The Counterweight

While Vance held Corin's attention beneath the shield line, I dropped to a crouch and scrambled along the maintenance conduit behind the stone arch. The physical ache in my joints was sharp and burning, my lungs starved of air by the humid sulfur fog, but the layout of this chamber was burned into my memory from the loop before.

Above the central manifold hung the secondary counterweight damper: a four-hundred-pound block of pig iron suspended on an indexing ratchet. In the previous loop, I had dropped it to shatter his collarbone before he overpowered me and took my throat.

This time, the trip lever was on my side of the gantry.

I pulled an eighteen-inch iron pry bar from the wall-mounted tool rack beside the conduit. The cold metal bit into my palm, but my fingers closed around it with stubborn intent.

Corin dropped from the upper catwalk with the fluid grace of an acrobat, landing lightly on the high gantry rail twenty paces above Vance. In his left hand, he held a cocked hand-crossbow; at his right hip hung the thick, polished brass cylinder bearing Cleary's master cipher.

He raised the bow, aiming past Vance's shield toward the open walkway.

"Ironwright!" I shouted, stepping out onto the exposed platform beside the ratchet housing. "Duck!"

Corin swung his bow toward me, his eyes widening behind the brass visor as he recognized the envoy he thought was trapped in an upper cell.

Click. Clack. Click.

The escapement gear hit its fourth stroke.

I drove the iron pry bar straight into the teeth of the index cam.

The kinetic mechanism seized with a screech that set my teeth on edge. The four-hundred-pound counterweight cradle lurched in its tracks, its guide cable snapping taut with the sound of a whipcrack. The sudden transfer of torque sheared the anchor bolts holding Corin's catwalk to the cavern wall.

The entire iron gantry tilted forty-five degrees into the void.

Corin lost his footing with a strangled curse, his crossbow discharging wildly into the ceiling as he slid down the slick metal grating. He caught a safety cable with one arm, dangling directly over the churning sluice flues, his boots scrambling for purchase against the wet stone.

Vance was already moving.

He did not hesitate. He vaulted onto the lower crossbeam, using the momentum of his jump to slam the heavy bronze rim of his shield into Corin's exposed ribs.

The crack of breaking bone echoed above the roar of the water.

Corin lost his grip on the cable and crashed down onto the stone floor of the manifold, rolling twice before coming to a stop against the master valve housing. His respirator mask cracked against the iron floorplates, hissing as the seal failed.

Vance landed two paces away, his trench blade leveled at the courier's throat before the boy could draw his knife.

"Drop the steel," Vance said. The point of his blade touched the hollow of Corin's neck, drawing a single bead of dark blood.

Corin coughed, spitting a mouthful of crimson foam onto the rusted plates. His right arm hung useless, the collarbone splintered beneath his padded tunic, but his gray eyes remained bright with frantic malice. He let his short blade slide from his fingers, clattering into the drainage gutter.

I walked over to them, my chest heaving, the iron pry bar still gripped in my shaking right hand. My left arm hung limp, trembling violently as the strain of the jump caught up with my failing nerves.

"The case," I said, my voice hoarse from the sulfur mist.

Vance reached down with his left hand, severed the leather harness with the edge of his blade, and tore the heavy brass cylinder from Corin's chest. He tossed it to me.

The metal was heavy, cold, and intricately engraved with the interlocking cog-and-trowel mark of the Chief Kinetic Engineer. I pressed the release notch at the base. The spring groaned, popping the threaded cap free to reveal a tightly rolled spool of waxed linen parchment covered in precise mechanical drafting lines and ink-stamped operational timetables.

It was the master blueprint of the Brass Wheel's lower siphon network.

"You have the layout," Vance said, keeping his eyes locked on the courier. "Does it show the sluice override?"

I unrolled the top edge of the linen against my knee, tracing the fine black lines with a trembling thumb. "The override is manual. The pin is behind the secondary pressure valve on the third bulkhead. If we throw it, the water bypasses the lower gorge completely. The trade wagons will cross dry."

"Then do it," Vance said.

"Wait," Corin wheezed from the floor. He let out a wet, bubbling laugh that ended in a harsh cough. "You think... you think you're clever, Fletcher?"

I paused, looking down at him. The boy was barely twenty, his skin pale and slick with sweat beneath the smudge of soot and oil.

"I know Cleary hired Vance's company to butcher the convoy," I said evenly. "I know he planned to flood the culverts to drown whoever survived the High Harrow. And I know he needs the proxy war to convince the Court Council to seal the border gates for another generation."

Corin's lips peeled back from blood-stained teeth in a twisted grin. "You know nothing about the clock, envoy."

Vance pressed the tip of his blade a fraction deeper. "Speak plainly, boy."

"Thirty days?" Corin rasped, his eyes darting between us with dying spite. "You think you have thirty days before the unsealing ends? Look at the bottom margin of that draft, Fletcher. Look at the gear ratios for the Great Escapement."

My fingers tightened on the parchment. I pulled the linen down, exposing the lower technical ledger stamped with Cleary's personal seal.

The ink was fresh, the annotations written in the Chief Engineer's neat, sloping script:

Primary kinetic cycle accelerated via subterranean siphon bypass. Master escapement tooth will clear the final gate-latch at the seventy-second hour. The border drops permanently at midnight of Day Three.

The air went out of my lungs as if I had been struck in the ribs with an iron stave.

Three days.

Not thirty.

Cleary was not waiting for the traditional month-long generation window to conclude. He was using the kinetic energy stolen from the lower siphon to force the Brass Wheel through its thirty-day cycle in less than seventy-two hours, locking every trade wagon, every envoy, and Vance's entire mercenary company inside the Barrow-Mark forever.

"He's dropping the master tooth," I whispered, the paper crinkling under my grip. "In three days."

"Three days," Corin whispered, his head slumping back against the cold iron of the valve. "And none of you are ever walking out."

Vance did not move. His blade remained steady at the boy's throat, but his gray eyes cut sideways toward me, dark and unreadable in the mist.

"Is that true, Fletcher?"

"It is on the engineering schematics," I said, looking up from the parchment to meet his gaze. "He has already engaged the bypass gears. We don't have a month to negotiate an exit. We have barely sixty hours before the gates slam shut and the mechanisms weld themselves in place."

The water roared in the darkness below, churning through the teeth of the great brass wheels.

Vance looked from the linen in my hands to the dying courier on the stones, his jaw tightening into a line as hard and unyielding as the iron plates beneath our boots.

"Then we have work to do," he said.