Beneath the vaulted foundations of the Hero Monument, the underground air was ice-cold and heavy with the stone stench of wet dark rock and decaying river lime. Tomas Reed stepped carefully along the narrow plank narrow high walkway suspended above the churning intake race. The roar of the mountain river rushing through the underground water gates rang through the soles of his boots. It shook the bones of his legs with the crushing force of three thousand tons of impounded water.
Beside him, Mirelle Voss walked with the slow, steady pace of a graveyard keeper. Her dark wool skirts were held away from the slimy stonework. In her left hand she carried a small zinc bullseye lantern. Her right arm cradled the battered cedar box containing Oren Voss’s tin bird. The faint, clockwork tick of the clockwork gearwork was swallowed whole by the underground thunder. But she held the wood against her ribs as if protecting a newborn child from the river gale.
Aven Lark, the retired guild artificer, knelt at the center of the iron narrow high walkway, his eighty-year-old knees cushioned by an oiled leather pad. His white hair was tied back with a greasy hemp cord. His horn-rimmed magnifying lens reflected the pale, eerie living-glow blue of the soul-coupling coils. Before him stood the central core housing. A five-foot bronze metal tube crusted with green rust and sealed with thirty-six forged iron lock-pins.
“Look down through the quartz watching slit, porter,” Aven Lark murmured. He pointed with a long brass-tipped fine-tuning probe. “Tier One holds the common weavers. Tier Two holds the draymen and cooper apprentices. But down at the foundation ring—where the high-pressure uplift pressure reaches eighty pounds to the square inch—they needed an anchor with heroic pulling thickness. They needed a man who had sworn the high town promise.”
Tomas leaned over the bronze rim. He peeked into the murky depths of the high-pressure liquid silver bath. Suspended within the glowing blue matrix of static-electric coils hung an eight-sided bronze plate, its surface etched with the deep, angular glyphs of the Lantern Company. At its center, surrounded by the linked seals of the original expedition, was the stamped name: Oren Voss.
“They told the city my father abandoned the line,” Mirelle said, her voice devoid of tears, cold as the granite beneath their boots. “They carved his name on the monument above our heads, called him a fallen guardian, and buried an empty cedar coffin in the High Ward cemetery. All the while, his actual signed name was bolted to the floor of this sewer, holding back the water that should have been carried by honest stonework and paid water gate-keepers.”
“Oren didn’t abandon Bellwether,” Tomas said, adjusting the sling supporting his injured arm. “He refused to turn the wheel that drowned the seven communities. Holt and Vey realized he wouldn’t pull the emergency lever to drown the low cottages. Then, they struck him down at the gate, forged his give-up. Then they dropped his pledge into the foundation ring to keep the drain tube stable. This isn’t an engine of protection. It’s a rig of murder disguised as public work.”
Aven Lark ran his calloused thumb along the static-electric discharge ring. “If we break his anchor while the head of water is above the twenty-foot mark, the foundation ring will shear like green ice. The high-pressure back-surge would tear through the North Culvert and swamp the entire South Basin before morning. We can’t touch Oren’s plate until the low tide drops the river to the doorstep mark. The stone bypass takes the weight.”
Mirelle knelt beside the old artificer. She set her zinc bullseye lantern on the wet iron grating so its focused beam cut straight down through the quartz check pane. Inside the cedar box under her arm, the repaired tin bird gave a faint, dry click as the shaking of the intake race shivered through the soles of her boots. “Show me the locking pins, Master Lark,” she said, her voice steady against the underground roar. “When my father built the field-couplings for the Lantern Company, he always cut a reverse safety groove into the third pin so a jammed collar could be backed out with a wrench if the liquid silver overheated.”
Aven Lark adjusted his horn-rimmed lens, leaning closer to the green rust-crusted pipe rim at the base of the metal tube. With the tip of his brass fine-tuning probe, he scraped away a quarter-inch crust of crystal-hardened stone salt and gray animal fat grease from the third iron bolt. Beneath the rusting, a tiny double-beveled notch appeared in the collar seat. Oren Voss’s clear bench mark, chiseled forty years ago before the expedition ever marched north.
