STAR TIGER
Lieutenant General John Wilforce knew the saying that trouble comes when least expected. It occurred to him as he finished his shower and toweled briskly. He was still considering it as he slid between the cool sheets for his first full night's sleep in six months.
Wilforce lay still, hearing the rumble of the automatic loaders that poured fuel, food, and ammunition into the flagship's tanks and storerooms. In his mind's eye, he could see the ships of his fleet. Most of them, like his own, were drawn close to the starlit framework of girders, drums, crates, and pressurized spheres that was Space Center 12. From these ships, thousands of his men were now streaming into the bars, game rooms, and psychosynth parlors of the Center, eager for a few hours of release and forgetfulness after the brutal months on Inferno.
Before letting himself fall asleep, Wilforce reviewed his precautions. He had detached a strong squadron of the fleet to reinforce the guard ships of the Center. Half the men in each ship now reloading at the Center were on board, ready for duty at a few minutes notice. Moreover, the latest reports showed no sign of trouble whatever, anywhere in his sector.
Satisfied that he had done his job, the general pulled the covers close around him, and fell sound asleep. Unnoticed as he slept, the hands of the clock on the communicator by his cot swung slowly around their dial until, in the early hours of the morning, a red light blinked on.
Wilforce woke with a hammering clang in his ears. He threw back the covers to see the communicator's red warning light flash on and off. Then the screen flared into life:
CLASS A EMERGENCY!
CLASS A EMERGENCY!
CLASS A EMERGENCY!
Wilforce swung to the edge of the cot and hit the "Receive" stud. On the screen appeared a man with three stars at his collar and his shirt plastered to his skin with perspiration. Clouds of vapor rolled past behind him as he said: "General Wilforce?"
"Right here." Wilforce snapped on the room light so he could be seen. He recognized the man now as Larssen, armed forces commander in a sector bordering his own.
Larssen, a note of strain in his voice, said, "General, are you still tied up on Inferno?"
"We just got back from it."
Larssen hesitated barely an instant. Then he said, "A little over the border from you in my sector is a sun system called Bemus. There are colonies on the third planet, and they've been there better than ten years with no trouble. I also have a small rest camp on the planet. At last report, a month ago, everything was fine."
Larssen paused, then said, "Three days ago, a destroyer of mine crash-landed on Bemus III. Every colony there has been smashed. All records, books, food, and clothing are gone. Weapons are strewn all over. There's not a human being left. There are abundant tracks of animals entirely different from those native to the planet, but the animals themselves aren't to be seen."
Wilforce listened intently.
Larssen went on. "The detector network shows nothing approaching or leaving the planet. The result is, I don't know what happened on Bemus III. Right now nearly everything I've got is tied up. Yet, if something can get past the detector network and wipe out a whole planet, I can't ignore it. Can you help me?"
Wilforce said, "I'll do everything I can."
Larssen thanked him fervently, and promised to have his staff send immediately every scrap of information available about Bemus III. The screen blanked, and Wilforce punched a number on a vertical row of buttons to the left of the screen. The competent, slightly pudgy face of Rybalko, his chief-of-staff, appeared.
Wilforce said, "Did you hear that, Balky?"
"Yes, sir," said Rybalko. "I heard it."
"How long will it take us to load up?"
"Sir, to do it right will take another five days."
Wilforce thought a moment. If he waited, the trouble, whatever it was, might have time to develop. If he immediately took his full fleet to Bemus, he might by sheer force crush the thing at its beginning. On the other hand, experience told him that he might find himself making gestures in empty space, and be forced back in a few weeks for lack of supplies. He made up his mind, and glanced at Rybalko.
"Balky, get a light task-force together to prowl around Bemus system. Load a D-transport with Pioneers to scour Bemus III and piece together what's happened. Put a combat group on another D-transport to back up the Pioneers. Then get in touch with the destroyer that crash-landed on the planet. I'll want to talk to the commanding officer."
"Yes, sir."
Wilforce got up, splashed cold water on his face, and got dressed.
The destroyer's commanding officer turned out to be a spare major with craggy features.
Wilforce said, "Major, exactly where are you on the planet?"
The major held up a map. "Sir, we're in the planet's northern hemisphere here, about three hundred miles southwest of the rest camp. The terrain where we came down is a gently-rolling, dry, grassy plain. We're at the point marked 'X' here on the map, about twenty-seven miles north of the big loop of this river."
"What's your situation right now?"
"Well, sir, we have plenty of supplies. An abundance of fresh meat. And we haven't been threatened in any way. We've scoured the five-hundred mile radius of territory we can cover thoroughly with our light fliers, and we've let out Bats and Probes to scout farther out. We can't find anything that looks dangerous—except that the colonies and rest camp have been totally wiped out."
"Have you taken pictures?"
"Yes, sir. As soon as we realized what had happened, we started taking them. We're getting ready to send you a batch on the trifac right now."
"Good work. Now, how did you happen to crash-land on the planet in the first place?"
The major hesitated. "Sir, to be perfectly honest, I don't know what happened. None of us knows. We were making a routine sweep through this part of the sector, and swung close to the planet because we couldn't get any response from the communications center down at the rest camp. Then something hit the ship like a hundred tons of lead. The next thing we knew, the air was whistling out. Seams parted here and there the whole length of the ship, and we barely had time to get into suits. There was nothing on the detectors that could have caused it, but there we were just the same. I decided to set down on the planet to replenish the air and repair the ship. But we'd had even more damage than I realized. On the way down, several drive tubes blew their linings, and a gravitor broke loose from its mount. That was how we came to crash-land on the planet."
"Do you have records of your detector readings?"
"Yes, sir. We can run the record tapes through the trifac if you'd like."
Wilforce said, "Yes, do that, from the time you entered Bemus System till you landed on the planet."
"Yes, sir."
"How are your repairs coming?"
"We expect to have the seams sealed up, the gravitor mounted, and the tubes lined in about two weeks, sir. Straightening the frame will be a job for the yards at Main Base. But we should be able to get back all right."
Wilforce thought a moment. "Major, take several three-dimensional photos of the damage to your ship and send them along, too."
"Yes, sir."
"Is there anything else that seems important to you?"
"No, sir. Nothing I can think of."
"All right. Have your communications officer signal us every hour, and get in touch with us right away if anything further happens."
"Yes, sir."
Wilforce broke the connection. Shortly afterward, the first reports and photos of the colonies came in on the trifac.
Wilforce first located some maps in the growing pile sent in by Larssen's staff. The maps showed the colonies on a gently rolling, heavily forested plain. They were located in a circle several hundred miles across, with Larssen's rest camp in a cleared rectangle near the center.
Looking over plans and photographs, Wilforce saw that the individual settlements were large clearings near lakes or streams with L-shaped rows of cabins along the south and west edges of the clearings. But these rows of cabins were laid out differently from those Wilforce had seen on other heavily-forested planets. Instead of being simply straight rows of cabins, each cabin was turned roughly thirty degrees from a line due south or west. From above, each row of cabins suggested a row of dominoes lined up end-to-end, separated to leave spaces between them, then each pivoted thirty degrees about its center.
Wilforce puzzled over this till an explanation dawned on him. In a straight row of cabins, gunfire from one cabin couldn't reach the space close to the front or rear walls of adjoining cabins. By turning each cabin, its front and rear walls could be protected by neighboring cabins.
The next thought to occur to Wilforce was, "What enemy?"
Methodically, he worked his way through reams of information on the planet, and wound up some time later with a faint pain between the eyes, and a summary of all the data that seemed to count:
"Bemus III is an Earth-type planet, with ideal gravity and atmosphere, a reasonably pleasant climate, and a somewhat longer than standard year. It has few mineral resources, but rich soil and abundant forests. There are no plants or animals harmful to man. The largest life form is a placid, herbivorous, mammoth-like creature called a 'cropper' which is protected by Planet Certification because it is nearly extinct. The other herbivores are small. The largest carnivore is a shy nocturnal creature little larger than a rabbit. Man has no enemies on Bemus III."
With this fresh in his mind, Wilforce reached for photographs and diagrams of Larssen's rest camp. A glance showed him that the camp was made up mostly of tents and prefabricated one-story barracks put up and taken down as needed. Then Wilforce looked at the only permanent buildings in the camp—the communications center.
Built in a tight hollow square, from the middle of which rose a covered tower mounting a machine gun and a big searchlight, the communications center was surrounded by a stockade of upright logs, sharpened on the ends. A barrier of packed earth filled the space between this stockade and an outer log wall that looked from above like a four-pointed star. Emplaced within the barbed-wire-strung arms of this star were heavy machine guns and multiple rocket launchers. Outside was a broad deep ditch ringed with more barbed wire.
