S. Stirling - Dies The Fire

"Now, when this pin has been pulled free, Mr. Trebuchet is no longer our friend. Understand?" Ken Larsson said.

He ignored an impulse to beat his hands together against the chill of the mountain valley and the cold wind that blew down from the heights. That really wasn't very productive when one hand was off at the wrist, and you had a leather sheath tipped with a hand-sized steel hook strapped over the forearm. It still hurt a little too, even a quarter-year after Iron Rod's sword hacked through, and he could still wake up remembering the ugly grinding sensation of steel cracking through bones. Rothman and Pam had done a good job with it.

She never said it didn't make any difference to her; just showed it by the way she acted, he thought, with a brief stab of amazed pleasure even now. Christ, I'm lucky.

Aloud he went on genially: "Mr. Trebuchet is ready to go and anything you get in the way of the parts-like your hand, for instance-is going to go with it."

He waggled the steel hook at them and grinned. The squad of young Bearkillers and ranchers' kids nodded back at him eagerly, looking up at the great machine. None of them seemed to notice the late-afternoon chill or overcast that made his bones ache a little, and the stump where his left wrist used to be ache a lot. Their enthusiasm did make him feel better: and the trebuchet was something to be proud of, as well.

It was basically an application of the lever principle; a long beam between two tall A-frames, pivoted about a third of the way down its length. Swinging from the end of the shorter arm was a huge basket of welded steel rods full of rocks; fastened to the other end was a sling of chains and flexible metal mesh. You hauled down that, fastened it to the release mechanism, and loaded a rock or whatever else you wanted to throw into the sling-dead horses or plague victims pitched over a city wall had been a medieval favorite.

Then you hit the trigger, and the huge weight of the basket full of rocks swung that end of the lever down, hard.

The longer section on the other side of the pivot went up, and turned that force into speed, with the sling adding more leverage. Your projectile went hurtling downrange, as far and fast as anything before cannon. Or after cannon stopped working. It was that simple.

Simple. Simple until you get down to the details, Larsson thought.

He was quite proud of his version. The basic idea was seven centuries old; like so much else, it originally came from China. But he'd thought of improvements-from the base resting on wheel bogies from heavy trucks, to the geared winches that hauled the weight up, to the neat grapnel mechanism that gripped the lever. The medieval models had been built by rule of thumb; precise calculation of mechanical advantage and stronger, lighter materials made this one considerably more efficient.

And now it was ready:

"Stand back, kiddies," Larsson said, remembering Fourth of July celebrations past. Fireworks didn't work, not anymore, but:

"Daddy's going to give the Protector a boot in the ass!"

They cheered, but obeyed. Larsson squinted at the outline of the Protector's Echo Creek castle-at least the sky was cloudy, so he wasn't looking into the sun-ran his hook through the loop at the end of the lanyard cord, and gave a sharp tug.

Chang- whack!

The claws holding the beam snapped back. Cable un-spooled with a rumbling whirr. The great basket of rock seemed to drop slowly at first, then faster and faster, and the steel beam of the throwing arm whirred upward so swiftly that inertia bent it like a bow.

Sss-crack!

At the very top of its arc the chain-and-mesh sling swung upward as well. Another hook was cunningly shaped to let the upper chain of the sling go free at precisely the right moment, and the big boulder flew westward-tumbling as it went, slowing as it reached the height of its arc and then dropping down towards the fort like an anvil from orbit. Dust puffed up around the trebuchet, from under its wheels and the four screw jacks that stabilized it for firing.

"Hit!" shouted a Bearkiller trooper, looking through a pair of heavy tripod-mounted binoculars they'd reclaimed from a tourist lookout point. "Hit!"

Larsson had his own monocular out and put to his good eye-the castle was about half a mile away, and he wanted to know just how his baby functioned. He could see where the quarter-ton rock had struck; in the middle of the earth wall of the fort, halfway between ditch and the palisade. A cloud of dirt drifted away, and he saw the boulder three-quarters buried in the heaped soil.

Well, so far we're just helping build the castle wall, Lars-son thought. No damage except to the barbed wire. But next time:

"Incoming!" the woman at the binoculars shouted. Then: "Short!"

Larsson looked, tensed to dive for the slit trench. A rock rose over the gate of the castle, arching up-in a reverse of his own shot, it seemed to get faster and faster as it approached.

Thud.

It landed in the roadway, cracking and cratering the asphalt, then rolling along until it came to a halt about a hundred yards in front of his own trebuchet. More than enough to hammer anything trying to sneak by the castle on either side, but less range than his, with a lighter load. Probably mounted on some sort of turntable.

"You shouldn't have thought you'd be the only one to come up with this idea, Professor," Larsson said with an evil chuckle. To the crew: "All right, winch her down!"

The crew sprang to work, pumping at the cranks on either side of the frame's rear. There was a quick ratcheting clatter as they took up the slack on the two woven-wire cables that ran up to the peak of the throwing arm and out through block-and-tackle at the middle of the rear brace. That slowed as the weight came on the cables and they had to work at it, but the gearing made the effort steady rather than hard. At last the arm was down, and Larsson threw the lever that brought the jaws of the clamp home on it and slipped home the safety pin-a steel rod the thickness of his thumb and as long as his forearm.

"We need something a little lighter, if we want to hit the palisade or the interior," he said, looking down the row of boulders. Each had its weight chalked on the surface, along with a serial number.

"Number thirty-two!"

The loading crew had two-man pincers for carrying stones, with turned-in sections at the tips, and stout horizontal wooden handles like spades. Four men went after boulder thirty-two, each pair clamping their pincers on it and walking it over to the sling. Larsson carefully raised the chain and loop and dropped them over the hook, removed the pin:

"Incoming!"

This time the yell was much louder, and the sound from the castle was different, a long vibrating tunnngg! from the motte tower.

"Cover!" Larsson said, and jumped into a slit trench; Havel had smiled that crooked smile when he told them those should go in first.

I'm not doing bad for an old man, he thought, puffing and keeping his head down. So I may not be good at waving swords:

Something went over his head with a loud whhht. A fractional second later there was a sharp crack from behind him. He turned and raised his head. There was a row of mantlets about ten yards behind the rock-thrower-heavy shields on bicycle wheels, for archers and crossbowmen to push towards hostile walls. One had been hit.

Not just hit, he thought, whistling softly to himself.

The missile was a four-foot, spear-sized arrow with plastic vanes and a pile-shaped head. It had punched right through the metal facing and double thickness of plywood, and buried itself in the rib cage of a rancher's man who'd been leading a horse behind. The man went down, screaming like a rabbit in a trap and flailing with his arms, but the legs stayed immobile. More people scattered eastward, running from the sudden danger; a few ran three or four steps, then turned and dashed back to drag the injured man to safety. He screamed even louder at that, and was undoubtedly going to die anyway-a pre-Change trauma unit probably couldn't have saved him, but: