The Tactics Of Mistake

by Gordon R. Dickson

  10

  Stars were beginning to fill the Bakhallan sky as Cletus and Melissa reached the gates to the Navy Yard and were met by an ensign attached to Wefer Linet's staff. The ensign conducted them inside to the ramp where the massive, black, two-story-tall shape of a Mark V squatted on its treads just above the golden-tinged waters of the Bakhallan harbor. Cletus had phoned Wefer immediately on parting from Eachan and Melissa to set up the evening's excursion.

  Wefer had been enthusiastic. Navy regulations, he gleefully informed Cletus, absolutely forbade his allowing a civilian such as Melissa aboard a duty Navy vehicle like the Mark V. But, personally, he did not give a damn. For the record, he had caught only the words "Dorsai" and "Khan" when Cletus had phoned him earlier—and to whom, of course, could those words apply but to a mercenary colonel of his acquaintance, who was certainly no civilian? So he would be waiting for Colonel Grahame and Colonel Khan aboard the Mark V at 7 P.M.

  Awaiting them he was. Moreover, he seemed to have shared the joke of his little deception of Navy regulations with his under-officers and crew. The ensign meeting Cletus and Melissa at the Navy Yard gate had gravely addressed Melissa as "Colonel"; and they were hardly aboard the Mark V before three of the seamen, grinning broadly, had found occasion to do the same.

  This small and ridiculous joke, however, turned out to be just the straw needed to break the back of Melissa's stiffness and reserve. On the fourth occasion of being addressed as "Colonel," she laughed out loud—and began from then on to take an honest interest in the outing.

  "Any place in particular you'd like to see?" asked Wefer, as the Mark V put itself into motion and rumbled slowly down its ramp into the bay.

  "Up the river," said Cletus. "Make it so, Ensign."

  "Aye, sir," said the ensign who had met them at the gate. "Balance all tanks fore and aft, there!"

  He was standing at the con, a little to the left of Wefer, Cletus and Melissa, who were placed before the large, curved shape of the hemispherical screen, which looked through the muddy water ahead and about them as though it were clear as glass, to pick up the shapes of ships' undersides and other solid objects below water level in the harbor.

  There was a faint hissing and rumbling noise all around them. The vibration and sound of the heavy treads on the ramp suddenly ceased, and the water line shown on the hemispherical screen moved up above the horizon mark as the huge vehicle balanced out its ballast, replacing water with compressed air where necessary, and vice versa, so that the submarine dozer—its hundreds of tons of land weight now brought into near balance with an equal volume of water—floated as lightly as a leaf in air down to the muddy bottom of the harbor, sixty feet below.

  "All forward, right thirty degrees horizontal," ordered the ensign; and they began their underwater tour upriver from Bakhalla.

  "You'll notice," said Wefer in the fond tone of a father pointing out the talents of his first newborn, "our treads aren't touching the bottom here. There's nearly ten feet of loose silt and muck underneath us before we hit anything solid enough for the Mark V to walk on. Of course, we could settle down into it and do just that, if we wanted to. But why bother? We're as much at home and a lot more mobile to staying up in the water itself and simply swimming with the treads … Now look there … "

  He pointed to the screen, where, some two hundred yards ahead of them, the bottom dipped abruptly below their level of sight for a space of perhaps fifty yards before it rose again.

  "That's the main channel—the main current line to the sea," Wefer said. "We clean that out daily—not because there're any ships here with draft enough to need a hundred and ten feet of water under them, but because that trench provides a channel for the current that helps keep the harbor from silting up. Half of our work's understanding and using existing patterns of water movement. By keeping that channel deep, we cut our normal silt-removal work in half. Not that we need to. It's just the Navy way to do it as efficiently as possible."

  "You mean you've got enough Mark V's and crews to keep the harbor clear even if the channel wasn't there?" Cletus asked.

  Wefer snorted good-humoredly. "Got enough … " he echoed. "You don't know what these Mark V's can do. Why I could keep the harbor clean, even without the current channel, with this one machine alone! … Let me show you around here."