Wilforce looked at this a moment, then glanced back to the reports that described Bemus III as a peaceful harmless planet. He carefully checked to see if by any chance he was reading data on two different planets with similar names. When he was satisfied that this wasn't the trouble, he glanced with a deepening scowl at the pile of recent photos sent in by the destroyer.
These photos showed solidly-built cabins knocked askew, doors smashed in, guns still at windows and loopholes, axes and unsheathed knives strewn on the floors. At the communications center, the massive logs at one part of the outer wall were snapped back like toothpicks. The earth behind was pulled down as if by a giant hand, with a machine gun lying in the dirt at the bottom. Two of the communications buildings were knocked apart. The tower had long splintered scratches, several braces torn loose, and its roof ripped open.
Wilforce looked at one photo after another, then at the views of the destroyer with its side flattened in the aft section and slightly dished-in forward.
Frowning, he had several photos of the rest camp and the ship enlarged. 
The ship appeared to have been hit by a solidly-built cylindrical object about its own size, and nearly parallel to it at the time of collision. The enlarged photos of the ruined colonies showed deep parallel scratches in cabin walls, big paw marks in the dirt outside, and in one place behind a low swell of the earth, the outline of an enormous body with fan-shaped marks in the earth behind it. This suggested to Wilforce a huge cat crouched in wait and thrashing its tail.
Scowling, Wilforce put down the photos, and went out to make a quick check of the condition and equipment of the troops being sent to Bemus III. He found that the equipment had been brought almost back to normal. But the combat group was depleted in both men and officers, and somehow looked none too good to him. Finding nothing specific that was wrong, he attributed it all to the recent ordeal on Inferno, wished the men luck, and went back to the problem of Bemus III.
Five days later, the one significant change in the situation was that the reloading of Wilforce's ships was complete. His main fleet now blasted off for Bemus III. En route, Wilforce wrestled with the conflicting data, but it still proved impossible to fit it into any sensible pattern.
The trip to Bemus III was expected to take about sixteen days. Before they had been gone one full day, the destroyer on the planet stopped transmitting reports, and could no longer be reached.
When the fleet was still better than five days out from the planet, the commander of the fast task force sent ahead of the fleet reported back to Wilforce by communicator.
"Sir," said the officer, frowning, "we've just completed our first sweep through Bemus System. If there's anything out of the ordinary here, we haven't seen it. The one thing I don't like is this big belt of asteroids between the third and fourth planets."
Wilforce nodded. An asteroid belt could confuse the detectors and incidentally conceal whole squadrons of hostile ships. Wilforce said, "When do you intend to land the Pioneers?"
"In about four hours, sir. They're coming through right now. We expect to keep the troops close by, but offplanet unless the Pioneers run into trouble."
"Good," said Wilforce. "Have the Pioneers report to me as soon as they find out what happened to that destroyer."
"Yes, sir."
Wilforce spread out several big charts of Bemus System. Later that day, he was rechecking his plans for approaching it, when Rybalko came over, his face pale.
"Sir, the Pioneers have found the destroyer and boarded it. We have them on the screen."
Wilforce put down the chart and went over to the screen, where a man wearing the customary fringed leather shirt of the Pioneers knelt beside a long low shape covered with a rough gray blanket. As Wilforce came over, the Pioneer pulled back the blanket.
Underneath, stretched full length on the metal deck, lay a bare human skeleton.
Wilforce drew his breath in slowly. He noted the thin steel chain that looped loosely around the vertebrae of the neck to hold the dull metal tags. He saw, flat on the floor nearby, a shiny cleaver, the plastic inserts in its handle missing.
The Pioneer glanced at Wilforce. Wilforce nodded, and the Pioneer pulled the blanket back over the skeleton. He said, "We've found eight more of these in just one section of the ship. That's all we've found of them. Outside, there's only tracks. Mr. Pick said he wants to have a better idea what happened before he gets in touch with you. But he'll call you in three hours at the latest. Is that all right?"
Wilforce thought a moment. Pick was head of the Pioneers attached to Wilforce's command, and he generally worked best when given plenty of freedom. Wilforce said, "Does Pick need reinforcements?"
"Not right now. He doesn't want them."
"All right."
The screen blanked, and Wilforce glanced at Rybalko. "After we break out of subspace, I want one squadron located to smash anything that raises its nose in the densest part of that asteroid belt. I also want selected sections of the belt saturated with reconnaissance torpedoes. You might have the data run through the computer now, and we can see what the best pattern seems to be."
Rybalko said, "Yes, sir. Sir, did you notice that cleaver?"
"I noticed the handle. But we won't really know much till we talk to Pick."
Jeremy Pick was on the screen a little over three hours later. He was a tall man with a high-bridged nose and light gray eyes that shifted warily as he talked. He said, "General, I don't know exactly how to describe this place. It's too quiet. And for some reason we feel even more uneasy inside the ship than out."
Wilforce said, "You didn't find any survivors in that destroyer?"
"Not a one. We've found nine skeletons, and that's all. Outside, there's scattered weapons and equipment. Apparently, the men were overrun in a rush before they had a chance to act."
"Overrun by what?"
"To judge by the tracks, by carnivores measuring around twelve feet between the fore and hind limbs, and weighing up to thirty-five hundred pounds."
"Have you seen any of these animals?"
"No. We've seen some herbivores that aren't mentioned in the survey reports; but they might be the young of these 'croppers.' We haven't seen a single carnivore of any size yet."
Wilforce scowled. "Is there any place they could hide? Or could the carnivores be nocturnal animals?"
Pick shrugged. "It isn't dark here yet, so I don't know. Maybe they'll emerge from somewhere. But I've had clouds of small reconnaissance probes buzzing all over this section of the planet since we landed. If there's any carnivore that big around, it's either invisible, or else it's hugging the mud on a river bottom."
"Do you have any idea how the destroyer came to be taken by surprise?"
"Well, they had one of the big gravitors partly spread out outside, so I suppose they were spreading the parts out in the sun to dry. We checked and found where a section of coolant line had burst in the gravitor, so that much makes sense. Other crewmen were relining the ship's drive tubes. Some of the maintenance hatches were open in the aft section of the ship, along with the loading hatch, so it must have been easy for anything to get in. As nearly as we can figure out from the remains of the log, they had scoured this section of the planet, found nothing dangerous, and weren't worried."
Wilforce said, "You say, 'remains of the log'?"
"The log is partly eaten up, as if by mice."
"Have you seen any mice?"
"None. And we haven't found any droppings."
Wilforce said exasperatedly, "That's a peculiar planet, Pick."
"It's peculiar, all right. The more we find out, the less sense it makes."
"If those giant carnivores can show up by surprise once, they may do it again. Are the hatches shut now?"
"The hatches are dogged tight. No one goes in or out except through the air lock. I've got half-a-dozen Bats cruising around outside waiting for any carnivore to so much as raise its snout. All the same, I don't exactly feel at home in this place."
Wilforce thought a moment. "Listen, why not move one of the communicators into some part of the ship where we can watch what you're doing, and then leave it on. If anything happens unexpectedly, we'll know about it."
Pick said, "Good idea." They talked a little longer, then went back to work.
While still about a day out from the planet, Wilforce was in the flagship's command center studying the computer's suggested deployment. A call from the task force commander was relayed to him, and the man appeared on the screen with a look of alarm and uncertainty. "Sir, we've got something here, but I don't know what."
"What do you mean?"
"About fifteen minutes ago, our detectors picked up an object roughly the size of a destroyer. We were standing by off Bemus III, and the object passed between us and the planet, moving at about two miles a second. It stayed on the detectors a little under three seconds, and then it vanished. We can't locate it. There was no sign of it before, and there's been no sign of it since. But we've checked, and the detectors of every ship in a position to pick it up did pick it up."
Wilforce looked away a moment, then said, "How far from the planet was this object?"
"About twenty thousand miles, sir. It was moving as if it was in orbit." 
"It sounds as if it's in orbit. Calculate its projected course as well as you can, and have a ship trail it. If it comes in sight again, learn all you can, but for now don't interfere with it. Just watch it."
"Yes, sir."
Wilforce had just finished this call, when Rybalko came over. "Sir, Mr. Pick was just on the screen. I didn't want to interrupt your call, so I took it myself."
"What did Pick want?"
"Reinforcements, sir. He's run into a peculiar situation. He's lost several men. One of them was carried off by a carnivore about the size of a tiger, that was apparently lying in wait in a ruined cabin. A probe was overhead, and had the carnivore in sight as it vanished in a patch of thick brush. The animal had no time to get out of the brush before other probes had it in view. Pick and a crew of Pioneers took the brush patch apart bush-by-bush. No carnivore came out. No carnivore was in there."
"You mean, this tiger went in. It didn't come out. And when they looked, it wasn't there?"
