Inside the trailer, nothing happened. Lane went grimly through it, making sure there was no opening to the outer air. The ventilator above the small cook-stove was open. He closed it. The result of these precautions was stifling heat, but Lane felt cold chills down his spine simply by thinking of invisible stranglers trying to worm their way in to where the three humans were. There were times, too, when a deep and bitter rage took possession of him.
“Be still!” said Professor Warren irritably, as she paced up and down the confined space of the trailer’s living section. “You make me hot to look at you! I have to think things out. Either we are all quite insane, or the people who used to own the Monster were much more sensible than we’ve been!”
Carol sat quietly, looking from one to the other—her buxom aunt in khaki riding breeches, and Lane seething in citified tweeds. Outside the trailer there was a rocky shelf which loomed over a valley to the east.
“They said that things sat on their chests and stopped their breaths,” Professor Warren went on, “so they ducked under the covers and the ha’nts went away. I was scornful! But now I think that they may have been right!”
Lane forced himself to sit down. He lighted a cigarette. “There was something that tried to strangle me,” he said savagely, “and it whined while it did so. I heard the same sound just outside, and the dog saw something. But whatever attacked me and the Monster was invisible! And that’s impossible! Real things can’t be invisible!”
“Not quite invisible,” the professor said calmly. “What do you think I was trying to do with screen wire set up on the two sides of a bit of buzzard bait? I was trying to see what kept it from reeking to high heaven! Didn’t you ever hold a match six inches from your nose, and look at the world through the hot gases above the flame? Things wobble and waver when you do. How do you think I made up my mind there were gaseous dynamic systems around here? When you look through one of them, things waver and wobble! The things you’re talking about are just as invisible as the column of hot air above a match, which means they’re not easy to see—you have to know what to look for—but they can be seen!” “Then what tried to kill me?”
“Certainly a dynamic system,” the professor insisted. “It had to be. A dynamic system is a parcel of matter using energy in a patterned way. A whirlwind’s a dynamic system. So’s a gasoline engine. Or a rabbit, or a man. Whatever attacked you and the Monster had to be a dynamic system because it used energy in a patterned fashion. Look here! Blow a smoke ring.”
Lane blinked. The professor gestured impatiently. He blew a smoke ring. It went slowly across the stifling hot interior of the trailer, expanding as it went.
“That,” said the professor, “is a very simple dynamic system. It’s a quantity of air which happens to have a toroidal motion. It isn’t alive. It’s only a vortex ring. You can see it because the air of which it’s composed happens to contain smoke. But a vortex ring can exist in plain air just as—”
“Aunt Ann! Look at the smoke ring!” It was Carol, her voice strained.
The professor blinked. Then she looked at the thin, drifting ring of smoke. It was deformed. It was bent on one side exactly as if it had struck something solid.
The professor said, “That’s it! There’s one now! You can see the ceiling waver through it.”
There was a sudden motion of the air. The unseeable something which had deflected the smoke ring moved. The tendrils of smoke wavered and curled through the space from which they had previously been barred.
“It’s one of them!” exulted the professor. “Right in here! But why doesn’t the Monster react? Fetch him out.”
Lane dragged the dog, cowering, from underneath a stool. He held the dog up. The brute panted and wriggled. He gave no sign of fright. His tongue lolled.
“If there is something here,” said Lane, “he doesn’t smell it. And it can’t be seen or he’d see it. It—”
There were now flat layers of tobacco smoke in the air, made visible by sunlight striking into the room through closed glass windows. There was no air movement except the extremely slow general turnover of air in a closed room, but something passed swiftly through those tranquil layers of vapor, disturbing them. It was startling. It was appalling. Lane did not see any wavering of the background behind it.
“Item!” said the professor with satisfaction. “We have a good observation indicating that there are sometimes dynamic systems in air which can move through smoke layers and disturb them. Perhaps we should provide ourselves with sheets to pull over our heads.”
She beamed at Lane, who looked warily at Carol.
“It got in, probably when the dog did,” he said grimly.
The professor rubbed her hands. “Of course!” she said zestfully. “But we know how to keep it from harming any of us! I’m going to catch this specimen and find out a few things about it!”
