by Hal Clement
Why no one got the answer then will always remain a mystery; but the engineer was answered by nothing but half a dozen thought expressions more or less hidden in space helmets. He looked around hopefully for a moment, then shrugged his shoulders. “Looks like we’ll just have to puzzle around and hope for the best,” he concluded. “Jack and Don might as well go back to their own snooping—and for Heaven’s sake, if you get any more ideas, come a-runnin’.”
After glancing at Grant for confirmation of the suggestion, Preble and Stevenson left the engine room to continue their interrupted tour. “I wonder if the upper section behind the control room is sealed,” remarked the chemist as they entered the darkness of the corridor. “I think we’ve covered the bow fairly well.” Preble nodded; and without further speech they passed through the control chamber, glancing at the board which had given Grant and McEachern such trouble, and found, as they expected, ramps leading up and down opening from the rear corridor just as one entered.
They stayed together this time, and climbed the star-board spiral. The door at the top opened easily, which was some relief; but the hallway beyond was a disappointment. It might have been any of the others already visited; and a glance into each of the rooms revealed nothing but bare metal gleaming in the flashlight beams, and dust-covered floors. The keel corridor was also open; but here was an indication that one, at least, of the rooms had been used for occupancy rather than cargo.
Stevenson looked into it first, since it was on the side of the corridor he had taken. He instantly called his companion, and Preble came to look at the object standing in the beam of the chemist’s light.
It was a seat, identical to the one in the control chamber—a mound of metal, with five deep groove; equally spaced around it. The tiny reflected images of the flashlights stared up from its convex surfaces like luminous eyes. None of the other furniture that had characterized the room in the central bow corridor was present but the floor was not quite bare.
Opposite each of the five grooves in the seat, perhaps foot out from it, a yard-long metal cable was neatly welded to the floor. A little farther out, and also equally spaced about the seat, were three more almost twice a long. The free end of each of the eight cables was cut of cleanly, as though by some extremely efficient instrument the flat cut surfaces were almost mirror smooth. Stevenson and Preble examined them carefully, and then looked at each other with thoughtful expressions. Both were beginning to get ideas. Neither was willing to divulge them.
There remained to explore only the stern engine room and the passage leading to it, together with the room; along the latter. They had no tools with which to remove a specimen of one of the cables, so they carefully noted the door behind which the seat and its surroundings has been found, and climbed once more to the central deck Before making their last find, they had begun to be bored with the rather monotonous search, particularly since they had no clear idea of what they were searching for without it, they might have been tempted to ignore the rooms along the corridor and go straight to the engine room. Now, however, they investigated every chamber carefully; and their failure to find anything of interest was proportionally more disappointing.
And then they reached the engine-room door.
Flashlights swept once over the metal surface, picking out three disks with their inset triangular blocks, as the men had expected, but the coppery reflection from two of the blocks startled them into an instant motionlessness. Of the three seals, they realized, only one—the uppermost—was locked. It was as though whoever had last been in the room had left hastily—or was not a regular occupant of the ship.
Preble quickly reversed the remaining block, and unscrewed the three disks; then the two men leaned against the door and watched it swing slowly open. Both were unjustifiably excited; the state of the door had stimulated their imaginations, already working overtime on the material previously provided. For once, they were not disappointed.
The light revealed, besides the tanks, converters, and tube breeches which had been so obvious in the forward engine room, several open cabinets which had been mere bulges on the walls up forward. Tools and other bits of apparatus filled these and lay about on the floor. Light frameworks of metal, rather like small building scaffolds, enclosed two of the axial tube breeches; and more tools lay on these. It was the first scene they had encountered on the ship that suggested action and life rather than desertion and stagnation. Even the dust, present here as everywhere, could not eradicate the impression that the workers had dropped their tools for a brief rest, and would return shortly.
Preble went at once to the tubes upon which work had apparently been in progress. He was wondering, as he had been since first examining one, how they were opened for servicing. He had never taken seriously Cray’s remark that it might have been done from outside.
His eye caught the thing at once. The dome of metal that presumably contained the disintegrator and ionizing units had been disconnected from the fuel tank, as he had seen from across the room; but a closer look showed that it had been removed from the tube, as well, and replaced somewhat carelessly. It did not match the edges of its seat all around, now; it was displaced a little to one side, exposing a narrow crescent of flat metal on each of the two faces normally in complete contact. An idea of the position can be obtained by placing two pennies one on the other, and giving the upper one a slight sideward displacement.
The line of juncture of the two pieces was, therefore, visible all around. Unfortunately, the clamping device Preble expected to find was not visible anywhere. He got a grip—a very poor one, with his gloved hand—on the slightly projecting edge of the hemisphere, and tried to pull it free, without success; and it was that failure which gave him the right answer—the only possible way in which an air-tight and pressure-tight seal could be fastened solidly, even with the parts out of alignment, with nonmagnetic alloys. It was a method that had been used on Earth, though not on this scale; and he was disgusted at his earlier failure to see it.