"That's what he says, sir."
Wilforce frowned. "How did Pick seem?"
"Jumpy. He had a fusion gun in his hand and kept glancing around all the time. But he sounded rational enough."
"All right. Send the combat group down to back him up. And have Pick send up reproductions of the visual records from the probes that had this in view."
"Yes, sir."
Rybalko went out. Wilforce turned to look at a large three-dimensional image of Bemus System, his planned deployment outlined on it. The computer had helped perfect the details of this deployment, but Wilforce was now thinking that the most accurately detailed plan is questionable if based on questionable information. With a vanishing ship flitting through space near the planet, and disappearing animals on the planet, how was he to make a satisfactory plan?
Bit-by-bit, allowing for large uncertainties, he began to revise the plans.
Rybalko came in when Wilforce was part way through, and stood watching the symbols on the big three-dimensional image.
Wilforce looked up and Rybalko said, "Sir, the records of the probes watching that carnivore are starting to come in."
"Good. I'll take a look at them later, if I have time. Have Evaluation go over them and see what they think."
"Yes, sir." Rybalko hesitated, looked at the projected plan, then said, "Did you think we should make a more gradual approach, sir?"
Wilforce nodded. "When you're locked up in a dark cellar with some one who may be an enemy, let him make the first big move. Of course, you can always toss out something small and see if he jumps for it when he hears the clatter."
Wilforce's fleet was normally organized in five divisions. The fast ships of one division made up the task force that had gone ahead. Wilforce now took the remaining ships of this division, plus his own center division, out of subspace toward Bemus III. Behind him in subspace lay sixty percent of his striking force, ready to attack at a moment's notice.
In the command center's big, three-dimensional battle screen, Wilforce could now see the first stages of his deployment working out as planned.
The bright lines arcing closer to the sun Bemus showed the paths of fast transports carrying mobile racks of the disks that would be sowed in long rows, each to exude a puff of loose silvery material that could expand at a given signal to a wide thin doughnut with a dazzling film of silver stretching across its center. And that could, at another signal, contract, turn together through specified angles, and again expand, to focus an unendurable blaze of solar energy in a selected region nearby or far away.
Wilforce watched the bright lines that marked the transports slowly separate as they raced to their separate positions. He glanced at the asteroid belt, represented in the battle screen as a stream of green-colored dots. Any abrupt change of speed or direction would cause the dots involved to turn red. So far, they remained green.
Toward the sun from the planet Bemus III, were the four pale blue spheres that represented the four sections of his diminished fleet. These spheres were grouped as at the four corners of a huge tetrahedron. From them, a spray of fine lines reached out toward the planet like the fingers of a giant fist. These were the advance scouts, that would scour the planet from pole to pole, to provide a picture in which Wilforce hoped to find some pattern that would give a clue to past events.
As the transports approached their final positions, and as the scouts let loose their clouds of probes, Wilforce waited, tensely alert.
The ideal time for an enemy to strike slid past.
Nothing happened.
The transports reached their positions, and sowed the racks that sowed the disks. The solar beam was ready.
The scouts sent back a flood of aerial photographs and data, for Evaluation to fit together into a coherent picture of Bemus III.
Still nothing happened.
Wilforce looked at Rybalko.
Rybalko looked blank.
Time passed. And still nothing happened.
Wilforce thought over his dispositions. Sixty percent of his fleet was like a hidden club, which he could bring out at any time. The other forty percent, himself included, acted as bait. The probabilities seemed to show that something wished to remove humanity from Bemus III. Therefore, if he immediately proceeded to take over Bemus III, the something should strike. If it struck, he might very well be able to strike back. If he was unable to strike back, then, at least, the extent of the danger would be uncovered. But now, nothing happened.
In time, Rybalko said, "Sir, first reports from Evaluation show nothing unusual on the planet, except some large herds of herbivores—apparently offspring of the croppers."
"Herbivores. No carnivores?"
"None seen yet, sir."
Wilforce nodded. Methodically he went back over what he knew about Bemus III. All reports showed it to be a placid quiet planet, with no natural enemies of humanity on it anywhere, but all the same, the colonists had built their settlements as if they expected attack any time. And the colonists had lived there unmolested for over ten years—then suddenly had been wiped out.
Wilforce scowled, and then considered the rest camp. Nearly all the buildings in the rest camp were light and temporary. They could no more hold off an attack than a blotter could seal out water. Obviously, no attack was feared. But on the other hand, there were those few permanent buildings in the rest camp. And these were fortified like a frontier outpost on a planet swarming with reptilian monsters. Obviously, an attack was feared.
Wilforce drew a deep breath, and turned his thoughts to the destroyer. Its crew felt sufficiently sure there was no enemy around to leave their ship and work outside. The Pioneers, much more capable of defending themselves on a strange planet, felt so uneasy that they were jumpy inside a locked-up destroyer that could make mincemeat of endless carnivores—granted only that the people inside were on their guard.
As if this were not trouble enough, there was the problem of the way the destroyer had arrived here in the first place. It was on the planet because of a collision with, or a blow from, some invisible object. Just such an invisible object had now momentarily come into view of the task force off Bemus III, only to vanish again. Why appear in the first place? Why vanish?
And now, Pick had lost several men despite precautions, one of them eaten by a carnivore which was plainly seen to go to a given place. When the place was examined, the final result was that the carnivore had gone in, he hadn't come out, and he wasn't there.
Wilforce swore aloud.
Rybalko looked up. "Sir?"
"Nothing," said Wilforce. He forced his attention back to that incident of the carnivore. There, at least, was something definite. Methodically, Wilforce considered the possibilities. To begin with, either the observation was correct, or there was some mistake. On any other planet, Wilforce would have thought it was a mistake. But here, it fit the pattern perfectly.
In that case, assuming Pick was right, what could have happened? Wilforce thought hard, and ended up with only a few possibilities that seemed reasonable. First, either the animal had merely ceased to exist, which was ridiculous, or it had not. If it had not, then it was either still in the place where the brush patch had been, or it was out of it. This led to a few possibilities that should be checked. If in the patch, it would seem that the animal must have a well-concealed burrow. If out of it, it must have gotten out by an underground burrow, or on the surface. If on the surface it must either actually have been invisible, a possibility Wilforce did not enjoy thinking about, or it must have very effective protective coloration.
Wilforce sat down at a communicator, and called Evaluation. A weary-looking captain appeared.
Wilforce said, "Captain, do you have some films from Mr. Pick's probes showing a carnivore that attacked one of the Pioneers, then disappeared in some brush?"
"Yes, sir," said the captain. "We've been over that sequence till we can't see straight."
"Can you summarize it for me?"
"Yes, sir. The Pioneer was examining tracks outside the cabin, which was badly smashed up. Several other Pioneers were nearby with guns keeping an eye on things in general. A large, somewhat tigerlike carnivore came out of the cabin in one blur, knocked the Pioneer flat, seized him in its jaws, and sprang behind another cabin. He was behind the cabin before the men could fire. There was a gravsled nearby, and they jumped into it, but the carnivore had already bounded to a patch of tall, widespread, thickly branched brush. There was a Bat overhead that they could have used to kill the carnivore, but that would have blown the man to bits as well as the carnivore. Well, sir, by this time the carnivore could have been in any of a number of places in that brush. There was thick foliage overhead, but ample room to move around underneath."
"Then what happened?"
"A probe had been overhead to catch all this. It was immediately shifted to cover more of the brush, and other probes were quickly switched in to cover the rest. This all happened very fast."
"Could the animal possibly have gotten out before the coverage was complete?"
The captain shook his head. "Sir, I don't think so. You see, those probes were nearby. All the brush wasn't being observed right then, but there was a complete ring of territory around the brush that was covered. The probes were moved in such a way that this ring of observation was never broken. It was merely contracted till it included the brush. For the carnivore to have gotten out of the brush, it would have had to move very fast, and it would still have had to cross space that was under observation. It didn't."
Wilforce nodded slowly. "What happened next?"
"Mr. Pick and a small army of Pioneers methodically hacked the brush apart piece-by-piece. They worked shifts, using floodlights and flares to keep the place lit all night long. There was no time it was really dark in there. Finally, they had the whole thing taken apart, and there was no carnivore."
"Did they find anything in there?"
"Yes, sir, they drove out quite a number of small animals, a herd of pretty big herbivores, and a flock of birds. You see, the brush patch was made up of tall bushes that grow large edible berries, so the animals were attracted to it. But the carnivore wasn't in there."
Wilforce was silent a moment. "You checked this a number of times?"
"Yes, sir."
"What chance is there the animal could have crawled into some crevice or concealed burrow in that patch of brush?"
"We thought that must have been what happened, sir, but since then the Pioneers have gone over every square foot of ground, and they haven't uncovered a thing."
