when attached to the hull, rather like a long, narrow hairpin with a set of right-angle bends near the center where it had outlined the helicopter lock, the cut ends being some two feet apart. The original vertical component of its curvature, formerly impressed by the shape of the hull, had now flattened out under gravity. The unit had been turned over during the lowering so that the prongs which had attached it to the plastic were now pointing upward; hence there was good contact with the ice for its entire length. The Mesklinites spent a few minutes trying to straighten it out; Benj got the impression that they wanted to run it around the side of the hull as closely as possible. However, it finally dawned on them that the free ends would have to be close together anyway in order to go into the same power box, so they left the wire alone and dragged the power unit aft. One of them examined the holes in the box and the ends of the wire carefully, while the other stood by. Benj could not see the box very well, since its image on the screen was very small, but he was familiar with similar machines. It was a standard piece of equipment which had needed very little modification to render it usable on Dhrawn. There were several kinds of power takeoff on it besides the rotating field used for mechanical drive. The direct electrical current which Borndender wanted could be drawn from any of several places; there were contact plates on opposite sides of the box which could be energized; several different sizes of jack-type bipolar sockets and simple unipolar sockets at opposite ends of the box. The plates would have been easiest to use, but the Mesklinites, as Benj learned later, had dismissed them as too dangerous; they chose to use the end sockets. This meant that one end of the “hairpin” had to go into one end of the unit, and the other into the other end. Borndender already knew that the wire was a little large for these holes and would have to be filed down, and had brought the appropriate tools out with him; this was no problem. Bending the ends, however, so that short lengths of them pointed toward each other, was a different matter. While he was still working on this problem, the rest of the crew emerged from the main lock with their burden of hydroponic tanks, pumps, lights, and power units, and headed northward toward the side of the valley. Borndender ignored them, except for a brief glance, wondering at the same time whether he could commandeer some assistance. The two ninety-degree bends he had to make were not entirely a matter of strength. The metal was of semicircular cross section, about a quarter of an inch in radius; Benj thought of it as heavy wire, while to the Mesklinites it was bar stock. The alloy was reasonably tough even at a hundred and seventy degrees Kelvin, so there was no risk of breaking it. Mesklinite strength was certainly equal to the task. What the two scientists lacked, which made the bending an operation instead of a procedure, was traction. The ice under them was fairly pure water with a modest percentage of ammonia, not so far below its melting point or removed from the ideal ice crystal structure as to have lost its slipperiness. The small area of the Mesklinite extremities caused them to dig in in normal walking, which combined with their low structure and multiplicity of legs, prevented slipping during ordinary walking around the frozen-in Kwembly. Now, however, Borndender and his assistant were trying to apply a strong sidewise force, and their twenty pounds of weight simply did not give enough dig for their claws. The metal refused to bend, and the long bodies lashed about on the ice with Newton’s Third Law in complete control of the situation. The sight was enough to make Benj chuckle in spite of his worry, a reaction which was shared by Seumas McDevitt, who had just come down from the weather lab. Borndender finally solved his engineering problem by going back into the Kwembly and bringing out the drilling equipment. With this he sank half a dozen foot-deep holes in the ice. By standing lengths of drill-tower support rod in these he was able to provide anchorage for the Mesklinite muscles. The rod was finally changed from a hairpin to a caliper shape. Fitting the ends into the appropriate holes was comparatively easy after the filing was finished. It involved a modest lifting job to get the wire up to the two-inch height of the socket holes but this was no problem of strength or traction and was done in half a minute. With some hesitation, visible even to the human watchers, Borndender approached the controls of the power unit. The watchers were at least as tense; Dondragmer was not entirely sure that the operation was safe for his ship, having only the words of the human beings about this particular situation. Benj and McDevitt also had doubts about the efficacy of the jury-rigged heater. Their doubts were speedily settled. The safety devices built into the unit acted properly as far as the machine’s own protection was concerned; they were not, however, capable of analyzing the exterior load in detail. They permitted the unit to deliver a current, not a voltage, up to a limit determined by the manual control setting. Borndender had of course set this at the lowest available value. The resistor lasted for several seconds, and might have held up indefinitely if the ends had not been off the ice. For most of the length of the loop, all went well. A cloud of microscopic ice crystals