The bronze needle bit into Lin Ke’s bone-skin with a sickening, high-pitched crunch.
It didn’t feel like flesh parting. It felt like driving a rusted finishing nail into a slab of stale dry plaster. The pain was dull, deep, and sickeningly cold, streaming from the center of his left forearm into his wrist until his fingers went numb.
Apothecary He leaned in closer, his watery, yellow-tinged eyes narrowed behind thick lenses of cloudy quartz. The old healer held the knurled grip of the needle between two nicotine-stained fingers. His ear was pressed against an ebony resonator tube resting against Lin Ke’s forearm.
“Listen to that,” He muttered, his voice raspy as unplaned cedar. “Hear that rattle?”
Lin Ke didn’t need the sound tube. He could hear the shaking inside his own jaw.
“Turning to stone,” Lin Ke said, his breathing slow and measured through his nose. “Insoluble stone deposits choking the blood-vessel canals.”
“Don’t give me your fancy clerk gibberish, boy,” He grunted, twisting the needle an eighth of a turn.
A sharp spike of agony lanced up to Lin Ke’s elbow. He didn’t flinch. He kept his right hand resting flat against the scarred apothecary bench, fingers curled loosely around his pocket ledger.
“It’s dry chalk,” He said, pulling the bronze needle free with a wet shluck. A tiny drop of dark, gritty ooze oozed from the puncture wound. “That damned Iron Marrow Manual the outer sect dumps on illiterate fire hands. It doesn’t cultivate iron bones. It petrifies living tissue. The marrow has stopped making fresh blood. It’s making lime.”
He wiped the needle on an alcohol-soaked rag, shaking his head with bitter familiarity.
“Hairline fracture along the lateral shaft,” the old man continued, tossing the needle into an iron dish. “You lifted something heavy or took a shaking shock. If you take a direct strike from an iron heavy club—or even a heavy hammer blow on the anvil—that radius will snap like a dried pine twig. It won’t mend, either. It’ll shatter into grey powder.”
“Treatment?” Lin Ke asked.
“Marrow-Nourishing Jade Broth,” He replied without looking up. He began grinding bitter-root in a stone mortar. “Steamed white-tusk marrow, seven-leaf spirit ginseng, and refined red stone oil. Three jars over six months will dissolve the superficial waste scum and lubricate the core.”
“The price.”
“Forty low-grade spirit stones a jar,” He said flatly. “A hundred and twenty for the course. Cash upfront. No credit, no sect vouchers, and no promises you won’t still limp when it’s over.”
Lin Ke reached into the inner lining of his hemp robe. His fingers brushed against four small, rough pebbles of cloudy spirit stone—his total net worth after surviving three months in the Seventh Ward.
“I have four,” Lin Ke said.
He let out a dry, hacking bark of laughter that ended in a wet cough.
“Four stones will buy you a bowl of boiled turnip greens and a clean linen bandage to wrap your arm before it falls off,” He said. He pointed a pestle toward the doorway. “Get back to your forge, Clerk Lin. Die on sect time. At least that way your burial urn gets stamped with Elder Wu’s official seal.”
Lin Ke didn’t move.
His eyes scanned the cluttered, damp pharmacy. everyone could feel the choking smell of scorched roots, sour vinegar, and boiled animal fat. On the wide clay hearth behind the counter, five blackened iron cooking pots simmered over low charcoal fire bowls.
Dense, fragrant steam billowed from the pots, rising straight toward the thatched ceiling and escaping through the soot-stained smoke hole.
Every puff of steam carried a sharp, healing aroma—volatile terpene compounds and active alkaloids boiling away into thin air.
Lin Ke tilted his head, his mind right away parsing the heat-powered losses.
Open-air reflux deficiency, he observed. Air boiling at surrounding pressure. Heat degradation of volatile active ingredients. Volume yield loss exceeding sixty percent.
He focused his intent.
Tianfu. Branch.
In the mental sandbox, Lin Ke took apart the apothecary’s primitive brewing process.
Apothecary He was boiling sixty pounds of valuable raw herbs down to two small jars of dark, thick, sticky syrup. The herbs were scorched at the bottom of the iron pots. Meanwhile, the lighter, most delicate therapeutic vapors flashed into the air and drifted over the valley like useless perfume.
