The third day was the hardest.
My hands were a map of blisters, and my back felt as though someone had driven a hot iron rod down my spine. The "old" Julian's body was screaming for the wine it was used to, but I drowned the tremors in caffeine-heavy infusions of wild herbs Pip had found for me.
"Steady," I muttered, my voice raspy as I adjusted the clay seal on the retort's venting pipe. "If air leaks in now, the whole batch oxidizes. We'll be back to square one."
Gunnar stood behind me, his massive arms crossed. He had spent the last forty-eight hours working harder than any three men combined, driven by a mix of fear and a burgeoning, reluctant curiosity.
"The fire's been burning for twelve hours, My Lord," Gunnar said, nodding toward the central firebox. "The stone is glowing. I've never seen wood smoke turn blue like that. It looks... wrong."
"It's not smoke, Gunnar. It's wood gas," I said, wiping soot from my forehead. "The impurities are being cooked out of the Iron-Bark and fed back into the flame. It's a self-consuming cycle. In a few minutes, the pressure will drop. That's when we kill the heat."
The workers had gathered in a semi-circle, keeping a respectful distance. To them, the kiln was a strange, breathing beast. It didn't roar like their open pits; it hissed.
"Now," I commanded. "Seal the intake. Smother the firebox."
Gunnar barked orders. The men leaped forward, shoveling wet clay and sand into the air intakes, choking the life out of the fire. The hissing slowly died down to a low, metallic hum.
"We wait," I said, sitting down on a crate. My legs were shaking. "If we open it too early, the hot carbon will ignite the moment it touches oxygen. We wait for the temperature to equalize."
Four hours later, under the light of a rising moon, we broke the clay seal.
Gunnar used a long iron pry-bar to crack the lid of the internal vessel. A faint wisp of steam escaped, but no smoke. No ash.
He reached in with a pair of tongs and pulled out a single branch of Iron-Bark.
It looked identical in shape to the wood we had put in, but the color was a deep, iridescent black that seemed to swallow the torchlight. Gunnar tapped it against the stone foundation.
Clink.
It didn't thud. It sounded like a piece of fine crystal hitting a marble floor.
"By the gods," one of the older burners whispered, stepping forward. He took the piece of charcoal, his rough fingers trembling. "It's... it's solid. No cracks. No soft spots."
"Snap it," I ordered.
The man snapped the branch. The interior was a uniform, glass-like obsidian. There was no brown wood left in the center—the hallmark of a failed, uneven burn.
"This," I said, standing up and ignoring the dizzy spell that hit me, "is the highest-grade fuel in this kingdom. It will burn hotter than coal and cleaner than oil. But we aren't selling it. Not yet."
I looked at Marlo, who had returned from the castle with a cart full of copper pipes and lead fittings from the old brewery.
"Load the charcoal into the cart," I commanded. "Gunnar, take ten men. We're moving to the Salty Flats. We have ten days of production left before the Count's interest matures, and I intend to spend them making the South look like amateurs."
The Salty Flats were a depressing sight.
A series of shallow, cracked clay basins stretched out toward the eastern horizon, filled with a stagnant, greyish brine. The air here tasted of minerals and rot.
The foreman of the salt works was a man named Hobb. He was thin, bitter, and possessed the permanent scowl of someone who had spent thirty years failing to make a profit.
"You want to do what?" Hobb asked, squinting at the copper pipes Marlo was unloading. "Filter the brine through... burnt wood? Master Julian, I've been making salt since your father was a squire. You boil the water, you get the salt. That's the law of the earth."
"The 'law of the earth' has been giving you bitter, grey sludge, Hobb," I said, already measuring the distance between the primary brine spring and the new filtration site. "Your salt is full of magnesium. It's why it clumps. It's why it tastes like metal. We're going to strip it out."
I didn't wait for his permission. I began directing the men to build a "Filter Tower."
It was a vertical stack. At the top, a vat of raw brine. Below it, layers of fine river sand, crushed limestone, and—most importantly—a three-foot thick bed of our new, crushed Iron-Bark charcoal.
"The charcoal acts as a molecular sieve," I explained to no one in particular as I tightened a lead valve. "The magnesium ions will cling to the carbon surface, while the pure sodium chloride solution passes through."
Hobb watched us work for two days, his skepticism turning into a brooding silence. By the morning of the fifth day, the first "Purified Brine" began to drip from the bottom of the copper pipe into a clean iron kettle.
The liquid was crystal clear. It looked like spring water.
"It's just water," Hobb scoffed. "You've filtered the salt right out of it, you clever fool."
"Taste it," I said.
Hobb dipped a finger into the kettle and touched it to his tongue. His eyes went wide. He dipped it again, deeper this time.
"It... it doesn't sting," he whispered. "It's salt. But it's... sweet. No, not sweet. Just... clean."
"Boil it," I said, a cold grin spreading across my face. "Slowly. Don't let the flame touch the bottom of the pan. We want large crystals, Hobb. I want flakes as thin as a moth's wing."
We spent the night huddled around the evaporation pans. As the water hissed away, something began to form on the surface of the brine.
It wasn't the clumpy, grey mud they were used to.
Under the morning sun, the pans were filled with brilliant, translucent white diamonds. They caught the light, refracting it into tiny rainbows. It was so white it looked like a fallen cloud.
Hobb reached in, picking up a large, flat flake. He held it up to the sun. You could see through it.
"Snow Salt," Marlo breathed, falling to his knees beside the pan. "It's Snow Salt. From the middle of the Blackwood."
"No, Marlo," I said, picking up a handful of the pristine crystals and letting them pour through my fingers. "Snow Salt is full of ocean impurities. This is better. This is Pure Grade."
I looked at Gunnar and Hobb. For the first time, they weren't looking at me like a drunkard. They were looking at me with a terrifying kind of awe.
"We have twenty days left," I said. "I want every pan in this Barony scrubbed. I want the kilns running twenty-four hours a day. We aren't just paying a tax, gentlemen. We're going to start a trade war."