began to rise the moment the power came on, as water boiled away from around the wire and froze again in the dense, frigid air. It hid the sight of the wire sinking into the surface ice, but no one doubted that this was happening. The last foot or so at each end of the loop, however, was not protected by the high specific and latent heats of water. Those inches of metal showed no sign of the load they were carrying for perhaps three seconds; then they began to glow. The resistance of the wire naturally increased with its temperature, and in the effort to maintain constant current the power box applied more voltage. The additional heat developed was concentrated almost entirely in the already overheated sections. For a long moment a red, and then a white, glow illuminated the rising cloud, causing Dondragmer to retreat involuntarily to the other end of the bridge while Borndender and his companion flattened themselves against the ice. The human watchers cried out, Benj wordlessly, McDevitt protestingly, “It can’t blow!” Their reactions were of course far too late to be meaningful. By the time the picture reached the station, one end of the wire loop had melted through and the unit had shut down automatically. Borndender, rather surprised to find himself alive, supplemented the automatic control with the manual one, and without taking time to report to the captain set about figuring what had happened. This did not take him long; he was an orderly thinker, and had absorbed a great deal more alien knowledge than had the helmsmen, still hoping for rescue a few yards away. He understood the theory and construction of the power units about as well as a high school student understands the theory and construction of a television set; he could not have built one himself, but he could make a reasonable deduction as to the cause of a gross malfunction. He was more of a chemist than a physicist, as far as specific training went. While the human beings watched in surprise and Dondragmer in some uneasiness, the two scientists repeated the bending operation until what was left of the resistor was once again usable. With the drilling equipment they made a pit large enough to hold the power box at the end of the deep groove boiled in the ice by the first few seconds of power. They set the box in the hole, connected the ends once more, and covered everything with chips of ice removed in the digging, leaving only the controls exposed. Then Borndender switched on the power again, this time retreating much more hastily than before. The white cloud reappeared at once, but this time grew and spread. It enveloped the near side of the Kwembly, including the bridge, blocking the view for Dondragmer and the communicator lens. Illuminated by the outside flood lamps, it caught the attention of the crew, now nearing the edge of the valley, and of Stakendee and his men miles to the west. This time the entire length of the wire was submerged in melted ice, which bubbled away from around it as hot vapor, condensed to liquid a fraction of a millimeter away, evaporated again much less violently from the surface of the widening pool, and again condensed, this time to ice, in the air above. The steaming pool, some three quarters of the Kwembly ’s length and originally some six feet in width, began to sink below the surrounding ice, its contents borne away as ice dust by the gentle wind faster than they were replenished by melting. One side of it reached the cruiser, and Dondragmer, catching a glimpse of it through a momentary break in the swirling fog, suddenly had a frightening thought. He donned his air suit hurriedly and rushed to the inner door of the main lock. Here he hesitated; with the suit’s protection he could not tell by feel whether the ship was heating dangerously, and there were no internal thermometers except in the lab. For a moment he thought of getting one; then he decided that the time needed might be risky, and opened the upper safety valves in the outer lock, which were handled by pull-cords from inside reaching down through the liquid trap. He did not know whether the heat from outside would last long enough to boil ammonia in the lock itself — the Kwemhly ’s hull was well insulated, and leakage would be slow, but he had no desire to have boiling ammonia confined aboard his command. It was an example of a little knowledge causing superfluous worry; the temperature needed to bring ammonia’s vapor pressure anywhere near the ambient values would have made an explosion the least of any Mesklinite’s concerns. However, no real harm was done by opening the valves, and the captain felt better as a result of the action. He returned hastily to the bridge to see what was going on. A gentle breeze from the west was providing occasional glimpses as it swept the ice fog aside and he could see that the level of the molten pool was lower. Its area had increased greatly, but as the minutes passed he decided that some limit had been reached. His two men were visible at times, crawling here and there trying to find a good viewpoint. They finally settled down almost under the bridge, with the breeze behind them. For some time the liquid level seemed to reach a steady state, though none of the watchers could understand why. Later they decided that the spreading pool had melted its way into the still-liquid reservoir under the Kwembly, which took fully fifteen minutes to evaporate. By the end of that time,
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