itself was trained to eject these spores in cloudy millions. More—more than that even. Alisma, like all Martian plants, was equipped with crude thinking abilities. It was a simple enough matter for the old Martians, with their powerful intelligences, to control the activities of primitive alisma; and this had several results. As the years went on, not only did the Martians produce a blend, as I might call it, of flying spores which were not only seeds but tiny stinging cells, as a protection no doubt against any other surviving animal life at the time, but they also equipped these very seeds with some small intelligence—not in their own right, but so that they could carry messages for the Martians themselves as they sped through the air . . . !

“Time passed and time passed. The moisture upon the Martian surface grew scarcer still. Yet, as you yourselves know, for you have seen them, there are two gigantic fields on Mars where moisture still exists in comparative abundance; and those are the two white polar caps, as we all observed them in our approach to the planet—as they can be observed even from Earth through powerful enough telescopes. Ice—or at least a heavy hoarfrost—exists on and near the two poles. And so the last survivors of the old Martians solved their final problem. By this time, as I believe, they themselves had evolved further—were physically almost helpless, so mightily had their actual intelligences developed. There were probably very few of them; but among all other problems solved was surely that also of longevity—those few were capable of survival for long, long years, even centuries perhaps, if once they could find warmth, moisture and a means of movement. They found all three—with the unwitting help of the cultivated alisma plants.

“They concentrated on the poles—and mainly, for some reason impossible as yet to guess, on the southern pole. There, for a space, as I see it in my vision, they reared huge colonies, huge nurseries of alisma. And from there, in a gigantic network over the entire Martian surface, they traveled!

“Yes—traveled! I have spoken of the power of alisma to reproduce its kind at a speed inconceivable to any plant, wild or cultivated, upon Earth. That, then, is how the few remaining survivors of those old animal Martians move—in the midst of what we have called the Creeping Canals, those immense green channels seen by Schiaparelli and Lowell. They are borne forward in any direction in which they wish to travel by the crowded ranks of the gigantic alisma—the Ridge plants. With them, as they go, they carry—literally manufacture in vast morasses around alisma’s thirsty roots—the moisture they need for survival. As for warmth, the warmth which is evident in the steamy vapor you have seen in the heart of the Canals themselves, that problem too has been solved. If alisma sprouts at fabulous speed, so also does it die and decay at fabulous speed; and in decay lies warmth!

“In their traveling dens the remaining Survivors of that ancient intelligent race still lurk. They push forward across the plains in any direction they may choose. Progress is maintained by an advance guard, as it were, of sprouting alisma; behind, the long forest consolidates itself—forms a marshy bed for the Survivors, warm and dank as the expended Ridge plants die. From time to time, the Survivors communicate with each other across the desert spaces by causing alisma to ejaculate great clouds of the messenger spores—which also act as spies, as it were, to bring back news of any unusual objects encountered on the flight—objects such as ourselves in the Albatross, toward which the particular Creeping Canal out there immediately directed its track of advance. From Canal to Canal these myriad yellow messengers travel to and fro. Within each Canal, as I am convinced, there lives one—only one—of the Survivors; an intelligence controlling all things within its deadly range. They are not evil—not truly evil, as we conceive it; it is only, I believe, that in their long struggle for existence, those intelligences, once perhaps noble, are concerned now not with worthy thoughts, but with thoughts only for further survival in their extreme age. All things are subordinated to that—all objects encountered are considered only in relation to that: how can they help the Survivors still to survive? And it has become more imperative than ever that they should survive, these Vivores, as you call them; for now they are old and must find some method to replace themselves—to renew themselves. That is the final horror. And that is why—” he paused and sighed profoundly, “why you, my dears, are here!”

Silence—a long, long silence. The gigantic vision filled me. It was fabulous—impossible; yet it was the truth—I knew it for the truth as I looked out through the little kalspex window to the silent forest of the Ridge plants—of the alisma, as McGillivray had called them. Somewhere within it, in addition to our own lost friends, was . . . what? One single Survivor—one of the terrible Vivores indeed. I recalled the white jellyish nightmare I had glimpsed in the forest’s deep heart: was that huge shapeless mass the very creature?

The question was asked—and answered—the moment I had formulated it.

“And the Survivors themselves?” asked Dr. Kalkenbrenner very quietly in the silence. “They are, I take it, from your descriptions, from the messages you sent us—”

Dr. McGillivray held up a hand to arrest the question, smiling sadly.