Wilforce thought this over. Then he nodded. "Thank you, captain."
"You're welcome, sir."
Wilforce next decided to call Pick. A jumpy-looking Pioneer appeared, to say, "General, he's down in the food storeroom right now, and he's mad as a Martian rat in a rainstorm. I'll try to get him if you want, but you can't expect much."
Wilforce laughed. "Go ahead. I'll take my chances."
The Pioneer turned away. There was a mutter of voices. Wilforce even overheard the word "sir" once or twice, and he knew the Pioneers were constitutionally indisposed to use that word. Several minutes passed, and the Pioneer reappeared on the screen, red-faced and mopping his brow. "He'll be right up."
Pick came on the screen tight-lipped and silent, with an expression around the eyes like a panther with its tail in a trap. He glared at Wilforce and said, "Do you have something called a stalker's helmet?"
"Special Equipments probably has some. Why?"
Pick drew a deep breath, and seemed to struggle to calm himself. "We've got some kind of small rat in the food stocks. We don't see it. We don't hear it. It leaves no droppings. But it eats. We want to see it in action, if possible. It also occurs to me we might need something like this 'stalker's helmet' I've heard of. It's supposed to be a new item of Space-Force emergency equipment, isn't it?"
"Yes, but I don't know anything more about it. How many do you want?"
"Three should do it."
"O.K. Now, about that carnivore you spotted, and that ran into the brush—"
Pick shook his head. "It went in. It didn't come out. And it wasn't there afterward. That's all I can say. We've found no sign of a burrow whatever. We've been over those films till we're black in the face. Maybe by some form of clever camouflage the animal could have slipped away without our seeing it at the time. But we'd spot it when we checked over the films afterwards. So that isn't it, either. We've examined those films inch-by-inch, and what happened I don't know, but no visible carnivore came out of that brush, and that is all I can say."
Wilforce said, "Well, that leads us nowhere."
"So," said Pick, "I am going to concentrate on the vermin on board this ship. If I can get a grip anywhere on this mess, maybe I can straighten it out. So far, I feel like a man trying to swim in empty space."
Wilforce nodded sympathetically, then suddenly got an idea. He glanced around and saw Rybalko coming across the room from a group of staff officers. Wilforce said, "Balky, does the 186th still have its mascot?"
"Yes, sir. I'm sure of it."
Wilforce turned back to the screen. "Pick, I think I know where you can get just what you want—a full-time expert on rats, with endless patience, great stalking ability, and extra-sensitive vision."
"Where's that?"
"Get in touch with the C.O. of the 186th Combat Group. If you explain your predicament, and promise to take good care of him, the 186th might let you borrow their mascot."
Pick frowned. "What mascot?"
"A big, ugly, tiger-striped gray tomcat. For your own sake, be careful how you handle him. He's a little rough."
Pick's eyes glinted. "That's the best idea yet. Do you have anything else you want to ask me?"
"No."
"O.K. Get off the screen so I can call the 186th."
Wilforce punched several buttons to the side of the screen. A second lieutenant appeared.
"Sir, Special Equipment."
"Do you have any stalker's helmets around?"
"Stalker's helmets? Just a moment, sir." He turned and called out. An answering call came back. The lieutenant turned around. "Major Barnes will be here in just a minute, sir."
A medium-sized man with major's leaves appeared. Apologetically, he explained that stalker's helmets were new items of equipment that weighed thirty-two pounds apiece, and were just a little clumsy. "They haven't got all the bugs out yet, sir."
The major turned to bark orders at the lieutenant, who vanished and reappeared with a thing like a dull-gray inverted fishbowl with a set of eyepieces sticking out in front, in back, on both sides, and on top. Wilforce was reminded of the high-pressure spheres in which Planet Certification lowered its men to the ocean depths.
"You see, sir," said the major, "the idea is that when a man moves, he's seen. But he has to move to see what's going on around him. So this helmet is rigged up in such a way that by a very slight inclination or rotation of the head, the lines of vision of the man wearing it can be switched through lenses and prisms to any one of these sets of eyepieces. In theory, he can see what's in any chosen direction. In practice, after a man has carried this weight around on his head for any length of time, he finds it hard not to move his head slightly. The result is, he sees alternately right, left, forward, back, and out the top of his head. Trying to walk in one of these is like a madman's nightmare."
The major paused, and added apologetically, "If you still want one of these, sir, we've got them. But I'd wait till the improved model comes out."
"I see your point. Well, write a brief note explaining the shortcomings of these things, and how they're supposed to operate and send three of the helmets down to Mr. Pick."
"Yes, sir."
Wilforce turned away as he finished the call, to glance at the battle screen. Nothing significant appeared to have happened, and as he paused to review the situation and decide what to do next, the red warning light on the communicator beside him flashed on.
Wilforce snapped on the communicator. A neat officer with a look of intense self-discipline, wearing two stars on each shoulder, saluted stiffly. This was General Davis, Wilforce's Combined Forces Commander. In a full-scale planetary war, Davis would control the combat forces actually on the planet. But right now, there was only a single combat group on Bemus III. Puzzled, Wilforce returned the salute.
Davis said, "Sir, I have to report a case of gross dereliction to duty, regarding the commanding officer of the Forty-second Combat Group on Bemus III."
"What's happened?"
"Sir, the purpose of landing the Forty-second on the planet was to enable us to very quickly send help to Mr. Pick, if he needed it. To be able to do this, the major commanding the combat group should hold his forces mobile and ready to act at a moment's notice. This hasn't been done." Wilforce frowned, and Davis went on. "His troops are digging themselves in. Instead of being heavily armed, the charges for their fusion guns are locked up inside one of the communications buildings. The proxex and impax ammunition are locked up in another building, so the men have nothing but ordinary target rounds. The grav-carriers are stacked in the communications compound, along with most of the rocket launchers. Specially-selected, heavily-armed troops that the major feels he can trust man the walls around the communications center, where he has his headquarters."
Wilforce seemed to feel his collar grow tight. " 'Troops the major feels he can trust'?"
"Yes, sir."
"Go on."
"Sir, that's it. The major has his nest in the communications center. Selected guards man the wall to protect him from his own troops. The bulk of these troops are armed after the style of 1912. They dig their foxholes and trenches by hand, and have to hunt for food in the forest nearby."
An unlovely combination of words rose to the surface of Wilforce's mind. With an effort, he kept his voice level as he asked, "It's like this right now?"
"Yes, sir. It will be at least an hour-and-a-half before I have it straightened out."
"I see. How did you find this out?"
"I saw the unfinished trenches on a high-level photo from one of the scout ships. It seemed to me they could have had those finished long ago. I shifted focus on the viewer, and discovered they weren't using a trencher. They were doing it by hand. I snapped on the screen to get the Forty-second's commanding officer, but a medical officer appeared and told me the C.O. was suffering from nervous strain, and I couldn't talk to him."
Wilforce loosened his collar.
Davis said, "It took me very nearly five minutes to break through this asinine situation, and get the major on the screen. The major was dead drunk. The medical officer now intruded to inform me that this was 'therapy.' It appears that the major is suffering from a chronic state of anxiety, which is relieved by the situation down there as it now exists. Unless we handle him with padded tongs, we are likely to upset his emotional balance."
"You say it will take an hour-and-a-half to get him out of there?"
"Yes, sir. I'm sorry. I have near the planet a colonel of Scouts who's had a good deal of experience with troops, but it will take that long to get him on the spot."
"That's too long. All hell may break loose down there any time."
"Sir, in the rat's nest atmosphere of the Forty-second's headquarters, I can't find anyone qualified to command. And we can't risk having it bungled."
"That may be, but it won't do. An hour from now, the Forty-second may have suffered fifty percent casualties from a few monsters that one properly handled fusion gun could chop into hash. Not only is it bad in itself, but it makes a story that will be told for the next fifty years. A thing like that can spread cynicism and rot through the service like a virus spreads disease."
"Yes, sir. But—"
"Wait a minute." Wilforce thought back to his quick inspection of the Forty-second's equipment just before they left the Space Center for Bemus III. He thought he remembered something. He said, "Find out if they have a full-range battle transceiver down there."
"Sir, we used almost all of them on Inferno, and the Center didn't have any new stocks."
"Check and find out."
"Yes, sir."
Wilforce glanced around, to see that nothing of any importance seemed to have happened. He frowned, thinking back to the appearance of the Forty-second at the Center, and wondering why he hadn't noticed anything. There had been something—a general washed-out spiritless look of the troops, and a sort of nervous over-cordiality in the commanding officer—but Wilforce had attributed it to the long misery on Inferno, and the wild binge to celebrate getting off Inferno, followed by the news that they were being sent to some new mess that wasn't even in their own sector. Wilforce glanced back at the screen, where Davis reappeared with a surprised look.
