The Mammoth Book of Golden Age SF

by Martin Greenberg

  Now she moved, though, and quickly. With that incredibly fast shifting, she leaped backwards and pivoted out of range before Tom could check the shovel’s mad swing. The heavy swing-friction blocks smoked acridly as the machine slowed, stopped and swung back. Tom checked her as he was facing the Seven, hoisted his bucket a few feet, and rehauled, bringing it about halfway back, ready for anything. The four great dipper-teeth gleamed in the sun. Tom ran a practised eye over cables, boom and dipper-stick, liking the black polish of crater compound on the sliding parts, the easy tension of well-greased cables and links. The huge machine stood strong, ready and profoundly subservient for all its brute power.

  Tom looked searchingly at the Seven’s ruined engine hood. The gaping end of the broken air-intake pipe stared back at him. “Aha!” he said. “A few cupfuls of nice dry marl down there’ll give you something to chew on.”

  Keeping a wary eye on the tractor, he swung into the bank, dropped his bucket and plunged it into the marl. He crowded in deep, and the Murphy yelled for help but kept on pushing. At the peak of the load a terrific jar rocked him in the saddle. He looked back over his shoulder through the door and saw the Seven backing off again. She had run up and delivered a terrific punch to the counter-weight at the back of the cab. Tom grinned tightly. She’d have to do better than that. There was nothing back there but eight or ten tons of solid steel. And he didn’t much care at the moment whether or not she scratched his paint.

  He swung back again, white marl running away on both sides of the heaped bucket. The shovel rode perfectly now, for a shovel is counterweighted to balance true when standing level with the bucket loaded. The hoist, swing frictions and the brake linings had heated and dried themselves of the night’s condensation moisture, and she answered the controls in a way that delighted the operator in him. He handled the swing lever lightly, back to swing to the right, forward to swing to the left, following the slow dance the Seven had started to do, stepping warily back and forth like a fighter looking for an opening. Tom kept the bucket between himself and the tractor, knowing that she could not hurt a tool that was built to smash hard rock for twenty hours a day and like it.

  Daisy Etta bellowed and rushed in. Tom snapped the hoist lever back hard, and the bucket rose, letting the tractor run underneath. Tom punched the bucket trip, and the great steel jaw opened, cascading marl down on the broken hood. The tractor’s fan blew it back in a huge billowing cloud. The instant that it took Tom to check and dump was enough, however, for the tractor to dance back out of the way, for when he tried to drop it on the machine to smash the coiled injector tubes on top of the engine block, she was gone.

  The dust cleared away, and the tractor moved in again, feinted to the left, then swung her blade at the bucket, which was just clear of the ground. Tom swung to meet her, her feint having got her in a little closer than he liked, and bucket met blade with a shower of sparks and a clank that could be heard for half a mile. She had come in with her blade high, and Tom let out a wordless shout as he saw that the A-frame brace behind the blade had caught between two of his dipper-teeth. He snatched at his hoist lever and the bucket came up, lifting with it the whole front end of the bulldozer.

  Daisy Etta plunged up and down and her tracks dug violently into the earth as she raised and lowered her blade, trying to shake herself free. Tom rehauled, trying to bring the tractor in closer, for the boom was set too low to attempt to lift such a dead weight. As it was, the shovel’s off track was trying its best to get off the ground. But the crowd and rehaul frictions could not handle her alone; they began to heat and slip.

  Tom hoisted a little; the shovel’s off track came up a foot off the ground. Tom cursed and let the bucket drop, and in an instant the dozer was free and running clear. Tom swung wildly at her, missed. The dozer came in on a long curve; Tom swung to meet her again, took a vicious swipe at her which she took on her blade. But this time she did not withdraw after being hit, but bored right in, carrying the bucket before her. Before Tom realized what she was doing, his bucket was around in front of the tracks and between them, on the ground. It was as swift and skilful a manoeuvre as could be imagined, and it left the shovel without the ability to swing as long as Daisy Etta could hold the bucket trapped between the tracks.

  Tom crowded furiously, but that succeeded only in lifting the boom higher in the air, since there is nothing to hold a boom down but its own weight. Hoisting did nothing but make his frictions smoke and rev the engine down dangerously close to the stalling point.