“When I myself was immersed in the Cloud,” he said, “there was communicated to me, from that swirling horror, even as it stung me to insensibility, a vision of its master. As MacFarlane has told you, as I gradually came back to life, this vision haunted me. The creature—as you yourselves now know—is white and jellyish indeed. It had stung me almost to death. In my confusion of mind it was likened to the only creature I knew upon earth to be jellyish and to sting: Discophora.”

“The jellyfish,” cried Paul, jumping to his feet in his excitement. “We looked it up in the dictionary too. Discophora does mean jellyfish! A huge jellyfish! Is that what the Vivores are, sir?—monstrous jellyfish?”

McGillivray paused once more. His eyes, for all their blindness, seemed for a moment to penetrate deeply into the far-off forest. His voice was barely more than a whisper. “Monstrous—yes. And jellyish—yes. But in no other respect does this white nightmare resemble our true Discophora after all. That great pulsating mass you saw—which I saw, in the days when I could see, if only with my inner eye—that bodiless Survivor of a race once splendid, is one thing and one thing only: a gigantic and decaying BRAIN!”

I thrilled with horror indeed—with a sudden horror unspeakable. I looked at the tense, set faces of my companions in the trailer tent, and saw reflected in them my own profound revulsion. I understood now, at last, the true power of the deadly Vivores—why it was that they could control other intelligences, and particularly human intelligences: because they themselves were truly nothing other than Intelligences, immobile and raw. . . .

A thousand other questions answered themselves in the few quiet moments remaining before the last piling climax to all the adventure. Now once more I find myself confused as I look back, for many things indeed happened almost instantaneously. I remember first, however, after our initial stunned silence, a host of rapid questions and answers.

“But the messages, sir? Why did you send the messages for us to come? You said we had to come—that we were the only ones who could save you. Yet how? Of course we’d want to try to save you; but how was it that only we could?”

“Don’t you understand, poor boy?” (It was Paul whom Dr. McGillivray addressed, and his voice was grave and quiet.) “There were no messages from us!”

“No messages, sir? But we heard them! There by the airstrip—”

“Of course! We established contact—you know that. We built our transmitter, using the mineral seam as an aerial—you know all that—and MacFarlane, night after night, sent out to you the story of our journey here. Yes, yes indeed! But as the Canal came closer, as it closed around us before we fully knew what its dangers were, so did the Brain within it begin to control our brains. The process is gradual—you know that from your own experiences. We fought to retain our own intelligences; but in the end the Brain defeated us. First it made it impossible for us to send you any warnings. Then it dictated, it dictated the message you have mentioned! Even as, with one part of our intelligences, we recognized and were horrified by what we were doing, with another part, subservient to the Brain, we were asking you to come!—to almost certain destruction!”

“The Vivore wanted us to come? But why—why, why?”

“Because you are young, dear Jacqueline! You are youth and you are humanity! The Canal surrounded us—and the Brain within it probed our brains. We could keep nothing back; and so it came to understand what we were, we alien creatures from across the skies. And what we were, my dear, was what it, once, long ago, had been! But we had succeeded where the Vivores had failed: we had bodies as well as brains—we had managed to preserve both in our own fight for survival on distant Earth. They wrung from us all the secrets of human history—we felt the very thoughts flow out from us and were helpless to prevent it. And so that Brain—that single gigantic Brain—perceived a way in which not only it itself but all its fellows, scattered across the southern Martian wastes, might be renewed. If they could study humanity—could study at closest quarters every aspect of us—perhaps someday they would find out the whole secret of human life and would be able to reconstruct bodies for themselves equivalent to ours. The study would take a long, long time—and the study would have to embrace all aspects of human development indeed. We were two men of middle age, who would die before the secret had been discovered and a way evolved to manufacture bodies like ours to house those huge decaying Brains. They needed younger flesh to study—they had to bring to Mars some children of our kind, so that they could watch them grow! Through us—through our unwilling agency—they sent for you! They forced us to use the one argument that would bring you: that only you, in some way we could not specify, could actually save us!”

“Guinea pigs!” cried Paul. “No more than experimental guinea pigs!”