Lane’s eyes went back to Carol. She was watching all the interior of the trailer with steady, intent eyes—beautiful eyes, Lane thought, but troubled now.
“If it’s what we think, it’s dangerous,” Lane pointed out. “The first thing should be to get her away from this place. I feel responsible. I let the thing in here.”
“Pooh!” said the professor.
She went to a cupboard built into the wall of the trailer, and took out some folded sheets. She shook one open, lengthwise, and tossed it to her niece. It spread out in the air.
The Monster snarled. He cried out at the sheet, barking and snarling and yelping all at once, his voice rising in pitch. The professor’s mouth dropped open. The sheet fell almost upon Carol, but it didn’t reach the floor everywhere. One edge was caught up upon a stool. Besides, there was a spot where something writhed and squirmed and whined shrilly beneath it. That something was roughly rounded and somewhat more than a foot in diameter. It was caught under the cloth, and apparently could not lift it.
The Monster went mad with terror. He made a tumult of fear and ferocity together. He screamed at the somehow horrible shapelessness beneath the white cloth. Yet he cringed away from it as he made his high-pitched din.
But one edge of the sheet was caught on a stool. The throbbing thing seemed to fight its way toward that upraised edge. Suddenly the sheet sagged. Whatever had been trapped was trapped no longer. It seemed to Lane that its whining became a sound of maniacal fury. The Monster dived out of sight and moaned in terror.
Carol made a convulsive movement. Lane jerked his eyes to her. Her eyes were wide and terrified. Her mouth was open. She tried to gasp. She choked, suffocating, beating the air before her with her hands.
Lane plunged toward her, snatching up the cloth, which ripped because one of his feet was on it. He did not notice the resistance. He flung it over Carol’s head in instinctive use of the professor’s dictum that a sheet over one’s head would be sound sense at such a moment.
Then horror filled him. The sheet did not fall naturally about her. It draped over her head, but it enclosed something else. Something huge and invisible clung to her, whining and throbbing.
It was so completely revolting that at any other time Lane would have felt sick. But now he thrust out his hands. Something pulsating stirred his fingers through the cloth. He found Carol’s face while she struggled and put his hands together, scooping away the thing that clung to her. It filled a great part of the remains of the sheet. He clenched it tightly until he’d made the cloth into a bag whose neck he held fast. It was like a rubber balloon imprisoned in the sack, but no balloon ever fought against a cloth that held it, nor emitted a shrill bloodcurdling sound.
Lane’s hair felt as if it were standing straight on end, and horror flowed up his wrists from his hands and fingers. But he twisted the cloth, and twisted it again, compressing the captured tiling into a smaller and smaller space.
And suddenly there was nothing imprisoned in the cloth. It collapsed, and there was a reek of carrion in the air.
Professor Warren was pounding on his shoulders.
“Stop it! Stop it!” she cried furiously. Then she swore briefly. “Too late! You’ve killed it!”
Lane said thickly, “I’ll burn it—”
“Oh, Carol’s all right,” said the professor. “And it’s dead. But we learned some interesting items.”
“I’m going to make sure it’s dead!”
Professor Warren shrugged her shoulders. The Monster moaned and whimpered in his hiding place.
“Hush!” said Professor Warren angrily. She listened, with her head cocked on one side. There was a sound outside the trailer, now. It was a thin, high-pitched whine, save that it was made of many voices and was loud. It gave the impression of a frenzied anger shared by many things.
“Hm,” said the professor after a moment. “After all, it was a brilliant idea to insist that we close all the windows. It sounds as if our guest had friends, and they’ve come to help him or her or it to murder Carol.”
“How can I make sure this thing is dead?” demanded Lane. He still held the limp sack of cloth in his grip. But he was looking at Carol, who had buried her face in her hands.
“If,” said Professor Warren, with a fine air of competence, “if you took a jellyfish and put it in a cloth bag and twisted until you’d wrung the jellyfish out through the cloth, I don’t think you’d be worried about whether it was dead or not. That’s what you did with this thing.” She added exuberantly: “It was alive. It had a certain degree of intelligence. Perhaps a considerable degree. It’s amazing! And if you sniff you can’t help knowing something about its metabolism! No wonder the buzzards were temperamental! There were no smells for them to see!”