  Tom swore again and reached down to the cluster of small levers at his left. These were the gears. On this type of shovel, the swing lever controls everything except crowd and hoist. With the swing lever, the operator, having selected his gear, controls the travel – that is, power to the tracks – in forward and reverse; booming up and booming down; and swinging. The machine can do only one of these things at a time. If he is in travel gear, she cannot swing. If she is in swing gear, she cannot boom up or down. Not once in years of operating would this inability bother an operator; now, however, nothing was normal.

  Tom pushed the swing gear control down and pulled up on the travel. The clutches involved were jaw clutches, not frictions, so that he had to throttle down on an idle before he could make the castellations mesh. As the Murphy revved down, Daisy Etta took it as a signal that something could be done about it, and she shoved furiously into the bucket. But Tom had all controls in neutral and all she succeeded in doing was to dig herself in, her sharp new cleats spinning deep into the dirt.

  Tom set his throttle up again and shoved the swing lever forward. There was a vast crackling of drive chains; and the big tracks started to turn.

  Daisy Etta had sharp cleats; her pads were twenty inches wide and her tracks were fourteen feet long, and there were fourteen tons of steel on them. The shovel’s big flat pads were three feet wide and twenty feet long, and forty-seven tons aboard. There was simply no comparison. The Murphy bellowed the fact that the work was hard, but gave no indications of stalling. Daisy Etta performed the incredible feat of shifting into a forward gear while she was moving backwards, but it did her no good. Round and round her tracks went, trying to drive her forward, gouging deep; and slowly and surely she was forced backward towards the cut wall by the shovel.

  Tom heard a sound that was not a part of a straining machine; he looked out and saw Kelly up on top of the cut, smoking, swinging his feet over the edge, making punching motions with his hands as if he had a ringside seat at a big fight – which he certainly had.

  Tom now offered the dozer little choice. If she did not turn aside before him, she would be borne back against the bank and her fuel tank crushed. There was every possibility that, having her pinned there, Tom would have time to raise his bucket over her and smash her to pieces. And if she turned before she was forced against the bank, she would have to free Tom’s bucket. This she had to do.

  The Murphy gave him warning, but not enough. It crooned as the load came off, and Tom knew then that the dozer was shifting into a reverse gear. He whipped the hoist lever back and the bucket rose as the dozer backed away from him. He crowded it out and let it come smashing down – and missed. For the tractor danced aside – and while he was in travel gear he could not swing to follow it. Daisy Etta charged then, put one track on the bank and went over almost on her beam-ends, throwing one end of her blade high in the air. So totally unexpected was it that Tom was quite unprepared. The tractor flung itself on the bucket, and the cutting edge of the blade dropped between the dipper teeth. This time there was the whole weight of the tractor to hold it there. There would be no way for her to free herself – but at the same time she had trapped the bucket so far out from the center pin of the shovel that Tom couldn’t hoist without overbalancing and turning the monster over.

  Daisy Etta ground away in reverse, dragging the bucket out until it was checked by the bumper-blocks. Then she began to crab sideways, up against the bank, and when Tom tried tentatively to rehau
l, she shifted and came right with him, burying one whole end of her blade deep into the bank.

  Stalemate. She had hung herself up on the bucket, and she had immobilized it. Tom tried to rehaul, but the tractor’s anchorage in the bank was too solid. He tried to swing, to hoist. All the overworked frictions could possibly give out was smoke. Tom grunted and throttled to an idle, leaned out of the window. Daisy Etta was idling too, loudly without her muffler, the stackless exhaust giving out an ugly flat sound. But after the roar of the two great motors the partial silence was deafening.

  Kelly called down, “Double knockout, hey?”

  “Looks like it. What say we see if we can’t get close enough to her to quiet her down some?”

  Kelly shrugged. “I dunno. If she’s really stopped herself, it’s the first time. I respect that rig, Tom. She wouldn’t have got herself into that spot if she didn’t have an ace up her sleeve.”

  “Look at her, man! Suppose she was a civilized bulldozer and you had to get her out of there. She can’t raise her blade high enough to free it from those dipper-teeth, y’know. Think you’d be able to do it?”