Lin Ke drafted a blueprint in grey lines.
A sealed clay pot. A curved copper goose-neck riser. A coiled copper cooling tube sunk in a backup vessel filled with cold mountain runoff.
Counter-current heat exchange.
The steam rises, encounters the cold surface, condenses instantly, and drips into a collection flask without losing a single gram of volatile essence. The lower boiling heat prevents heat decomposition of the bone-soothing alkaloids.
Lin Ke cut the mental branch.
He slipped his left hand into his sleeve, found his iron metal pen, and pricked his thumb.
“Branch checked: main,” he whispered.
“Mumbling again,” He grunted, turning back to his mortar. “If you’re not buying salve, get out of my light. I have sixty pounds of bone-cooling waste scum to simmer before sundown, and half of it will turn to tar if the fire bowl drafts wrong.”
“Your process is losing sixty-five percent of its volatile yield to the ceiling,” Lin Ke said clearly.
He paused his pestle. He looked at Lin Ke over the top of his quartz lenses, his brow furrowing into deep, skeptical ridges.
“What did you just say?”
“The steam leaving those pots carries the active healing oils,” Lin Ke said. He gestured toward the simmering cooking pots. “You boil them uncovered at air pressure. The intense bottom heat chars the organic sugars into bitter tar. Meanwhile, the vapors that actually soothe inflamed tissue vent out through your roof tiles. Your extraction smooth speed is less than twenty percent.”
“Nonsense,” He sneered, though his grip on the pestle tightened. “This is the old family three-simmer decoction method of the Hundred Herb Pavilion! It has been practiced for four hundred years!”
“And for four hundred years, you’ve been throwing away two-thirds of your medicine,” Lin Ke replied deadpan. “I have no spirit stones. But I have two hours, a coil of hollow copper tubing from the ward’s scrap bin. An building solution.”
He stared at the young clerk. “What kind of solution?”
“A closed-loop water drops rig,” Lin Ke said. “I build it now, on your hearth. You give me the dregs of your healing roots—the scraps you usually discard after skimming. If my rig doubles your extraction yield of Bone-Soothing Salve from those scraps alone, you give me one jar of the packed distillate and a jar of raw bone-setting paste. If it fails, I give you my four spirit stones and sweep your pharmacy floor for a month.”
Apothecary He narrowed his eyes. The old man was cynical, bitter, and hardened by decades of watching outer students rot. But he was also fundamentally a tradesman. The prospect of free spirit stones—or double the medicine from worthless scrap—pulled at his mercenary instincts.
“Two hours,” He spat. “And you clean up your own mess.”
Lin Ke stepped out to the courtyard, retrieved his wicker tool sack. Then he returned with a ten-foot coil of flexible copper pipe, three clay fittings. A block of beeswax sealant he had scavenged from the smelting ward’s drafting office.
He worked with total, clockwork care.
He took a clay pot jug, drilled a tight hole through the wooden lid using his iron metal pen. Then he fitted the copper pipe into the orifice. He sealed the joint with molten beeswax and powdered lime.
Next, he bent the copper tubing into a tight, six-turn spiral coil, placing the coil inside a wide cedar tub filled with icy water drawn from the northern mountain spring behind the clinic.
At the bottom of the tub, the copper tube pierced the wood and drained into a clean glass vial.
“What’s that contrivance?” He muttered, crossing his arms and watching with deep suspicion. “A copper serpent?”
“A counter-current reflux steam cooler,” Lin Ke said, without looking up. “The steam ascends through the neck, enters the cooled copper spiral, and transfers its heat energy to the surrounding water jacket. The gas undergoes rapid phase change back into liquid. Zero sky venting. Zero heat scorching.”
Lin Ke took five pounds of bitter root dregs—wet, stringy pulp that He had already simmered once and tossed into the refuse pail—and packed them into the sealed pot with three ladles of spring water.
He set the pot over a modest bed of embers, keeping the flame banked.
Within fifteen minutes, the water inside began to hum.
Steam rose into the copper neck. It vanished into the coil sunk in the cold wooden tub.
Apothecary He stepped forward, holding his breath. He looked up at the smoke hole—no fragrant steam drifted toward the straw roof. The room remained fully free of healing odor.
Drip.
A drop fell from the copper spout into the glass vial.
Then another. Drip. Drip. Drip.
