The war-boar’s steel tusks were notched from old skirmishes, but its rider’s scowl was sharper still.
Dwarf Trade Envoy Thorgan Ironvein sat upon his leather saddle with his arms folded across a chest as wide as an ale cask. His iron war-pick rested in its sword sheath. But the two-foot sliding measuring tongs hanging from his neck caught the morning sun with a polished, golden gleam.
Behind him, five mounted dwarven guards held their short heavy steel crossbows resting across their thighs, watching Kenneth Drake’s spearmen with narrow, calculating eyes.
“Borin,” Thorgan said, his deep bass voice echoing off the stone vaulting like an iron bell. “You were sent south two seasons ago to trade for timber and grain. Instead, we find the Lost Gate swung wide, the sacred hinges dripping with stinking cod liver. An army of lowland shovel-men standing in the old family portal.”
Master Borin Bronze-Lung stepped forward, tucking his thumbs into his belt. “I was sent to find metal and fuel, cousin. And I’ve found both. This is Lord Giles Croft, Baron of Grey Crag.”
Thorgan snorted through his flat nose, a spray of grey vapor pluming into the chill air. “A human baron. A breed known for three things: bad debts, crooked stonework, and walls that fall over in the third winter.”
“Our walls don’t fall over,” Giles said calmly, stepping forward with his notebook open. “And the lubricant was a seventy-thirty mix of rendered fish animal fat and stone spirits, which reduced the multiplier of static friction from zero point six to point zero eight. If your gatekeeper had applied an animal fat swab once every fifty years, we wouldn’t have needed the screw jacks.”
Thorgan slid down from his boar with surprising agility. His heavy boots struck the dark rock pavers with a solid thud.
He walked directly up to Giles, his slate-grey eyes level with Giles’s breast pocket.
“You talk of friction like a guild scholar,” Thorgan rumbled. “Humans love words. They build arches out of mud and prayers. When the mortar rots, they blame the gods.”
He reached to his chest, unhooking the massive brass fine-scale measuring tongs with practiced respect.
The tool was an old family masterpiece of Khaz-Drak metalcraft. Three pounds of heavy, polished brass with silver inlaid scales, engraved in sixty-fourth-inch graduations down the beam.
“This is the Gauge of Durin-Tor,” Thorgan declared, holding the instrument high. “Forged in the deep heat of the Founding Age. It has checked the bore of our cannons and the fit of our lock-gates for four hundred years. If your work deviates by so much as a tenth of an inch, human, your treaty is forfeit and this road is sealed.”
Lady Millicent Croft stepped up beside Giles, her tally-book open and her quill dipped in fresh ink.
“We have sixty tons of winter wheat currently stored in dry cribs,” Millicent said, her tone as dry as parchment. “And three hundred seasoned white oak baulks cut to twenty-foot lengths. If Clan Khaz-Drak prefers to eat stone measuring tongs during the winter blizzard, we can easily sell our grain downstream to Duchess Rowena.”
Thorgan’s left eyebrow twitched.
He ignored her, turning his gaze toward the eight-inch copper drain tube pipe that arched over the red stone pylon and snaked up the granite dyke.
“Copper,” Thorgan scoffed, striding over to the pipe and tapping it with his measuring tongs jaw. “Thin-walled rolled sheet, soldered with soft pewter. Look at that collar seam! You probably have an eighth-inch run-out across that joint!”
He slid the moveable jaw of the brass measuring tongs along the beam. He clamped the polished tips across the soldered sleeve.
He squinted at the silver fine-scale markings, his lips moving as he read the scale.
“Hah!” Thorgan barked. “Eight inches and thirty-two thousandths! The sleeve is over-gauge by more than a thirty-second! Slop! Lowland play!”
Giles didn’t move.
He glanced down at the measuring tongs, then looked at the dwarf’s thick, calloused thumb pressed firmly against the brass beam.
“The sleeve was turned to exactly eight point zero inches at sixty degrees Fahrenheit,” Giles said mildly. “Your measuring tongs is currently reading thirty thousandths high.”
Thorgan’s face darkened to the color of a bruised turnip. “Are you calling the Gauge of Durin-Tor a liar, boy?”
“The gauge isn’t lying,” Giles said. “The physics are simply running without your consent.”
He took his pencil and tapped the brass beam of Thorgan’s instrument.
“You have been holding that measuring tongs in your bare right hand for twenty minutes while riding a heated war-boar,” Giles explained.
“The multiplier of linear heat swelling for yellow brass is about nineteen millionths of an inch per degree Celsius,” Giles continued. “Your hand heat has heated the twenty-four-inch beam by nearly twenty-five degrees above surrounding air heat.”
Thorgan blinked, his mouth opening slightly.
“The brass has swelled lengthwise by nearly eleven thousandths,” Giles said. “Plus, your sliding jaw is slightly cocked because the guide gib has worn unevenly on the lower rail, introducing a cosine posture error. If you want an accurate measurement, dunk that tool in the cold drainage ditch for two minutes to bring it to heat balance with the pipe, then re-zero the fine-scale.”
Silence fell across the portal apron.
Borin Bronze-Lung covered his mouth with his hand, his eyes dancing with suppressed glee.
Toby Karr grinned openly, nudging Kenneth Drake with his elbow.