“He cut the relief groove even on the master ring,” Lark whispered, his breath clouding in the icy mist rising off the race. “Holt’s foundry crew drove thirty-six dead-bolts through the upper casing to make sure no one could ever open the metal tube without shattering the quartz, and none of them knew enough honest smith-work to look at the bottom collar. If we bleed the liquid silver pressure through this relief cock first, the eight-sided plate will drop clear of the upper jaws without triggering the recoil wards.”
Tomas crouched beside them. That kept his left forearm tucked tightly inside the black wool sling against his ribs so the damp vault draft wouldn’t stiffen his healing wrist tendon. With his right hand, he unfastened the brass clasp of his waterproof leather satchel. Then he drew out the parchment diagram they had recovered from Caldus Marr’s cellar safe. He held the sheet near the bullseye lantern, matching the ink numbers on the margin against the stamped numerals around the bronze pipe rim.
“There are six backup grounding lugs bolted into the dark rock stone base,” Tomas said, tracing the diagram with his right forefinger. “Look at the fourth lug on the east face. The copper braid has been sawed half through and packed with red sealing pitch to hide the gap. Someone rigged this metal tube so that if a secret mechanic tried to pull the upper pins from the narrow high walkway, the whole static-electric load would arc straight into the iron walkway.”
Aven Lark lowered his lantern and peered under the lip of the dark rock stone base, his pale eyes narrowing behind his lens. “That’s Darven Holt’s work—or the work of a trade ring saboteur paid to guard his reputation. A man standing on these wet planks with an iron wrench would be cooked inside his boots before he turned the second bolt. By going through Oren’s bottom relief collar with padded copper tongs, we bypass the upper circuit entirely.”
Mirelle reached out with her bare right hand, her thumb still purpled from the earlier ward-recoil. Then she touched the cold bronze rim directly above her father’s underwater plate. Through the thick quartz glass, the blue static-electric glow pulsed in slow, rhythmic beats that matched the heavy thud of the intake turbine below them. “For thirty-nine winters I walked past the granite monument on the walkway and listened to schoolmasters tell the parish children how Oren Voss gave his life in the mountain breach,” she said quietly. “Every winter when the river rose, he was thirty feet under the cobblestones, holding up the floor of the men who murdered him.”
“He held the floor for the people in the low wards too, Mistress Voss,” Aven Lark said gently. He wiped his brass probe on his oiled leather knee-pad. “The engine was a monster. The men who locked him into it were thieves. But Oren’s mark on that bronze kept the liquid silver column from splitting. Just then, the Great Frost cracked the northern under-road drain in Year Nineteen. He did his work cleanly, even in the dark. Tomorrow morning, we let him put the load down.”
Tomas measured the clearance between the dark rock stone base and the narrow high walkway support posts with his knotted cord, jotting the exact span—four feet, seven inches—into the margin of his field book so Jory and the quarrymen would cut the timber stacked timber frame to the exact height. Above their heads, through six feet of mortared granite and street cobbles, the faint iron clatter of a night patrol wagon rolled across the monument square and faded toward the High Ward.
Mirelle stood up, brushing the wet lime dust from her mourning skirt. Then she tucked the cedar box firmly beneath her shawl. “How long will it take to drain the liquid silver bath once the bypass gates take the river, Master Lark?”
“Seventeen minutes to bleed the pressure into the iron catch-flasks, and four minutes to back out the reverse collar,” the old artificer answered. He rose stiffly from his leather pad. “Provided the river drops to the winter doorstep mark on schedule and no one opens the upper lock gates to flood us out of the vault.”
Tomas drew his master ledger from his coat, checking the brass float gauges installed along the water chute wall. “The low-tide window is our only margin. When the tide turns at dawn, the river drops six feet in two hours. That’s when the drain tube slows. That’s when we uncouple Oren Voss from the city’s debt.”