“We tried to send a warning once—in those very words,” said MacFarlane. “After the message had been sent which they believed might bring you, they kept us confined in the Albatross by sheer force of will power. They had with them a group of the Terrible Ones, picked up somewhere in the course of their journey across the desert, to act as agents, as it were—to do things for them, for as you will understand, without bodies themselves they cannot act in any way. This group of slaves, under their control, tore up with their tendrils the wire connection from our transmitter to the mineral seam aerial. It was the intention, I believe, to keep us alive until there was some sign that you were on your way; if you had not acted on our first message for help, I believe they would have forced us to send more and more, until at last you did come . . . However, one night, with Malu’s help, and exercising all our control to combat the influence from the single Brain immediately before us, we managed to reconnect the wire for a few brief moments. I tried to send the message: ‘The children are to be used as guinea pigs . . .’ and was going on to explain something of the situation. But the Brain found out and made me stop—and the Terrible Ones were sent again to disconnect the aerial. . . . And so you arrived at last, you see; and so we greeted you.”

“They forced us to greet you,” McGillivray picked up, “in the way you know. All the time we were desperate to tell you the truth, but in such close proximity to the Brain we could not. We watched you come closer and closer to certain captivity—and could do nothing! It was nightmare.”

“Doctor Mac was better than I ever was, once he had completely recovered from his illness,” said MacFarlane rapidly. “He was able to gain control for long enough to get you to come into the Albatross, in the hope that we might have Malu’s help there. The Brain did not want that and tried to make me prevent it. I fought as much as I could against the influence, but it was too strong for me. In the end it conceded Mac’s point about your getting into the rocket—the thought once planted in your minds would have been difficult to contradict without rousing too much suspicion before the Brain was sure you were within its net. So it made me hinder two of the party at least, so that it could be sure of some young victims if something went wrong with its major plan.”

“The chocolate!” gasped Jacky. “That was why you asked for the chocolate—!”

“It was all I could think of to make some of you go back toward the tractor. Discophora made me think of some excuse, and in my weakness that absurd one was the only one! And then, of course, as you know—”

We did know—we knew it all now; and those questions not answered in so many words were answered automatically as we reflected on the whole vast horror of the situation. We saw how it was that once they had been carried beyond the immediate power of the Brain, our two friends had regained their own proper control and had been able to tell us all they had told—how it was, even, that while he had been under the influence of the Brain, through all the long months, Dr. McGillivray, in the lucid moments the Vivores permitted the captives on occasions, had been able to formulate his gigantic theory concerning the true secret of the Canals of Mars.

We saw it all; and we saw also why we had been, for a space, permitted to rest in peace on the plain. For the moment the Brain did not need us—because it had, already in its power, three humans of a different nature from McGillivray and MacFarlane: two children and a woman.

Impelled by the monstrous thought, Dr. Kalkenbrenner rose determinedly to his feet. He knew the truth at last: now, somehow, he had to contrive a plan of action—some way to combat the hideous paralyzing intelligence lurking within the tumbling forest a mile away.

His face was set as he turned toward me. He opened his lips to speak. But no words ever reached me. In that one instant two things happened—and so the climax burst upon us.

Something, something unutterably compelling, made us turn our heads toward the distant Ridge—all of us. There, in the clear Martian air, even at the distance of a mile and more, we saw three diminutive asbestos-clad shapes emerge precipitously from the dark green forest wall—rush forward toward us. Katey was a little ahead of the other two—we recognized her taller figure. At a brief distance behind them, moving also at speed, were some half dozen of the Terrible Ones, their tendrils flailing the sandy soil.

All this we saw in one fleeting moment—saw too that although they must have known it would accomplish little, our companions fired frantically over their shoulders even as they ran—sent shot after shot from their revolvers into the yielding fleshy egg shapes of their pursuers.

Then all was lost in a violent swirling of the Yellow Cloud, out bursting from the Ridge to envelop the fleeing figures, swirling beyond them toward ourselves as we stayed motionless regarding the whole wild scene.

And simultaneously, even while we switched on the oxygen breathing apparatus at Kalkenbrenner’s brusque command—simultaneously our ears were filled with a high menacing frequency hum, throbbing through and through us. For one brief second I hovered yet again upon an edge of nightmare bewilderment: then recognized a further danger threatening—for the frequency hum was the alarm signal transmitted to us from the barrier around the distant Comet. It too, remote and undefended, was being attacked—but by what?