She stood still a moment, gloating over her discoveries. Then she moved to the other end of the living space and struck a match. She put water on the small, bottled-gas stove.
“For coffee,” she said beaming. “To celebrate. I’m going to make some notes while the water boils. Wildly imaginative, am I? I’ll show them some wild imagination! A dynamic system of gases, unquestionably living because it has undetermined but demonstrable intelligence, emotional reactions, and at least some degree of communication with its fellows! We irritated it and it called the others while it attacked! Let ’em try to classify a Gizmo like that!”
She sat down and pulled out a notebook. She began to write, absorbedly and swiftly. The Monster moaned. There remained a raging, whining noise in the air outside. Lane listened. He’d been trying for a long time to find an unknown killer of game and men. He’d found a something which not only tried to kill him, but the girl. It had been filled with fury toward a human being. Now others of its kind shrilled the same insane anger.
“Don’t worry!” said the professor, without looking up from where she scribbled. “The thing inside here couldn’t lift a sheet. They can’t turn over the trailer.”
Lane glared out a window. He saw the strained shapes of trees as they grew on the rocky ground. He saw blue sky, very bright as compared to the shadowed mountainside. He moved to the other side of the trailer and looked away, down into the valley. He saw the blurred edge of the mountain’s shadow cast on some of the isolated small fields below. Far out he saw a buzzard in leisurely and effortless flight. The tree branches were still, their leaves motionless. It was a moment of late hot afternoon in which the air should have been filled with the triumphant stridulations of insects and the cries of birds. But there was no sound except the venomous shrill whining of things no man had yet seen, yet which were murderers.
Carol stirred, and he turned to her. She was white and shaken.
“You’re all right?” asked Lane awkwardly. She nodded. But her hands trembled. “Drink of water?” She shook her head.
He sat down beside her. “We’ve got to find a better way of killing them,” he said grimly, “and then we’ll take you somewhere where you’ll be safe.”
She tried to smile. He felt a certain lifting of the spirit. She was exactly what a girl should be. He found himself marveling at the fact that her cheek curved so exactly as it ought, and her lips were exactly as they should be, and that the line of her throat was absolutely the only perfect way that a throat should curve. He had the sensation of discovery which is pure satisfaction. He was delighted to look; he did not wonder where this delight might lead. She, being a woman, probably did. “We’ll have to try fire,” he said sagely. “And there’ll be odors they can’t take. And there’ll be weapons we can make, especially to destroy the organization of the gas they’re made of. We’ll beat them.”
“Of—of course,” she agreed. She hesitated a moment. “Fire might do. I know what Aunt Ann thought about them. She’s said that they’re probably ghosts—or the origin of ghost stories. She says they’re almost certain kin to will-o’-the-wisps and corpselights and such things that float over swamps, shining faintly in the dark. They exist, but nobody’s ever caught one. They must use energy to keep themselves in existence. Aunt Ann has been guessing that the things she’s discovered may use the gases of decay as will-o’-the-wisps use marsh-gas, to supply the energy that maintains them. As we use food. If she’s right, fire might bother them.”
Lane listened with a sort of urgent respectfulness. But he also listened to the whining noise outside.
“Savages,” added Carol, “cover their faces when they sleep. And it’s rare they’ll sleep without a fire going, Aunt Ann says. They believe that ghosts and devils are afraid of fire, and they cover their faces lest evil spirits bother them. If the—things like those that tried to kill us are the things that savages really fear, their superstitions protect them by what they make them do. And the things, if they learned that humans were always protected, would tend to ignore men and attack only lower animals.”
“Except,” growled Lane, “that now they’ve found we aren’t savages and so aren’t protected. But there’s more than that. They must be much more numerous than they’ve ever been before. Or a new and deadly kind may have appeared…” He listened to the whining outside. “These things could have started the tales of fiends and devils; the old stories told of devils tearing people to bits. These don’t even wound animals, but their victims have been found in the middle of destruction. The effect is of violent murder, but the cause could be the violent death struggles of the victims.”