  “It might take several seconds,” Kelly drawled. “She’s sure high and dry.”

  “O.K., let’s spike her guns.”

  “Like what?”

  “Like taking a bar and prying out her tubing.” He referred to the coiled brass tubing that carried the fuel, under pressure, from the pump to the injectors. There were many feet of it, running from the pump reservoir, stacked in expansion coils over the cylinder head.

  As he spoke Daisy Etta’s idle burst into that maniac revving up and down characteristic of her.

  “What do you know!” Tom called above the racket. “Eavesdropping!”

  Kelly slid down the cut, stood up on the track of the shovel and poked his head in the window. “Well, you want to get a bar and try?”

  “Let’s go!”

  Tom went to the toolbox and pulled out the pinch bar that Kelly used to replace cables on his machine, and swung to the ground. They approached the tractor warily. She revved up as they came near, began to shudder. The front end rose and dropped and the tracks began to turn as she tried to twist out of the vice her blade had dropped into.

  “Take it easy, sister,” said Tom. “You’ll just bury yourself. Sit still and take it, now, like a good girl. You got it comin’.”

  “Be careful,” said Kelly. Tom hefted the bar and laid a hand on the fender.

  The tractor literally shivered, and from the rubber hose connection at the top of the radiator, a blinding stream of hot water shot out. It fanned and caught both full in the face. They staggered back, cursing.

  “You O.K., Tom?” Kelly gasped a moment later. He had got most of it across the mouth and cheek. Tom was on his knees, his shirt tail out, blotting at his face.

  “My eyes . . . oh, my eyes—”

  “Let’s see!” Kelly dropped down beside him and took him by the wrists, gently removing Tom’s hands from his face. He whistled. “Come on,” he gritted. He helped Tom up and led him away a few feet. “Stay here,” he said hoarsely. He turned, walked back towards the dozer, picking up the pinch bar. “You dirty – !” he yelled, and flung it like a javelin at the tube coils. It was a little high. It struck the ruined hood, made a deep dent in the metal. The dent promptly inverted with a loud thung-g-g! and flung the bar back at him. He ducked; it whistled over his head and caught Tom in the calves of his legs. He went down like a poled ox, but staggered to his feet again.

  “Come on!” Kelly snarled, and taking Tom’s arm, hustled him around the turn of the cut. “Sit down! I’ll be right back.”

  “Where you going? Kelly – be careful!”

  “Careful and how!”

  Kelly’s long legs ate up the distance back to the shovel. He swung into the cab, reached back over the motor and set up the master throttle all the way. Stepping up behind the saddle, he opened the running throttle and the Murphy howled. Then he hauled back on the hoist lever until it knuckled in, turned and leaped off the machine in one supple motion.

  The hoist drum turned and took up slack; the cable straightened as it took the strain. The bucket stirred under the dead weight of the bulldozer that rested on it; and slowly, then, the great flat tracks began to lift their rear ends off the ground. The great obedient mass of machinery teetered forward on the tips of her tracks, the Murphy revved down and under the incredible load, but it kept the strain. A strand of the two-part hoist cable broke and whipped around, singing; and then she was balanced – over-balanced—

  And the shovel had hauled herself right over and had fallen with an earth-shaken crash. The boom, eight tons of solid steel, clanged down on to the blade of the bulldozer, and lay there, crushing it down tightly on to the imprisoning row of dipper-teeth.

  Daisy Etta sat there, not trying to move now, racing her motor impotently. Kelly strutted past her, thumbing his nose, and went back to Tom.

  “Kelly! I thought you were never coming back! What happened?”

  “Shovel pulled herself over on her nose.”

  “Good boy! Fall on the tractor?”

  “Nup. But the boom’s laying across the top of her blade. Caught like a rat in a trap.”

  “Better watch out the rat don’t chew its leg off to get out,” said Tom, drily. “Still runnin’, is she?”

  “Yep. But we’ll fix that in a hurry.”

  “Sure. Sure. How?”

  “How? I dunno. Dynamite, maybe. How’s the optics?”