Magnetism, of course, could not be used so near the ion projectors, since it would interfere with the controlling fields; but there was another force, ever present and available—molecular attraction. The adjoining faces of the seal were plane, not merely flat. To speak of their accuracy in terms of the wave length of sodium light would be useless; a tenth-wave surface, representing hours of skilled human hand labor, would be jagged in comparison. Yet the relatively large area of these seals and the frequency with which the method appeared to have been used argued mass production, not painstaking polishing by hand.
But if the seal were actually wrung tight, another problem presented itself. How could the surfaces be separated, against a force sufficient to confine and direct the blast of the ion rockets? No marks on the breech suggested the application of prying tools—and what blade could be inserted into such a seal?
Stevenson came over to see what was keeping Preble so quiet, and listened while the latter explained his discovery and problems.
“We can have a look through these cabinets,” the chemist remarked finally. “This seems to fit Sorrell’s idea of a tool-requiring job. Just keep your eyes and mind open.”
The open mind seemed particularly indicated. The many articles lying in and about the cabinets were undoubtedly tools, but their uses were far from obvious. They differed from man-made tools in at least one vital aspect. Many of our tools are devices for forcing: hammers, wrenches, clamps, pliers, and the like. A really good machine job would need no such devices. The parts would fit, with just enough clearance to eliminate undesired friction—and no more.
That the builders of the ship were superb designers and machinists was already evident. What sort of tools they would need was not so obvious. Shaping devices, of course; there were planers, cutters, and grinders among the littered articles. All were portable, but solidly built, and were easily recognized even by Preble and Stevenson. But what were the pairs of slender rods which clung together, obviously magnetized? What w
ere the small, sealed-glass tubes; the long, grooved strips of metal and plastic; the featureless steel-blue spheres; the iridescent, oddly shaped plates of paper-thin metal? The amateur investigators could not even guess, and sent for professional help.
Cray and his assistants almost crooned with pleasure as they saw the untidy floor and cabinets; but an hour of careful examination and theorizing left them in a less pleasant mood. Cray conceded that the molecular attraction theory was most probably correct, but made no headway at all on the problem of breaking the seal. Nothing in the room seemed capable of insertion in the air-tight joint.
“Why not try sliding them apart?” asked Stevenson. “If they’re as smooth as all that, there should be no difficulty.”
Cray picked up a piece of metal. “Why don’t you imagine a plane through this bar, and slide it apart along that?” he asked. “The crystals of the metal are practically as close together, and grip each other almost as tightly, in the other case. You’ll have to get something between them.”
The chemist, who should have known more physics, nodded. “But it’s more than the lubricant that keeps the parts of an engine apart,” he said.
“No, the parts of one of our machines are relatively far apart, so that molecular attraction is negligible,” answered the machinist. “But—I believe you have something there. A lubricant might do it; molecules might conceivably work their way between those surfaces. Has anybody noticed anything in this mess that might fill the bill?”
“Yes,” answered Preble promptly, “these glass tubes. They contain liquid, and have been fused shut—which is about the only way you could seal in a substance such as you would need.”
He stepped to a cabinet and picked up one of the three-inch long, transparent cylinders. A short nozzle, its end melted shut, projected from one end, and a small bubble was visible in the liquid within. The bubble moved sluggishly when the tube was inverted, and broke up into many small ones when it was shaken. These recombined instantly when the liquid came to rest, which was encouraging. Evidently the stuff possessed a very low viscosity and surface tension.
Cray took the tube over to the breech which had been partly opened and carelessly closed so long ago, held the nozzle against the edge of the seal, and, after a moment’s hesitation, snapped off the tip with his gloved fingers. He expected the liquid to ooze out in the asteroid’s feeble gravity, but its vapor pressure must have been high, for it sprayed out in a heavy stream. Droplets rebounded from the metal and evaporated almost instantly; with equal speed the liquid which spread over the surface vanished. Only a tiny fraction of a percent, if that, could have found its way between the surfaces.
Cray stared tensely at the dome of metal as the tube emptied itself. After a moment, he dropped the empty cylinder and applied a sideways pressure.
A crescent, of shifting rainbow colors, appeared at the edge of the seal; and the dome slowly slid off to one side. The crescent did not widen, for the lubricant evaporated the instant it was exposed. Preble and Stevenson caught the heavy dome and eased its mass to the central catwalk.
The last of the rainbow film of lubricant evaporated from the metal, and the engineers crowded around the open breech. There was no mass of machinery inside; the disintegrators would, of course, be within the dome which had been removed. The coils which generated the fields designed to keep the stream of ionized vapor from contact with the tube walls were also invisible, being sealed into the tube lining. Neither of these facts bothered the men, for their own engines had been similarly designed. Cray wormed his way down the full length of the tube to make sure it was not field failure which had caused it to be opened in the first place; then the three specialists turned to the breech which had been removed.
The only visible feature of its flat side was the central port through which the metallic vapor of the exhaust had entered the tube; but application of another of the cylinders of lubricant, combined with the asteroid’s gravity, caused most of the plate to fall away and reveal the disintegrator mechanism within. Preble, Stevenson, Grant, and McEachern watched for a while as pieces of the disintegrator began to cover the floor of the room; but they finally realized that they were only getting in the way of men who seemed to know what they were doing, so a gradual retreat to the main corridor took place.