  He took Cletus and Melissa on a tour of the Mark V's interior, from the diver's escape chamber down between the massive treads to the arms turret at the top of the vehicle, which could be uncovered to allow the Mark V to fire either its two heavy energy rifles or the underwater laser with which it was provided.

  "You see why Traynor wanted these Mark V's for use in the jungles," concluded Wefer, as they ended their tour back in the control room before the hemispherical screen. "It hasn't got the fire power of the Army's jungle-breaker tanks, but in every other respect, except land speed, it's so far superior that there's no comparison—"

  "Sir," interrupted the ensign behind him, "deep-draft surface vessel coming down the channel. We're going to have to get down and walk."

  "Right. Make it so, Ensign," answered Wefer. He turned to the screen and pointed at the V-shaped object cutting the line of the river surface some two hundred yards ahead of them. "See that, Cletus? … Melissa? It's a boat drawing nine or ten feet of water. The channel here's less than fifty feet deep and we're going to have to get right down on the bottom to make sure that boat goes over with a good couple of fathoms of clearance."

  He squinted at the V shape growing on the screen. Suddenly, he laughed. "Thought so!" he said. "That's one of your river patrol boats, Cletus. Want to have a look at its topside?"

  "You mean, with a sensor float?" asked Cletus, quietly.

  Wefer's jaw dropped. "How'd you know about that?" he demanded, 'staring.

  "There was an article about it in the Navy-Marine Journal a little less than two years ago," answered Cletus. "It struck me as the sort of device a sensible navy would put aboard a vehicle like this."

  Wefer still stared at him, almost accusingly. "Is that so?" he said.

  "What else about the Mark V do you know that I don't know you know?"

  "I know that with a bit of luck you might be able to capture a boatload of Neulander saboteurs and supplies bound for Bakhalla tonight, if you want to try for it. Have you got a map of the river?"

  "A map?" Wefer lit up. He leaned forward and punched buttons below the hemispherical screen. The image on it vanished, to be replaced by a map showing the main river channel with its tributaries from the harbor mouth at Bakhalla to some thirty miles upstream. A barely moving red dot in the shape of a Mark V seen from above was crawling up the main channel in representation of the vehicle enclosing them. "What guerrillas? Where?"

  "About six kilometers upstream from here," Cletus answered. He reached out to point with his forefinger to a spot ahead of the small, red, moving shape of the Mark V, where a tributary almost as large as the main river joined it at that spot. Up beyond the point of joining, the tributary spread itself out into a number of small streams and then marshland.

  "There's an unusually high tide tonight, as you know," Cletus said. "So from this point on down there will be at least an extra eight feet of water in the main channel. Enough extra depth so that any small upriver motor launch could make it down into Bakhalla harbor towing a good load of supplies, and even personnel, behind it, safely underwater in a drogue pod. It's just a guess on my part, of course, but it hardly seems to me that the guerrillas would let a chance like this slip by without making an effort to get men and supplies to their people in the city."

  Wefer stared at the map and slapped his leg in delight. "You're right!" he exploded. "Ensign, we're headed for that confluence Colonel Grahame just pointed out. Button up for noise, and get the weapons turret uncovered topside."

  "Aye, sir," answered the ensign.

  They reached the juncture point between the tributary point and the mainstream, which Cletus had pointed out. The Mark V crept ou
t of the channel into the relatively shallow water near the river-bank opposite the mouth of the tributary and stopped there, its turrets less than five feet below the river surface. The sensor float was released from the upper hull of the vehicle and popped to the surface—a small, buoyant square of material with the thin metal whisker of a sensor rod rising one meter from it into the air, the two connected by a fine wire to the communications equipment of the Mark V. The sensor rod had to view the scene around it by available light only; but its resolving power was remarkable. The image of the scene it sent down to the hemispherical screen in the command room of the Mark V below was very nearly as clear as if broad daylight, rather than a fingernail paring of a moon, was illuminating the conjunction of the two streams.

  "Not a hull in sight," muttered Wefer, rotating the view in the hemispherical screen to take in the full 180 degrees scanned by the sensor rod. "I suppose we'll just have to sit here and wait for them."