"Sir, they do have a battle transceiver."
"Good. Have them set it up on some rise of ground between the communications center's outer wall and the trenches."
"Yes, sir."
Wilforce turned to Rybalko, and told him what he was going to do. He added, "If we have any trouble back here, I'll want to know immediately. Have a competent officer in a monitor booth ready to take over the transceiver."
"Yes, sir."
Wilforce glanced at the communicator, where Davis returned to say, "Sir, they're setting it up."
Wilforce said, "Good," and walked swiftly to one of several blocks of thick-walled booths that stood at an angle to the rear wall of the command center. He stepped into one, and shut a thick door behind him.
Directly in front of him appeared a sweep of slightly-rolling ground cut by trenches where men dug slowly with picks and spades. About five hundred feet away was the forest. To right and left, the forest stretched farther away. Wilforce turned, to see behind him a faint line outlining the door of the battle transceiver booth, and, beyond that, a high wall of thick upright logs.
A little distance away, holding their fusion rifles at the ready, were two burly privates. A sergeant stooped to check the dials of a brown box near a power cable that ran back across a ditch and over the wall into the communications center. For an instant, Wilforce felt his usual sense of disorientation, and reminded himself that this was nothing more than the ordinary two-way communicator screen carried a step farther. The booth he was in had its circuitry within its walls, and its multiple screens curved and joined over the inside surface of the booth. The battle transceiver, on the planet, had its circuitry inside, and its screens shaped and joined on its outside surface. The effect was that the commander using the battle transceiver saw things as if he were on the planet, and he was seen by those on the planet as if he were actually there. The defect was that the bulky transceiver on the planet was awkward to move, and constantly in danger from every chance bullet and shell fragment that came its way.
As Wilforce watched, the sergeant made a final adjustment at his box, and abruptly there was sound. The dull clink and scrape of pick and spade reached Wilforce clearly. A voice carried to him from the trenches:
"Hey, the general's ghosting us!"
Wilforce glanced up briefly, and pulled down a small microphone on a slender stalk. "Sergeant," he said, and his voice carried clearly.
The sergeant snapped to attention and saluted.
Wilforce returned the salute and heard the sound of digging slow, as men paused to listen. He said, "Why are these men digging by hand? Is the trencher out of order?"
"No, sir."
"Are all these men being disciplined?" Wilforce's tone was cold.
"No, sir."
"Then why are they digging those trenches?"
"Major's orders, sir."
A dead stillness settled over the clearing.
Wilforce said, "I want those picks and spades put away immediately. Tell the major I want to see that trencher at work out here inside of five minutes. I also want the major and his company commanders to report to me as fast as they can get here."
"Yes, sir." The sergeant stepped back and saluted.
Wilforce returned the salute.
The sergeant faced about and set off at a run. Wilforce watched him scramble down into the ditch around the jutting log walls, climb a ladder against the walls, and pause to salute a lieutenant. There was a brief exchange of words. The lieutenant cast one glance toward Wilforce, and joined the sergeant in a headlong rush toward the inner wall. An instant later, there was the sound of shouted orders, the clank of an engine, and the crash of heavy objects being moved.
The long low trencher rose up behind the wall, a big, roughly ski-shaped grav-carrier supporting it, with three other carriers crosswise to brace the front. At the prow of each carrier bent a sweating technician, while atop the trencher stood the lieutenant, his face pale as he glanced nervously along the line of grav-carriers, and back up over his shoulder at the looming tower. He called out a series of sharp orders to the technician in each carrier, then his voice rose to a scream as one carrier started to sink lower than the rest. Then, heavily, carriers and trencher moved out over the walls, and eased down outside. The trencher trundled off the carriers with a low clank and rumble, then wheeled toward a trench where the men had just stopped digging. The trencher's center section swung down into the earth, and a steadily increasing stream of dirt poured out the discharge to the side. 
Wilforce glanced back at the walls to see a number of officers, very neatly dressed, scramble down the ladder, hesitate at the ditch, then plunge down in and an instant later reappear, several of them reaching out to steady one who stumbled and nearly fell.
As they approached, Wilforce saw that the man who had nearly fallen was the combat group's commanding officer, his face puffy, and his expression blank and hopeless. The officers came to a straggling halt, and saluted.
Wilforce returned the salute, and said, "Major, I have heard that most of these troops are without proper ammunition or charges for their fusion weapons. Is that true?"
There was a distinct lapse of time, then Wilforce saw a faint glimmer in the major's eyes. He started to speak.
Before he could get the words out, a pudgy captain, wearing the bright emblem of the Medical Corps, stepped forward.
"General, this man is ill. As a physician, I must forbid—"
Wilforce glanced at the captain, as a soldier looks at a blood-sucking bug in the bedding just before he squashes it.
The captain hurriedly stepped back out of the way, his teeth clicking together.
The major drew a deep breath, and said shakily, "Sir, it's true."
"I see," said Wilforce, and the silence quickly deepened around him till there was only the rumble of the trencher and the faint rustle of the forest around them. This silence told Wilforce that every man who could was watching, and because of the carnivores in the nearby forest, this situation was dangerous. Wilforce chose his words with care, and spoke so that his voice would carry clearly.
"Major, there are large and dangerous animals in that forest. No doubt the men can hit them with the ammunition they have now. But they can hit them a lot harder with the proper ammunition. I want proxex, impax, and fusion charges issued immediately."
As the major said, "Yes, sir," Wilforce could see the faces of the men turn to glance uneasily toward the forest. This much he had expected. But this was followed immediately by a shout, the glint of a rifle swinging up, and a spatter of gunfire.
Wilforce glanced around to see a brownish form blur across the clearing, then rise in a bound that showed huge forepaws and teeth like bayonets. The fire of machine guns, and of rifles firing almost point-blank, had no effect on the creature that Wilforce could see. A quick glance toward the communications center wall showed him men with fusion rifles looking on in a sort of trance. 
Wilforce brought the microphone to his lips and spoke loud and clearly, "You on the walls, there—burn that thing down!"
Belatedly, the fusion rifles swung up. In the trenches, the men ducked as the carnivore sprang overhead, whirled, crouched, and reached in with its huge paw like a bear scooping fish from a stream. There was an audible snap and crunch of breaking bones, and the huge throat muscles worked under the fur.
Then finally, the dazzling lines of light reached out from the wall. There was a sizzling crack like a thunderbolt striking close at hand. The carnivore jerked, twisted around to claw at its middle, where a dark and widening pool flowed into the earth. Then a searing line of light touched the huge head, there was a spasmodic jerk of paws, and then all that was left was a steaming carcass.
Someone shouted from the far side of the wall, facing the opposite end of the clearing.
Wilforce turned to see the major and his officers standing as if they had been frozen into blocks of ice. He said sharply, "Major, get that ammunition and those fusion charges passed out, and hurry up!"
The major blinked, then suddenly seemed to come to life. He gave rapid orders to his officers, glanced at Wilforce as if he wanted to say something, shook his head slightly, saluted, and set off at an unsteady run for the communications center. A few moments later, the trencher ate its way from the inner line of trenches toward the wall. Men began passing ammunition cans down the ladder to other men in the trench.
Just then, a voice spoke to Wilforce, and it took him an instant to realize that it was Rybalko, saying, "Sir, excuse me—that vanishing ship has been spotted again."
Wilforce slid the microphone up, pressed back the door edge, and stepped out of the transceiver booth, feeling again a momentary disorientation as he glanced around the command center. Then he saw the big viewscreen on the far wall, the planet Bemus III in its lower left corner, and in the center a silvery object like a chopped-off length of giant rod. Wilforce crossed the room to take a closer look.
He studied the big flat-ended object for a moment, noted the pitted look of its surface, and saw what appeared to be a small hatch housing at its far end.
Rybalko said, "Sir, this thing is in orbit around the planet. We've only been watching it for several minutes now, but it vanished twice."
Wilforce, trying to see if what he saw near the far end was a hatch housing, abruptly found himself looking through empty space at a distant constellation. The huge closed cylinder was gone.
Rybalko had a watch in his hand. When the cylinder reappeared, with the abruptness of a projected image thrown on a screen, Rybalko glanced at the watch. "Eight seconds. There doesn't seem to be any pattern."
Wilforce said, "All our instruments show this object?"
"Yes, sir. And its orbit seems perfectly sensible. But all it seems to do is to vanish and reappear. There's been no actual sign of life from it so far."
Wilforce nodded. For a moment, he tried to connect the disappearing ship with the disappearing animals on the planet. But there occurred to him such a host of unlikely theories that he decided to forget all about it. He glanced at Rybalko.
"Both ends of that cylinder are closed?"
