Gas and Quicklime

Thjora

One hundred and fifty-two degrees.

That is the temperature where malt starch surrenders to sugar.

Two degrees lower, the enzymes sleep. Two degrees higher, they cook to death, leaving nothing behind but cloudy, useless starch. Ninety-four men in the lower wards will rip their iron bedframes out of the stone by midnight if I miss that number.

I jam the copper probe deep into the steaming mash.

The needle trembles on the brass gauge. One hundred and fifty-one point eight.

"Good girl," I whisper to the copper tun.

I shovel another twenty pounds of milled winter barley into the intake hopper. The grain hits the boiling water with a dull, heavy hiss. Sweet, thick steam billows across my face, stinging my blistered palms and sticking my linen shirt to my ribs.

My back screams from hauling six hundred pounds of grain up the granite cellar stairs. Vargun carried the last hundred-pound sack on his shoulder like an unearned favor. Then he vanished back up the service hoist, leaving me locked inside the stone box with a running boiler and a thirty-hour deadline.

He thinks solitary confinement grinds a brewer into compliance.

He forgets that yeast does its best work in the dark.

I haul back on the oak mash paddle. The mixture is thick as wet sand, dragging against my forearms until the muscles burn.

A sharp clink echoes above me.

Metal striking stone.

I freeze with the paddle locked in both hands.

The sound did not come from the locked oak door at the front corridor. It came from thirty feet overhead, inside the square brick chimney of the grain flue.

I do not turn my head immediately.

In Hrafnsker, when someone stalks you from above, looking up gives away your neck.

I let my gaze track the stone walls without shifting my stance. The brewhouse is thirty paces wide, built over a sunken drainage trench where wastewater collects before flushing into the river caves. Four massive secondary fermentation vessels sit along the north wall, each holding five hundred gallons of last week's raw wash. They are sealed tight with cast-iron dogs, cold and pressurized, their vent pipes routed to the ceiling exhaust flue.

Another scrape.

Soot drifts down through the iron vent grate directly above the mash tun.

Two bodies are crawling through the flues.

Not Vargun. Vargun weighs two hundred and twenty pounds of muscle and armor; he would have brought the whole brick chimney down in thirty seconds.

These are thin men. Infiltrators.

Fjalar's remnants.

I knew the dead bastard had cousins hiding in the lower sculleries. With Fjalar hanging from the gatehouse beams, his men have exactly twenty-four hours before Vargun rounds them up for the courtyard block. If they ruin the Maltar supply, the compound collapses into total riot. In the chaos, they might actually crawl out the main gates alive.

A leather boot sole drops from the flue.

A man drops onto the iron catwalk twenty feet above my head. He lands on his toes, silent as grease. A second man follows, slipping through the iron intake hatch with a bundle wrapped in greasy oilcloth strapped to his chest.

I recognize the gray wool rags. Fjalar's scullery runners.

The first man pulls a serrated trench knife from his boot. He has grease smeared across his cheekbones to cut the glare of my torchlight.

The second man unties the oilcloth bundle.

The white powder inside the bundle puffs into the warm air.

Quicklime.

Calcium oxide. Two handfuls of that alkaline poison into the boiling mash will spike the pH past nine, scorch the active enzymes, and curdle three hundred gallons of grain mash into an acidic sludge.

If that powder touches my wort, I am a dead woman.

"Quiet, brewer," the first one whispers from the catwalk. He points the iron blade at my chest. "Step away from the boiler valve and you get to live until morning."

He is lying.

Men who bring poison through a chimney do not leave witnesses with working lungs.

My heart gives a hard, violent thump against my ribs.

Fear is a chemical waste product. It clouds the eyes and slows the hands.

I let go of the mash paddle.

"Take whatever is in the dry stores," I say, keeping my voice flat and shrill, putting just enough tremor into my tone to feed their confidence. "The flour sacks are under the hoist. The bacon is salted in the cellar."

I take two slow steps backward.

My boot heel finds the raised rim of the granite drainage floor.

The two infiltrators exchange a glance. The one with the quicklime drops from the catwalk down to the floor, landing with a soft thud on the flagstones near the south wall. He is six paces away from the sunken drainage trench.

The man with the knife drops down after him, his boots skidding slightly on damp malt dust.

"We don't want bacon, girl," the knife-man says. He grins, showing teeth broken down to yellow stubs. "We want your batch dead. Then your new lord starves in the courtyard."

He steps toward the mash tun, his knife held low.

They are standing dead center in the depressed drainage basin.

The lower floor is built three feet lower than the entrance threshold, designed to catch boiling spills and funnel heavy waste toward the iron floor grating.

It is also an airtight pocket.

To my left, the copper bypass manifold connects the four pressurized secondary fermentation vats to the ceiling chimney. Each vat contains eighty pounds per square inch of pure, dense carbon dioxide—a cold, odorless, suffocating gas produced by four thousand pounds of active brewer's yeast.

Carbon dioxide is heavier than air.

Release it at ceiling height with an open exhaust, and it blows out the roof.

Release it at floor level with the exhaust dampers slammed shut, and it sinks like lead into the lowest point of the room.

My fingers touch the cold brass lever behind my hip.

"You really shouldn't dump lime into active wort," I tell them.

The knife-man pauses three paces away. "Why not?"

"Because alkaline salts ruin the copper lining," I say. "And I hate scrubbing copper."

I pull the iron damper chain with my left hand.

The overhead roof flue slams shut with a deafening clang that echoes off the granite vaults.

In the same breath, my right hand wrenches the brass bypass lever down hard.

The pressure seals on all four secondary vats burst open with a scream like tearing sheet metal.

High-pressure gas roars through the lower discharge nozzles.

A freezing cloud of invisible vapor floods out from the vat bases, sweeping across the floor like water breaching a dike. It does not rise. It rolls along the stone, heavy and dense, pooling directly into the three-foot sunken trench where the two men stand.

The torch on the center pillar flickers once.

Then it dies.

Not from wind. From lack of oxygen.

The brewhouse plunges into dim amber shadow, lit only by the red glow of the boiler firebox behind my back.

The knife-man lunges forward with an angry curse. "Kill her!"