  "You could be taking a few precautions, meanwhile," suggested Cletus.

  Wefer glanced aside at him. "What precautions?"

  "Against their getting away downstream if by some chance they manage to slip by you," said Cletus. "Is there anything to stop you now from moving enough material into the channel downriver so that, if they do come by, they'll run aground just below us?"

  Wefer stared at him in astonishment, which slowly changed to delight. "Of course!" he exploded. "Ensign! Take her downstream!"

  The Mark V moved roughly a hundred yards downstream; and, extending its massive dozer blade crosswise in front of it, began to shovel sand and silt from beneath the water near the river's edges into the main channel. Fifteen minutes work filled the channel for some fifty yards to a level even with the rest of the river bottom. Wefer was inclined to stop at that point, but Cletus suggested he further refine it into a barrier consisting of a wide, sloping ramp rising gradually to within half a dozen feet of the surface. Then, also at Cletus' suggestion, the Mark V returned, not merely upstream, but up into the tributary some fifty yards behind the point where it met with the waters of the main river.

  Here the water was so shallow that the Mark V sat with its turret out in the air. But a few moments work with the dozer blade sufficed to dig a shallow depression so that they could lie in wait completely underwater.

  Then the wait began. It was three hours—nearly midnight—before the sensor rod on its float, invisible against the shadow of the foliage lining the tributary's bank, picked up the image of a motor launch sliding down the main channel of the tributary, its motor turning at a speed barely sufficient to keep the drogue pod, towed behind it, underwater.

  They waited, holding their breaths, until ship and drogue had passed. Then Wefer jumped for the command phone, from which he had, some hours since, displaced the ensign.

  "Wait," said Cletus.

  Wefer hesitated, staring at Cletus. "Wait?" he said. "What for?"

  "You know that launch isn't going to be able to get past the barrier you built downstream," answered Cletus. "So why not sit here a little longer and see if another boat comes along?"

  Wefer hesitated. Then he stepped back from the command phone. "You really think another one might come along?" he asked, thoughtfully.

  "I wouldn't be surprised," said Cletus, cheerfully.

  The answer was hardly out of his mouth before the sensor picked up another approaching motor launch with pod in tow. By the time this was well passed and out into the main river, still another launch had appeared. As Wefer stood staring with incredulous delight into the hemispherical screen, twenty boats towing pods passed within thirty yards of the submerged Mark V.

  When a couple of minutes had gone by following the passage of the twenty boats and pods, Cletus suggested that probably it was time they were checking up on what had happened downstream. Wefer put the Mark V in motion. It surged up out of its shallow hole and plunged under the surface again down into the main channel of the tributary.

  They reached the central channel of the main river, and turned downstream. Their infrared searchlights underwater, as well as the sensor rod being towed on its float above them, gave them a picture of wild confusion just ahead of them. Of the twenty launches that had passed them, fully half were firmly aground in the sloping ramp of river bottom that the Mark V had built. The rest, still afloat but with their drogue pods bobbing helplessly on the surface behind them, were valiantly trying to tow the stranded vessels free. Wefer commanded the Mark V to a halt. He stared into the screen with mingled elation and dismay.

  "Now what?" he muttered to Cletus. "If I charge on down there, the ones that aren't stuck are just going to turn around and beat it upriver and get away. Of course I've got the weapons in the turret. But still, a lot of them are going to get past me."

  "As a suggestion," said Cletus, "how's this Mark V of yours at making a wave?"

  Wefer stared at him. "A wave?" he said—and then repeated, joyously. "A wave!"

  He barked orders into the command phone. The Mark V backed up a hundred yards along the channel of the main river and stopped. The two wings of its dozer blade, which had been folded back against its body to reduce drag while traveling, folded forward again and extended themselves to right and. left until the blades' full area of twenty yards of width and ten feet of height were exposed. Delicately, Wefer tilted the front of the Mark V upward until the top half of the blade poked through the surface of the river and the treads were swimming freely in the water. Then he threw the engines into full speed, forward.