"Yes, sir. There are signs of possible openings, but they're shut now."
Wilforce glanced at the cylinder again. Its blocky shape suggested to him that it was probably not intended for use in a planet's atmosphere. It might be—perhaps—an interplanetary cargo carrier. The apparent invisibility of the ship might be due to extremely well-designed counter-detection apparatus. Assuming it had, for some unknown reason, been left in orbit around this planet, it could have remained there for thousands of years with little noticeable change. And the destroyer that crash-landed on Bemus III had collided with something. It seemed reasonable to think it had collided with this cylinder, had heavily jarred the counter-detection apparatus, and caused a malfunction that produced the alternating visibility and invisibility.
Wilforce turned to Rybalko, and said, "We'll have to see if that thing can be boarded. It's just possible that this might be the loose end of the knot."
Rybalko turned to the communicator to repeat the boarding order to the task force commander.
As Wilforce again turned to glance at the unchanging battle screen, a call came in from Pick.
"Here's something queer," said Pick. "Some of my men have been finishing up a check of the settlements. They've found a few partly-chewed scraps of clothing, paper, and so on, plus droppings containing metal snap fasteners, identification tags, and other metal items, which pretty well bolster the theory that the carnivores attacked and actually ate the colonists, and the herbivores ate the food stocks and records. But some of the metal identification tags, chains, and other items were in unburied droppings, exactly typical of the Bemus herbivores we've seen so far."
"The colonists could have taken off their tags and left them in the pockets of their clothing."
"Would they have taken out their dental fillings and put them in their pockets?"
Wilforce stared, then said slowly, "Dogs don't bury their droppings. They're carnivores."
"True, but everything we've found so far suggests catlike forms that lie in wait, not doglike animals that run down their prey. And it's important to a catlike animal to keep the herbivores in the vicinity unaware that it's there. This business strikes me as very peculiar, and it's not the only peculiar thing."
"What else?"
"All the settlements have big barbecue pits. Now we find from the remains of weeds buried under the dirt from these pits, from the size of weeds growing atop the dirt, from the ashes in the pits, and from the condition of the pit's big stakes, that they were dug recently and only used once—around the time the attack was made on the settlements."
Wilforce went to bed still turning this problem over in his mind. Early the next morning, he came wide awake, and, for an instant, everything fitted together in a complete picture.
Wilforce swung to a sitting position on the edge of his cot. Already, the thoughts were slipping away, and carefully he held his mind nearly blank, trying to grope back along the mental associations to the pattern of ideas that had been in his mind the instant before he came fully awake. Gradually, it all came back to him, and he saw the puzzle on Bemus III fit together like the steel hooks, jaws and springs of a powerful trap.
Wilforce went over his thoughts a bit at a time, carefully checking each connection, till he was sure it fitted together in a consistent whole. Now he wondered how he could ever have missed it. He washed, dressed quickly, and started down the corridor to the command center. He turned a corner and a junior communications officer came out a door and said, "Sir, excuse me, could you come in here a minute?"
"What is it?"
"It's the screen the Pioneers set up so we could watch the destroyer, sir. We've got something funny here."
Wilforce said, "All right. Let's see it."
The communications officer quickly led the way into a darkened room, where a technician sat hunched at a screen. Wilforce looked over his shoulder to see a dim corridor in the crash-landed destroyer. In the foreground was an air-circulation duct. As Wilforce leaned closer, he saw a faint movement, then a small shadowy thing that squeezed under a corner of the mesh over the duct opening and dropped to the floor. There was a swift scurry down the corridor, then another small thing moved in a long bound. There was a brief struggle, then silence, and finally a faint crunch. Another shadow slid out the duct.
Wilforce said, "How long has this been going on?"
"Ever since they carried that big tomcat around the corner into the food storeroom. These things have been popping out the ventilator right and left."
"I see." Wilforce turned to the communications officer. "Get Mr. Pick for me on another screen, and hurry."
"Yes, sir."
The officer went out, and Wilforce turned to glance at the screen. On it, nothing moved. The corridor appeared to be empty. He said to the technician, "We aren't transmitting sound, are we?"
"No, sir."
"Have you seen any other animals beside these small ones?"
"Sir, I could have sworn something the size of a rat went by the other night. But it was moving fast, and I haven't seen anything like it since."
"Did it come out of that ventilator?"
"No sir. It streaked down the corridor well over to the side."
The door opened. "Sir, we'll have Mr. Pick in just a moment."
Wilforce said, "Switch the call to the command center. I'll want General Rybalko to see it, if possible."
"Yes, sir."
Wilforce went to the command center, observed that the battle screen continued to show nothing of interest, and then saw the big wall screen, lit to show the huge cylinder, now surrounded by small spaceboats. There was a round opening in the far end of the cylinder where Wilforce thought he had seen a hatch. He looked at the cylinder with a frown, then glanced around as a communicator switched on. Pick was on the screen, tired and scowling.
Wilforce described what he'd just seen.
Pick said, "Just a minute. I'll find out whether that cat's caught anything."
Wilforce snapped on another communicator, and called Davis, who appeared on the screen rumpled but alert. Wilforce said, "Has the Forty-second had any more trouble?"
"Nothing serious, sir. Every now and then, something charges out of the forest and gets cut to pieces before it can do anything. The only trouble is rats and hallucinations."
"Rats?"
"Yes, sir. A kind of furtive vicious rat has turned up that feeds on the remains of the carnivores and any other flesh it can sink its teeth in. There have also been reports of things something like hyenas, but there are a lot more of these rats."
"What was that about hallucinations?"
"The nervous strain down there must be pretty severe. The men are probably in no real danger now, but the thought of those monsters springing out of the forest any moment, and the constant watch that has to be kept—Well, some of the men think they've seen chunks of carnivores they've shot get up and walk away."
"You have your colonel of Scouts in charge?"
"Yes, sir."
"Did you get that medical officer out of there?"
"Yes, sir. Incidentally, sir, he cracked up. He tried to shoot himself, and bungled the job."
Wilforce said, "Get a transport into position. I may want to take the Forty-second off that planet entirely."
"Yes, sir."
Wilforce blanked the screen and turned to see Pick on the other screen, a deep scowl on his face. Pick said, "That tomcat has eaten, all right. He's filled out like a barrel. He's in there dozing, and purring like a gasoline engine. There are half a dozen tails spread out around him, and the rear half of something like a cross between a rat and a weasel."
Wilforce said, "Get that half a rat, or whatever it is, and watch it. See that it doesn't get away."
Pick looked blank. "It's dead. How's it going to get away?"
"Never mind that. Watch it."
Pick's face screwed up in thought. He nodded. "All right. We'll watch it."
"Do you expect to need any help from the Forty-second?"
Pick shook his head. "I don't think we'll need any help. The simple fact is something made us jumpy. We're still jumpy. But now we're used to it."
Wilforce nodded in understanding. "Suppose for the time being you keep your men under cover, and use the probes to scout and observe."
"All right" said Pick. "Have you figured out what's going on here?"
"I'm not absolutely sure," said Wilforce. "But it seems to me we've got one foot in the biggest biological trap ever constructed. Now, I've got to see if this is true, and if so, how we can smash the trap." After this call, Wilforce got Rybalko.
"Sir?" said Rybalko.
"Balky, I want three sub-nuclear triggers checked out. I don't think we'll have to use them, but I want them ready. And have the reflectors ready to focus on Bemus III, so that a given word, we can roast the planet."
"Yes, sir," said Rybalko.
Wilforce called Davis to take the Forty-second Combat Group off the planet. Then he had his flagship's communications center get the nearest headquarters of the Planet Certification Authority, which had made the original survey of Bemus III. He asked a single pointed question, and after a considerable delay, he received the answer: "General, there have been no restrictions on travel to Bemus III since the planet was certified for colonization."
Wilforce got the task force commander, and asked, "What have you found out about that cylinder?"
"Sir, as nearly as we can tell, it's nothing but an extremely heavy protective housing. Inside it, there's a missile armed with what we're pretty sure is a sub-nuclear trigger. Evidently someone wanted to be able on short notice to turn that planet into a brilliant star."
"How is the missile released from the cylinder?"
"The ends of the cylinder are hinged to swing open like double doors, sir."
"What causes the missile to be launched?"
"So far, sir, we don't know."
"All right. There may be more of these missiles in undetectable housings. If so, we want to know about them. Check the most likely simple orbits, on the assumption that a number of missiles were used in case one failed."
"Yes, sir."
Wilforce turned to see Rybalko talking to a tall, tense-looking man Wilforce recognized as Dr. Traeger, his chief medical officer. Traeger was speaking insistently, and Rybalko was frowning. Wilforce walked over.
"What is it, Traeger?"