“Do you suppose they can find out what was wrong with it?” queried Stevenson.
“We should.” It was Cray’s voice on the radio. “The principle of this gadget is exactly like our own. The only trouble is that they’ve used that blasted molecular-attraction fastening method everywhere. It’s taking quite a while to get it apart.”
“It’s odd that the technology of these beings should have been so similar to ours in principle, and yet so different in detail,” remarked Grant. “I’ve been thinking it over, and can’t come to any conclusion as to what the reason could be. I thought perhaps their sense organs were different from ours, but I have no idea how that could produce such results—not surprising, since I can’t imagine what sort of senses could exist to replace or supplement ours.”
“Unless there are bodies in the sealed-off corridor and rooms, I doubt if you’ll ever find the answer to that one,” answered Preble. “I’ll be greatly surprised if anyone ever proves that this ship was made in this solar system.”
“I’ll be surprised enough if anyone proves anything at all constructive about it,” returned Grant.
Cray’s voice interrupted again.
“There’s something funny about part of this,” he said. “I think it’s a relay, working from your main controls, but that’s only a guess. It’s not only connected to the electric part of the business, but practically built around the fuel inlet as well. By itself it’s all right; solenoid and moving core type. We’ve had it apart, too.”
“What do you plan to do?” asked Grant. “Have you found anything wrong with the unit as a whole?”
“No, we haven’t. It has occurred to me that the breech was unsealed for some purpose other than repair. It would make a handy emergency exit—and that might account for the careless way it was resealed. We were thinking of putting it back together, arranging the relay so that we can control it from here and test the whole tube. Is that all right with you?”
“If you think you can do it, go ahead,” replied Grant. “We haven’t got much to lose, I should say. Could you fix up the whole thing to drive by local control?”
“Possibly. Wait till we see what happens to this one.” Cray moved out of the line of sight in the engine-room doorway, and his radio waves were cut off.
Stevenson moved to the doorway to watch the process of reassembly; the other three went up to the control room. The eeriness of the place had worn off—there was no longer the suggestion of the presence of the unknowable creature who had once controlled the ship. Preble was slightly surprised, since it was now night on this part of the asteroid; any ghostly suggestions should have been enhanced rather than lessened. Familiarity must have bred contempt.
No indicator lights graced the control panel. Grant had half hoped that the work in the engine room might have been recorded here; but he was not particularly surprised.
He had given up any hopes of controlling the vessel from this board, as his remark to Cray had indicated.
“I hope Cray can get those tubes going,” he said after a lengthy silence. “It would be enough if we could push this ship even in the general direction of Earth. Luckily the orbit of this body is already pretty eccentric. About all we would have to do is correct the plane of motion.”
“Even if we can’t start enough tubes to control a flight, we could use one as a signal flare,” remarked Preble, “Remember, the Mizar is in this sector; you once had hopes of contacting her with the signal equipment of this ship, if you could find any. The blast from one of these tubes, striking a rock surface, would make as much light as you could want.”
“That’s a thought,” mused Grant. “As usual, too simple for me to think of. As a matter of fact,
it probably represents our best chance. We’ll go down now and tell Cray simply to leave the tube going, if he can get it started.”
The four men glided back down the corridor to the engine room. The reassembly of the breech mechanism was far from completed, and Grant did not like to interrupt. He was, of course, reasonably familiar with such motors, and knew that their assembly was a delicate task even for an expert.
Cray’s makeshift magnetic device for controlling the relay when the breech was sealed was a comment on the man’s ingenuity. It was not his fault that none of the men noticed that the core of the relay was made of the same alloy as the great screw cocks which held the engine-room doors shut, and the small bolts on the doors in the cargo hold. It was, in fact, a delicate governor, controlling the relation between fuel flow and the breech field strength—a very necessary control, since the field had to be strong enough to keep the hot vapor from actual contact with the breech, but not strong enough to overcome the effect of the fields protecting the throat of the tube, which were at right angles to it. There was, of course, a similar governor in man-made motors, but it was normally located in the throat of the tube and was controlled by the magnetic effect of the ion steam. The device was not obvious, and of course was not of a nature which a human engineer would anticipate. It might have gone on operating normally for an indefinite period, if Cray had used any means whatever, except magnetic manipulation, to open and close the relay.
The engineers finally straightened and stood back from their work. The breech was once more in place, this time without the error in alignment which had caused the discovery of the seal. Clamped to the center of the dome, just where the fuel feed tube merged with its surface, was the control which had been pieced together from articles found in the tool cabinets. It was little more than a coil whose field was supposed to be strong enough to replace that of the interior solenoid through the metal of the breech.
Preble had gone outside, and now returned to report that the slight downward tilt of the end of the ship in which they were working would cause the blast from this particular tube to strike the ground fifty or sixty yards to the rear. This was far enough for safety from splash, and probably close enough so that the intensity of the blast would not be greatly diminished.