  The Mark V rushed down the river in a roar of water, checked itself and sank itself to the bottom of the channel just fifty yards short of the still-floating launches. For a moment a wall of water hid the scene ahead; and then this passed, speeding like an ever-diminishing ripple farther downstream.

  Left behind was a scene of wreckage and confusion.

  Those launches that had already been aground had had their decks swept by the wave that the Mark V had created. In some cases they had been flipped on their sides by the wave or even turned completely upside down. But the greatest effect was to be seen upon those launches that had still had water under their keels and had been trying to tow the grounded ones loose.

  Without exception these free-floating boats had been driven aground as well. In many cases they had been literally hammered into the soft soil of the piled-up river bed. One launch was standing on its nose, its prow driven half a dozen feet into the sand and silt below.

  "I think they're ready for you now," Cletus said to Wefer.

  If anything more was needed to complete the demoralization of the guerrillas aboard the launches it was the sight of the black shape of the Mark V roaring up into view out of the river depths, the two heavy energy rifles in its turret sweeping ominously back and forth. Almost without exception those who had managed to cling to their battered crafts dove overboard at the sight and began to swim frantically for the banks of the river.

  "Turret—" began Wefer excitedly. But Cletus put his hand over the phone.

  "Let them go," Cletus said. "The important men'll still be sealed inside the pods. Let's see about collecting them before they get too worried by all that's happened and start breaking out."

  The advice was good. The Neulanders inside the pods had reached the limits of their endurance with the tossing about they had taken in the wave generated by the Mark V. Already more than one of the pods bobbing helplessly on the surface of the water, still tethered to their grounded launches, was beginning to split along the top, as those within activated their emergency exits. Wefer wheeled the Mark V into the midst of the wreckage and sent his ensign with three seamen out the Mark V's top hatch with hand weapons to cover the Neulanders as they emerged. They were ordered to swim to the Mark V, where they were searched, put in wrist restraints and herded down the hatch to be locked up in the Mark V's forward hold. Cletus and Melissa stayed discreetly out of sight.

  Its forward hold crammed with prisoners, and the cargo pods filled with suppl
ies in tow, the Mark V returned to its base at the Bakhalla Navy Yard. After disposing of their prisoners and their spoils, Cletus, Melissa and Wefer at last got into the city for that late—now early morning—supper they had planned. It was after four in the morning when Cletus took a tired but happy Melissa back to her father's residence. However, as they approached their destination, Melissa sobered and fell silent; and when they pulled up in front of the door of the house that the Exotics had put at the disposal of Melissa and Eachan, she did not offer to get out of the car right away.

  "You know," she said, turning to Cletus, "you're pretty remarkable, after all. First those guerrillas on our way into Bakhalla, then the ones you captured up at fitter's pass. And now, tonight."

  "Thanks," he said, "but all I did was anticipate the optimum moves for deCastries to make, and arrange to be on the scene when they were made."

  "Why do you keep talking about Dow as if he was having some sort of personal duel with you?"

  "He is," said Cletus.

  "The Outworlds Secretary for the Coalition—against some unknown lieutenant-colonel in an Alliance Expeditionary Force? Does that make sense?"

  "Why not?" Cletus said. "He has a great deal more to lose than an unknown lieutenant-colonel in an Alliance Expeditionary Force."

  "But you're just imagining it all. You have to be!"

  "No," said Cletus. "Remember I pushed him into an error of judgment with the sugar cubes in the dining lounge of the ship? The Outworlds Secretary for the Coalition can't afford to be made a fool of by an unknown Alliance lieutenant-colonel—as you describe me. It's true nobody but you knows—and only because I told you—that he did make a mistake, then—"

  "Was that why you told me what you'd done?" Melissa interrupted quickly. "Just so I'd tell Dow?"

  "Partly," said Cletus. She drew in her breath sharply in the darkness. "But only incidentally. Because it really didn't matter whether you told him or not. He knew I knew. And it simply wasn't good policy to let someone like me walk around thinking that I could beat him, at anything."