"General, Evaluation has been trying to decide whether the smaller herbivores on Bemus III are offspring of the big, mammoth-like croppers that Planet Certification thought were becoming extinct."
"Yes?"
"Well, several of my colleagues and I tried to dissect a medium-sized herbivore, to see how similar the internal structure was to the cropper Planet Certification reported dissecting."
"What did you find out?"
"General, we had a trying time. The exposed tissues exuded white droplets. These cohered to form a tough membrane through which we could see absolutely nothing. We cut off a number of large blocks of muscle tissue to study this process. Nearly every block was quickly covered with a tough membrane. We examined the blocks at intervals and found that the enclosed tissues became soft and viscous. Layers of large hollow cells built up behind the membrane, and the internal temperature rose sharply. A reorganization of the substance of the tissues began to take place."
"To form what?"
Traeger drew a deep breath, looked directly at Wilforce and said unhappily, "To form the outlines of a small carnivore."
"An embryo?"
"No, not an embryo. I don't know how to explain it except to say that it reminded me of the precipitate that forms when a photographic plate is exposed. No doubt the mechanism is completely different, but that is what it looked like."
"This happened in blocks of muscle tissue?"
"Yes, sir." 
"How would the animal find enough of the right chemical substances to form its teeth, bone structure, brain, and so on?"
Traeger shook his head. "General, I don't think it would find enough. But the report on Planet Certification's original dissection mentions a chain of complex nerve cells of unknown function, paralleling the main skeletal framework. At intervals, there were large ganglia, again with no known function. If we had cut through the entire limb, instead of merely taking blocks of muscle tissue, some of the blocks would have included these large ganglia as well as bone. Then the development might have been complete. As it was, the outlines became less distinct in the last blocks we examined. But the important point is that it happened at all."
Wilforce said, "Did the Planet Certification report mention anything like this?"
"No, sir. Nothing. It may be that the larger and older animals take longer to regenerate. Planet Certification also used the latest methods of tissue preservation, which weren't available to us."
"What happened to the animal you cut the muscle tissue from?"
"Well, by this time we'd seen what I've just mentioned, and were getting a little uneasy. We were doing the dissection in an improvised lab on one of Evaluation's scout ships. The idea was incredible, but incredible or not, we didn't care to find ourselves suddenly at close quarters with one of those carnivores that had shown up down on Bemus III. We switched to another ship, so we could watch what happened next by communicator. We needn't have hurried. Some ten hours later, there were convulsive movements beneath the membrane that formed under the fur and over the cut parts of the animal. The membrane ripped open, and a medium-sized carnivore, its fur wet and clinging, climbed out, crouched, and ate the membrane."
Wilforce nodded slowly. "And in the chunks of muscle tissue, you said small incomplete carnivores had formed? Not herbivores, but carnivores?"
Traeger said, "We could see the beginning of claws and teeth, and the shape of the head. They were carnivores. I know how it seems, but there it is. The whole thing's impossible."
"Never mind that," said Wilforce. "If it happened, it's possible. Nature isn't bound to one single procedure. What did this large carnivore do after it ate the membrane?"
"It looked around, ate the remains of the blocks of muscle tissue, then curled up and went to sleep. After a short sleep, it woke up, sniffed the fur the membrane had formed under, tipped the communicator stand over, and that was the last we saw."
Traeger shrugged helplessly.
"All right. Now we have to find out more. What we might do now is pack the landing boat's air lock with a variety of meat, flour, paper, and other organic materials and foodstuffs, put in a time-opener for the inner air-lock door, and another communicator behind heavy mesh, and see what happens when that carnivore gets at the food."
Traeger said, "I was thinking of something like that. I'll let you know as soon as we find out anything more."
Good."
Traeger turned to go out, and Wilforce noticed Rybalko standing nearby with a deep frown on his face. Rybalko looked at Traeger's retreating back as an officer might look at a subordinate who reported, "Sir, there's a stream in front of us, it's wide and deep and it's flowing uphill at a good clip."
Rybalko turned to Wilforce and said, "Sir, I don't quite know about Traeger. I don't exactly believe that."
Wilforce said, "Don't be too sure. Back on Earth, if I remember correctly there are things called 'oysters'—small water animals protected by two hard shells—that grow in large number in 'oyster beds' and are used for human food. There are also creatures called 'starfish.'
"Now," said Wilforce, "the starfish likes to eat oysters, just as people do. When the starfish finds an oyster, it grips the oyster's shell with sucking stalks on the underside of its limbs, and eventually forces the oyster's shell open. Then it squirts in a digestive fluid, and eats the oyster. Naturally, people don't care to find these starfish prowling through the oyster beds. At one time, whenever they could, they used to chop the starfish to pieces."
Rybalko nodded approvingly.
Wilforce added, "They did this until they discovered that a mere single arm of the starfish, if it included enough of the center, could regenerate a complete new starfish."
Rybalko looked blank. Then he said, "This happened on Earth?"
"It did. Quite a while ago, too. Our problem here has been compounded, multiplied, and raised several powers higher, so that we have what you might call a 'star tiger' to deal with. But even that is only about half of it. And we have to find an answer quickly."
During the rest of the morning, Wilforce received a number of calls. Pick, perspiring heavily, told Wilforce that the half-rat from the storeroom had grown some kind of white film, out of which had emerged a little vicious furtive thing that looked like a shrew. This thing hid under every scrap of cover, and tore a chunk out of the forefinger of a pioneer who tried to uncover it. Pick mentioned this in the defensive manner of a man who doesn't expect to be believed.
Immediately after this, Davis called, to cautiously reveal, with many roundabout expressions, that he had seen by battle transceiver a kind of big carnivore climb out through the whitish membrane around a chunk of carcass down on Bemus III. The soldiers were already so used to this that they shot the creature all over again as it emerged from the membrane. Other than this, the Forty-second had lifted from the planet without incident, but Davis was at pains to get the significance of the carnivore across to Wilforce.
No sooner was this call ended than one came in from Evaluation, and a scholarly biologist explained Traeger's information to Wilforce all over again, with many homely analogies to make it easier for the layman to understand. He dwelt heavily on the caterpillar that spins a cocoon to emerge a moth, and nothing Wilforce could do would stop him till he ran through all the details.
In a bad mood, Wilforce called back to have Davis hold the Forty-second's transport away from his other troops, and also to have to have the men be on the lookout for small mouse- or shrew-like creatures on the transport. Davis nodded and started explaining all over again about the carnivore coming out of the chunk of carcass. Wilforce saw little flecks dance before his eyes, and Davis hastily changed the subject.
That afternoon the task force commander called to say he had located another cylinder.
"How did you find it?"
"We figured they used three, to be reasonably sure at least one would work, and spaced them evenly about the planet. We already could make a pretty fair guess how the orbit of the one we'd found had been when the destroyer swiped it, so it seemed logical to sweep one hundred twenty degrees back with a flat pattern of reconnaissance torpedoes. This could have taken a long time, but we guessed right, and pretty soon one of the torpedoes banged into something that didn't show up on the detectors."
Good," said Wilforce. "Tag that one, then see if you can find another."
"Yes, sir."
Wilforce blanked the screen, thinking that there might well be half-a-dozen or more of the cylinders, but that there was no point discouraging his men by mentioning things like that.
Dr. Traeger now appeared on the screen to say, "General, we did as you suggested. We ran a sealed boarding tunnel to the scout ship, and filled the air lock with meat and other edibles and organic materials."
"What happened?"
"When the timer worked the inner lock door mechanism, the carnivore gorged on the meat, then went to sleep. We could see into the ship, and the skin and fur was gone, so evidently it had eaten that. Well, twenty minutes after gorging on the meat, it drank a great deal of water. It curled up very tightly, and its breathing became labored, as if it was struggling up a steep hill. Then the breathing gradually slowed. Three hours later the animal got up, and we could see that the form of its head, teeth, and body in general had altered to match that of the usual Bemus herbivore. It walked over to the air lock, ate up twenty-five pounds of flour, ten pounds of sugar, a ream of yellow scratch paper, a ball of twine, a uniform shirt, a pair of leather boots and a plastic ruler. Then it went back to sleep."
Wilforce nodded, and said, "Now what I want to know is, how does it all fit together? Kill a Bemus animal and it turns into one or more savage carnivores. Feed the carnivore and it becomes an herbivore. I wonder if it forms sort of a scale, with the mammoth-like cropper on top, and some other creature on the bottom."
Traeger said, "I should think the lower limit for this creature would be the minimum size capable of efficiently carrying the biological control mechanism that reorganizes the tissues."
Wilforce said, "I imagine Pick can help us on that. He already has one about the size of a shrew. I'll call him."
Pick was on the screen a few minutes later. Wilforce said, "Pick, do you still have that shrew?"