Professor Warren slapped her notebook shut. “Hah!” she said triumphantly. “I’ll pin their ears back! Imaginative, am I? Wait till I march into the Biological Department with some of these things trapped in jars. A gaseous organism with a gas metabolism! … I’ve got to get bigger jars!”
“I’m trying,” said Lane, “to figure out a way to kill them. They’re waiting outside by the dozens now. Maybe hundreds.” It did not occur to him—not yet—that there might be thousands. Or more.
“We can protect ourselves,” said Professor Warren zestfully, “with sheets over our heads. If they can’t stop our breathing, they can’t do any damage.”
Lane was unconvinced. Angry as he was, he could not but remember that there had been a thing—a gas entity—a Gizmo in the trailer. It had made no whining sound. It acted as if guided by cunning, calling no attention to itself until discovered by accident. Perhaps it had meant to wait until the occupants of the trailer were asleep. An attack in darkness and during slumber could be irresistible. In short, the Gizmos might be cleverer than Professor Warren credited. The attempt to kill him had been shrewd, after he escaped the first assault by tumbling into deep dried leaves.
“If you want to try sheets as a protection,” he said shortly, “I’ll try it. I’m responsible for their being here.”
Professor Warren snorted. “Nonsense! Before you got here the buzzards stopped coming to bait because the Gizmos were consuming the gases they looked for. They were here then. And what happened to the gnats and flies and mosquitoes? And the rabbits and the hen quail on their nests? Don’t be absurd! They were here before you came. They didn’t attack us; the one you killed attacked only after it was trapped. But they were around before you got here.”
Lane said grimly: “That’s part of my point. If these things are the foundation for legends of devils, they have the necessities of devils, the first of which is that nobody shall believe he exists. Now that these things know that we know of their existence, they need to kill all of us.”
Professor Warren raised her eyebrows. “I know they’re impossible,” she protested, “even if they’re true. But are you suggesting they’re intelligent?”
“I’m afraid so,” said Lane. “If they were the devils of old legend, they contrived deals by which they were worshiped and supplied with the smells of burned flesh and spilled, rotting blood. The pagan deities—”
Professor Warren grimaced. “Don’t tell me I’ve discovered a pantheon! If they’re intelligent, where’s the evidence?”
“I’ve got an idea how to get it,” said Lane, “if they haven’t the information to keep them from revealing themselves.”
He gathered up the sheet which had been the means of capture and execution of one of the creatures the professor called Gizmos, among other things. He spread the sheet over one of the closed trailer windows. Carol saw what he was about, and came to help. They draped the window so that it was completely covered by the closely woven cloth. Lane knotted it at the corners so that it was tight, yet there was a fullness in the center of the window opening. He made use of that fullness to slide aside the window and open it slightly.
Nothing happened. The distinctly audible whining sound died as soon as he began to fumble at the window. There was no sound at all—no birdcall or chirrup of insects. There was not even the whisper of wind among the trees of the mountainside. In bright sunshine, the unnatural stillness was horrible.
They waited, staring at the curiously draped window. Nothing happened at all. Lane shrugged.
“I thought I’d provoke a mass attack by opening the window. If they were stupid, I thought one might try to poke inside. But if they were intelligent, I thought they’d try to storm the trailer in a rush we couldn’t possibly handle. I was wrong.”
Then the Monster yelped in terror. His hackles rising, he backed into the farthest corner of the trailer, snarling at the open window.
“You were right,” said the professor.
Things hit the draped cloth, which billowed out tautly. It almost seemed to stretch with the violence of massed Gizmos pushing against it. They tore and tugged at it, their whining filling the interior of the vehicle. It was unspeakably horrible that they should rave so terribly at so flimsy a barrier, and not be able to rend it.
Lane leaped toward the window. The sheet could not be torn. But the tuggings and throbbings of the individually weak murderers were loosening the cloth from the corners of the window frame. One edge billowed momentarily, and a vicious whine of triumph flashed past Lane. He heard Carol cry out.
He thrust back the barrier. He beat at the cloth with his fists, as if to destroy the yielding things by blows. Carol cried out again: “Aunt Ann! Here! Come here!”
There were strugglings. The Monster screamed and snapped. It fought madly against unseeable nothingness. Another part of the cloth barrier bulged to its very edge.