The North Tower had been a ruin for a century, a jagged tooth of granite overlooking the valley. To the ancestors of Oakhaven, it was a monument to a forgotten siege. To Alaric, it was a vertical kiln waiting to happen.
"Higher," Alaric commanded, pointing to the foundation of the tower. "We need a chimney effect. The taller the stack, the stronger the natural draft."
Old Tom and a dozen bewildered masons were stacking the salvaged stone into a tapering, cylindrical furnace. Alaric wasn't building a standard bloomery, the tiny, inefficient pits medieval smiths used to produce spongy "blooms" of iron that had to be hammered for days to remove impurities. He was building a Blast Furnace.
"My lord, the walls will melt," the head mason argued, wiping grit from his eyes. "No stone can hold the heat you're talking about."
"Not ordinary stone," Alaric countered. He pointed to a pile of yellowish clay he'd had the children gather from the riverbank. "We line the inside with firebrick, clay mixed with crushed quartz and bone ash. It will vitrify. It will create a ceramic skin that laughs at the fire."
As the sun dipped behind the mountains, the furnace was ready. It stood ten feet tall, a monstrous chimney of stone and clay. At its base, two massive bellows, powered by a makeshift waterwheel Alaric had rigged to the castle's diverted well-stream, waited to breathe life into the beast.
---
Late that night, Alaric sat by a small campfire near the furnace, his modern mind running through the carbon-to-iron ratios. He was so deep in thought he almost didn't hear the muffled clink of metal on stone.
He stood silently, moving into the shadows of the North Tower.
Near the base of the furnace, a dark figure was crouched, prying at the fresh firebrick lining with a heavy crowbar. If the lining was breached before the first firing, the molten iron would eat through the outer stone, causing a catastrophic structural failure, and likely killing whoever was standing nearby.
"The Duke pays well for a ruined tower, doesn't he?" Alaric's voice was like ice.
The figure bolted. Alaric didn't chase, he wasn't a warrior. Instead, he whistled, a sharp, piercing sound.
From the darkness above, Kaelen dropped like a hawk. He had been perched on the tower's remains, acting as the "security detail" Alaric had insisted upon. With a single fluid motion, Kaelen tackled the saboteur, pinning him to the muddy earth.
Kaelen ripped the hood back. It wasn't the Bailiff. It was the Captain of the Guard's youngest nephew, a boy no older than Alaric.
"Who told you to do this?" Kaelen growled, his dagger humming as it cleared its sheath.
"I... I didn't mean... the black hawk..." the boy stammered, his eyes bulging with terror. "They said the Young Lord was a sorcerer! That he was building a gate to the Silent Halls!"
Alaric stepped into the light. He didn't look angry, he looked disappointed. "Superstition is the greatest enemy of progress, Kaelen. The Duke isn't just fighting us with gold, he's fighting us with fear."
Alaric knelt beside the boy. "Go back to your uncle. Tell him the 'gate' opens tomorrow. And tell him that if he wants to see what's on the other side, he should bring his sword. He'll need it to see the steel I'm about to forge."
---
The next morning, the furnace was packed. Layers of charcoal, iron ore gathered from the bog, and crushed limestone (acting as a flux to carry away impurities) were piled to the top.
"Fire it," Alaric ordered.
The bellows began their rhythmic groan. The waterwheel turned, forced by the diverted stream. Within an hour, the North Tower wasn't just a ruin, it was a volcano. A low, terrifying roar vibrated through the ground. The air around the furnace shimmered with a heat so intense the villagers backed away in primal fear.
"Now!" Alaric shouted over the roar.
Old Tom stepped forward with a long iron rod and pierced the clay plug at the base.
For a second, there was silence. Then, a river of white-gold liquid light burst forth. It flowed into the sand molds Alaric had prepared, not in the shape of swords, but in the shape of Pigs.
"Liquid iron," Tom whispered, his face illuminated by the glow. "It flows like water. I've never seen... it shouldn't be possible."
"It's Cast Iron, Tom," Alaric said, his eyes reflected in the molten metal. "It's brittle now, but once we stir it in the puddling furnace and burn off the excess carbon, we won't have iron anymore. We'll have Steel."
Alaric looked toward the horizon, toward the Duchy of Blackhawk. He had the food. He had the fuel. Now, he had the metal.
"Kaelen," Alaric said, turning to his brother. "Start picking the strongest men from the village. Not the ones who can swing a sword, the ones who can follow an order. We're going to build a new kind of army."