"We've got the thing. We aren't happy with it."
"I want you to kill it."
"It will be a pleasure. But what if it dies, and later on half-a-dozen carnivorous grasshoppers pop out?"
"That's exactly what we want to find out. We want to know just how small the thing will get."
"We'll find out for you."
The screen blanked, and Rybalko came over to say, "Sir, the Forty-second has searched its transport. A number of men think they saw small furtive animals, but there's nothing definite."
Wilforce said, "Have them lay another transport alongside, bridge the air locks, and cross over one at a time. They'll have to strip before leaving one ship, and receive a new issue of clothing as they enter the other. Then we can pump the transport's air back into its tanks, send some men back through in spacesuits to search, and eventually find out if there are any animals on board."
In the next few days, spacesuited searchers found a number of small mouse-and shrew-like animals on the transport. Now that everyone had an idea what to look for, one thing rapidly led to another.
From Traeger, Evaluation got the first solid details of the life cycle of the carnivore. With this clue to go on, they went back over a number of previous observations, and found that what they had dismissed as irrational made sense after all. Wilforce now got a flood of information that would have cleared everything up if he had gotten it sooner—but Evaluation had been afraid to give it to him because Evaluation knew it didn't make sense.
Pick called to say that the shrew was thoroughly dead, it failed to show any signs of reviving, and it was getting unpleasant to keep the thing around. Pick, therefore, buried the shrew, and Evaluation, now ready to believe anything, kept a wary eye on the grave.
Meanwhile, a sound engineer, going over a film of the animals in the corridor of Pick's ship, discovered that the furtive "mouse," when attacked, gave terrified squeals—in a pitch too high for the human ear to hear. He suggested that these just inaudible noises, repeated over and over, accounted for the uneasiness of Pick and his men, and might also be used to test for the presence of the animals.
As Wilforce and Rybalko were going over this information, the task force commander called to say that he had found two more of the huge cylinders. One contained another sub-nuclear trigger. The other contained the bulk of the control mechanism, designed to ignore an object that went down to the planet, but to send a signal that would trip off the triggers if anything tried to come up from the planet.
Wilforce said, "Why didn't it work?"
"Because two metal strips had to slide over one another under light pressure. Apparently, they had been there so long the atoms of the metal had interpenetrated. The strips didn't move. We've dismantled the whole thing, just in case."
"Was the mechanism purely automatic?"
"Yes, sir. But there was a manual control, too. This cylinder also had an arrangement for internal heating, plus a cot, and a desk with a little statuette."
"A statuette?"
"Apparently some kind of reminder, sir. It showed a carnivore, its sides all swollen out, with what looked like an empty pair of boots and a hat nearby."
Wilforce said, "Keep looking. There may be more of those triggers, and there should be a separate warning system around somewhere."
When this call was finished, Wilforce sat back for a moment, then had his communications center get in touch with the chief of colonization. A strongly built, firm-jawed man promptly appeared on the screen. He said, "I've been studying staff reports on Bemus III since Larssen sent out his alarm. Is it as bad as it seems?"
"Sir," said Wilforce, "in my opinion, it's a terrific nuisance, and a headache of the first magnitude. I don't think it should be anything worse."
The chief of colonization looked surprised, and picked up a sheet of paper. "I have here an analysis that ends up as follows: ' . . . Thus small furtive Bemus creatures must already have left the planet on supply ships. They have infested an unknown number of other ships, supply centers, and almost certainly, planets. It is impossible to alter the traffic flow to prevent further infection, because we don't know where they are already. Any one of these creatures may grow larger, suffer successive 'deaths,' and by an unprecedented type of reproduction come to populate any planet where it is introduced. The small creatures are furtive and hard to find. The large herbivores eat immense quantities of food. The large carnivores are deadly.'"
The chief of colonization scowled. "I am no pessimist. And I don't believe in being hypnotized by difficulties. Still—are the facts I've just mentioned correct?"
"Yes, sir."
"But you think it's just a headache?"
Wilforce nodded. "It seems to me to be part of the price we pay for colonizing new star systems. If we break a trail through the jungle, some fine day, a tiger will lie in wait beside it. That doesn't mean the trail is no good. It only means that now we have to figure out how to dispose of the tiger. It's been like this since back before history began. The caveman discovers fire; that's fine—but now he gets burnt. He wants light at night, and invents the lamp; it gives light, and it also flickers and smokes up the cave. He stores food for the winter; rats get in it. A problem solved leads to one unsolved. Now we find ourselves with a big trail—and a big tiger beside it."
"But how do we dispose of this one?"
"Well, most big problems break down into a number of smaller problems. Here, we have three of these smaller problems. First—the source of the trouble—the animals on Bemus III. Second, their ability to stow away and travel on our spaceships. Third, any new colonies of the animals on other planets.
"To start with," said Wilforce, "we can ring Bemus III with sub-nuclear triggers, set up a warning network to keep ships away, and, if necessary, destroy the planet.
"As for travel by spaceship, it's the small, furtive animals that do this. We might not be able to ferret them out ourselves, but we can find animals to do it for us—the cat, for instance. As a check, we can put in devices to spot that high-pitched squeal the animal gives when it's caught."
The chief of colonization nodded. "Good so far. But what do we do if it gets onto a planet?"
"That's harder. Evaluation has just tried poisons, for instance. The carnivores don't touch it, and herbivores 'die' and reconstitute themselves as carnivores. All we've seen so far shows it's not much use just to kill them. The colonists put up special barbecue pits. Evidently they killed the animals for a feast to celebrate their tenth anniversary on the planet. The captain of the crash-landed destroyer told me his men had plenty of fresh meat, so apparently they were killing them. The Forty-second had to hunt part of its food in the forest. In each case, we got misery and disaster as a result. Chance accidents, such as lightning, drowning, the fall of limbs in windstorms, were evidently enough to create an occasional monster carnivore, and keep the colonists constantly on edge when they didn't kill the things themselves. So I don't think we want to kill them."
"If we don't kill them, what do we do?"
"Feed them. Every time there's been an attack on the herbivores, hosts of carnivores have appeared, only to vanish by the time anyone got here to investigate. The carnivores will eat the herbivores if there's nothing else handy. They'll eat chunks of dead carnivores. They very quickly become herbivores, and they will eat all kinds of things. So if we have emergency food stocks ready, we can dump them in chosen areas on any infested planet, and let the creatures gorge themselves. Since they eat all kinds of things, the food stocks needn't be expensive."
"You're thinking—instead of carnivores and little scattered furtive creatures, we'll end up with placid herbivores?"
"Yes, sir."
"Then what?"
"If nothing else, we can prod them into a cargo carrier, and sling the whole works into the nearest sun. It's crude, but it ought to work."
The chief of colonization nodded absently, "Don't let the crudity of it bother you, as long as it works." He frowned. "What about those cylinders?"
"What we've seen so far indicates they're ancient. Evidently some other race ran into this problem long ago, arrived at roughly the same solution we've thought of, and has since died out, or somehow moved on. The Bemus creatures remain locked in a sort of fluid status quo."
The colonization chief was staring off at something out of the range of vision. Suddenly he snapped his fingers. "I think I see what to do. Of course, the Interstellar S.P.C.A. may let out a howl such as was never heard in all recorded history. Still—"
* * *
Some months later, the two men were on Donak IV, a frontier planet that had reported an outbreak of Bemus creatures. Moving barriers of charged wires prodded herds of the monster herbivores across a causeway to a cluster of cylindrical metal towers in the middle of a lake. There appeared to be some sort of grim production line in progress.
From where Wilforce stood, he could see the animals go around a corner, get shot by men with fusion guns, then picked up by mechanical loaders, and dumped onto a conveyer belt which promptly carried them down out of sight.
There came a sound of rushing water, and an electrified barrier switched the flow of Bemus creatures to another tower.
Near the tower were several buildings, one bearing the sign: "TANNERY."
The chief of colonization nodded approvingly. "Very satisfactory arrangement. We stuff a load of monsters in that tower, fill it up with water, and let them evolve through whatever grisly changes they want to. It doesn't matter whether they turn into super-tigers, medium-sized carnivores, or little carnivores—they don't live without air. And that situation keeps them too busy to eat up their furs after they finish a change."
A grav-carrier lifted a load of hides from one of the towers toward the building marked "Tannery." A small hole in the side of a tower opened and spat into the lake several dozen limp mouse- and shrew-like animals, which were promptly snapped up by lean, sharp-toothed fish swimming around.
The chief of colonization glanced at Wilforce and smiled. "Well," he said, "that problem seems to be solved—but who knows what may happen next?"
"That's right" said Wilforce. "Man's special skill is solving problems. But the one he can't solve—is the problem of having problems."