  Tom opened one a trifle and grunted. “Rough. I can see a little, though. My eyelids are parboiled, mostly. Dynamite, you say? Well, let’s think first. Think.”

  Tom sat back against the bank and stretched out his legs. “I tell you, Kelly, I been too blessed busy these last few hours to think much, but there’s one thing that keeps comin’ back to me – somethin’ I was mullin’ over long before the rest of you guys knew anything was up at all, except Rivera had got hurt in some way I wouldn’t tell you all about. But I don’t reckon you’ll call me crazy if I open my mouth now and let it all run out?”

  “From now on,” Kelly said fervently, “nobody’s crazy. After this I’ll believe anything.” He sat down.

  “O.K. Well, about the tractor. What do you suppose has got into her?”

  “Search me. I dunno.”

  “No – don’t say that. I just got an idea we can’t stop at ‘I dunno.’ We got to figure all the angles on this thing before we know just what to do about it. Let’s just get this thing lined up. When did it start? On the mesa. How? Rivera was opening an old building with the Seven. This thing came out of there. Now here’s what I’m getting at. We can dope these things out about it: It’s intelligent. It can only get into a machine and not into a man. It—”

  “What about that? How do you know it can’t?”

  “Because it had the chance to and didn’t. I was standing right by the opening when it kited out. Rivera was up on the machine at the time. It didn’t directly harm either of us. It got into the tractor, and the tractor did. By the same token, it can’t hurt a man when it’s out of a machine, but that’s all it wants to do when it’s in one. O.K.?

  “To get on: once it’s in one machine it can’t get out again. We know that because it had plenty of chances and didn’t take them. That scuffle with the dipper-stick, f’r instance. My face woulda been plenty red if it had taken over the shovel – and you can bet it would have if it could.”

  “I got you so far. But what are we going to do about it?”

  “That’s the thing. You see, I don’t think it’s enough to wreck the tractor. We might burn it, blast it, and still not hurt whatever it was that got into it up on the mesa.”

  “That makes sense. But I don’t see what else we can do than just break up the dozer. We haven’t got a line on actually what the thing is.”

  “I think we have. Remember I asked you all those screwy questions about the arc that killed Peebles. Well, when that happened, I recollec
ted a flock of other things. One – when it got out of that hole up there, I smelled that smell that you notice when you’re welding; sometimes when lightning strikes real close.”

  “Ozone,” said Kelly.

  “Yeah – ozone. Then, it likes metal, not flesh. But most of all, there was that arc. Now, that was absolutely screwy. You know as well as I do – better – that an arc generator simply don’t have the push to do a thing like that. It can’t kill a man, and it can’t throw an arc no fifty feet. But it did. An’ that’s why I asked you if there could be something – a field, or some such – that could suck current out of a generator, all at once, faster than it could flow. Because this thing’s electrical; it fits all around.”

  “Electronic,” said Kelly doubtfully, thoughtfully.

  “I wouldn’t know. Now then. When Peebles was killed, a funny thing happened. Remember what Chub said? The Seven moved back – straight back, about thirty feet, until it bumped into a roadroller that was standing behind it. It did that with no fuel in the starting engine – without even using the starting engine, for that matter – and with the compression valves locked open!

  “Kelly, that thing in the dozer can’t do much, when you come right down to it. It couldn’t fix itself up after that joyride on the mesa. It can’t make the machine do too much more than the machine can do ordinarily. What it actually can do, seems to me, is to make a spring push instead of pull, like the control levers, and make a fitting slip when it’s supposed to hold, like the ratchet on the throttle lever. It can turn a shaft, like the way it cranks its own starting motor. But if it was so all-fired highpowered, it wouldn’t have to use the starting motor! The absolute biggest job it’s done so far, seems to me, was when it walked back from that welding machine when Peebles got his. Now, why did it do that just then?”

  “Reckon it didn’t like the brimstone smell, like it says in the Good Book,” said Kelly sourly.

  “That’s pretty close, seems to me. Look, Kelly – this thing feels things. I mean, it can get sore. If it couldn’t it never woulda kept driving in at the shovel like that. It can think. But if it can do all those things, then it can be scared!?”