Thorgan stood motionless for five long seconds. His beard bristled.
“Dunk it?” Thorgan growled. “Dunk the sacred old family gauge in ditch water?”
“Unless you prefer measuring heat swelling instead of copper width,” Giles said. “It makes no difference to me. The water continues to flow either way.”
With a low, rumbling curse, Thorgan turned on his heel.
He stomped to the edge of the drainage channel, knelt down. Then he plunged the three-pound brass measuring tongs into the icy spring current running from the drain tube discharge.
He held it beneath the rushing water for three full minutes, glaring at the rocks.
When he pulled the tool out, water streamed from the silver scales.
He wiped the jaws with his wool sleeve, checked the index zero against the closed stop. Then he walked back to the copper pipe.
He set the measuring tongs jaws across the soldered sleeve once more.
He slid the fine-scale into contact. He tightened the knurled thumb-screw.
He bent down, bringing his nose within two inches of the silvered marks, squinting until his eyes were narrow slits.
His hands stopped moving.
The jaw rested at exactly eight inches and one-thousandth of an inch.
Thorgan’s breath caught in his throat.
He tapped the gauge gently, re-checked the posture mark. Then he looked up at the copper channel curving gracefully over the twenty-foot granite dyke.
“One thousandth,” Thorgan whispered. His voice was no longer a roar. It was a stunned, reedy squeak. “He eyeballed thirty thousandths of hand-heat with his naked eye.”
He slowly looked at Giles, his gaze shifting from irritation to a kind of dazed, superstitious terror.
“You... You read the spreading of brass from six paces away?”
“It’s basic high-school physics,” Giles said, folding his rule and sliding it into his vest. “Now, are we going to discuss the heat-proof kaolin clay, or do I need to explain why your boar’s iron horseshoes are wearing faster on the outside rim?”
Thorgan hastily unhitched a heavy leather satchel from his boar’s pack-saddle.
He dropped the satchel onto the threshold stone with a heavy, metal clink.
Inside lay two smooth, ivory-white bricks wrapped in oiled sheepskin. A heavy tube-shaped crucible turned from solid crystal-clear graphite.
“Kaolin from the high white pits of Mount Thurn,” Thorgan said, his voice respectful and subdued. “Sixty-five percent alumina, twenty-eight percent quartz dust, less than half a percent of iron oxide. It will withstand three thousand degrees of fire without softening a hair. And the crucibles are turned from virgin vein graphite.”
Giles took one of the white bricks, weighing it in his palm. He scratched the surface with his penknife.
The texture was dense, smooth, and greasy to the touch, with zero grit.
“Excellent heat-proof stock,” Giles approved. “Low plasticity, minimal shrinkage on firing. This will form the bosh and hearth lining for our blast fire.”
Lady Millicent stepped forward, presenting a two-page parchment drawn up in neat, elegant ledger hand.
“The terms,” Millicent said briskly. “Forty tons of raw kaolin clay and twenty graphite crucibles delivered to the portal within fourteen days. In return, Grey Crag guarantees free transit along the drainage canal right-of-way, forty tons of winter grain upon delivery, and first purchase rights for your high-seam hard coal at sixteen silver pence per ton.”
Thorgan didn’t even read the second page.
He pulled a small iron signet ring from his tunic, pricked his thumb with his dagger. Then he pressed a bloody thumbprint into the wax seal at the foot of the document.
“Clan Khaz-Drak signs,” Thorgan said, bowing his head until his copper-braided beard brushed the dark rock stone. “Any man who can see the breath of metal with his naked eyes has the blood of the First Smiths in his marrow. The Under-Pass is open. Our wagons will roll at dawn.”
The dwarven riders turned their mounts back into the vaulted shadow of the mountain. Then, Toby Karr ran his fingers across the ivory-white kaolin brick.
“Lord Giles,” Toby said, his voice hushed with excitement. “Is it really true? Can this clay survive heat that would melt granite?”
“It doesn’t just survive it,” Giles said, climbing into the carriage beside Millicent. “It reflects it. Granite spalls because its quartz grains expand at different rates under heat shock. High-purity kaolinite forms mullite crystals when fired above twelve hundred degrees. The crystals interlock, creating a baked-clay matrix that holds its shape even when liquid iron is boiling inside it.”
Kenneth Drake swung up into his saddle, glancing back at the great open portal.
“And the dwarves?” Kenneth asked. “Can we trust them to keep the peace?”
“A dwarf who respects measuring tongs will always respect a contract,” Giles said. He pulled his pocket watch to check the hour. “A dwarf who respects measuring tongs will always respect a contract,” Giles said. He pulled his pocket watch to check the hour. “They think in thousandths of an inch. That makes them predictable, Kenneth. And in logistics, predictability is worth more than a regiment of heavy cavalry.”
Kenneth looked along the straight line of the Under-Pass road. There, the distant lanterns of the dwarven vanguard were fading into the cool mountain dark. A slow smile touched the sapper’s scarred mouth.
“A flat road through the world’s spine,” Kenneth murmured. “The High Judge’s spies will spend three months wondering how our grain wagons vanished into thin air.”
“Let them wonder,” Giles said, signaling the driver with his cane. “Now let’s head back to the kiln terrace. We have ten thousand firebricks to press before the frost sets in.”