The liquid was not dark, muddy brown like He’s usual decoctions. It was pale, glowing amber, perfectly clear, with a rainbow-bright film of packed essential oils shimmering on the surface.
A heavy, packed aroma suddenly blossomed from the small opening of the vial—pure, clean, and piercingly cool. He carried the scent of pine needles, winter frost, and deep-earth minerals.
Apothecary He pushed Lin Ke aside and snatched the glass vial.
The old man uncorked it, dipped a trembling finger into the amber liquid. Then he touched it to the tip of his tongue.
His eyes widened until the whites showed fully.
“The... The cold essence,” He whispered, his jaw trembling. “It’s not scorched. The volatile marrow-soothing resin... It’s all here. From the refuse pile?”
“Refuse contains thirty percent leftover compounds,” Lin Ke said, step by step wiping down his copper fittings with a dry cloth. “Your old method was simply too crude to extract them. This steam cooler captures ninety-five percent of the leftover aromatics.”
He looked at the five cooking pots simmering on his hearth, then looked down at the tiny glass vial in his palm.
A pot of fresh herbs normally yielded half a cup of cloudy syrup after eight hours of boiling. With this copper serpent, he could produce three times that volume from half the ingredients, in a fraction of the time.
“By the Ancestors’ teeth,” He breathed. He turned back to Lin Ke, his cynical sneer fully gone, replaced by a mixture of shock and hungry skilled greed. “You... Where did you learn this alchemy? This isn’t sect doctrine.”
“Fluid dynamics and phase shifts,” Lin Ke said flatly. “It’s not alchemy. It’s plumbing. Do we have a deal?”
He swallowed hard. He walked over to his locked wooden cabinet, took down a heavy clay jar sealed with green wax. Then he set it on the counter with a dull thud. Beside it, he placed a smaller pot of thick, grey bone-setting salve.
“The green jar is Marrow-Nourishing Jade Broth,” He said, his voice unusually quiet. “A full jar. The grey pot is external bone-setting paste. Rub it into your forearm twice a day before sleep.”
Lin Ke reached for the jars, but He slammed a gnarled hand down on top of the lids.
“Listen to me, Lin Ke,” the old man said. He leaned across the counter, his watery old eyes dead serious. “This salve will patch the fracture. The broth will lubricate the dry friction in your canals. But it will not rebuild your skeleton.”
Lin Ke met his gaze. “Explain.”
“You have glass spirit veins,” He said, his voice dropping to a conspiratorial whisper. “Narrow, rigid, brittle. And now your bones are turning to chalk. The broth will only buy you three months, maybe four, before the hardened melted rock waste finishes choking the marrow entirely. When that happens, your own skeleton will eat itself from the inside out.”
“Then I have three months to refactor the foundation,” Lin Ke said. He slid the jars toward himself.
“You can’t refactor bone, boy!” He snapped. “You’re a mortal-born fire hand! If you try to force high-grade spirit Qi through a crumbling skeleton, you won’t breakthrough. You’ll collapse into a sack of broken fine china!”
“Noted,” Lin Ke said, slipping both jars into his hemp satchel. “Leave the water jacket full. Replace the tub water when it gets warm. Good day, Apothecary.”
Lin Ke stepped out of the clinic into the late afternoon glare. The air in the valley was cold and thin. It carried the metal bite of the distant iron foundries.
He adjusted the satchel over his shoulder. The dull throb in his left forearm was still there. But the bone-setting paste offered a clear, temporary buffer.
He turned down the narrow flat stone slab alley leading toward the Seventh Ward’s storage yards.
Fifty paces down the path, near the corner of the grain warehouse, two figures in dark silk robes stepped behind a stack of empty crates.
Lin Ke didn’t turn his head. He kept his stride steady, his boots clicking rhythmically against the stone.
In the glow of a dirty rain puddle near his feet, he saw the yellow crane crest stitched on their silk sleeves.
Grand Fortune Merchant Clan, he noted coldly. Zhao Wuji’s outer edge scouts. Logging my visits. Tracking my physical deterioration.
They knew his bones were failing. They were counting the days until his skeleton gave out under the fire load.
Lin Ke’s lips tightened into a thin, merciless line.
Let them log it, he thought, feeling the heavy glass vial resting against his ribs. A system crash only looks certain until you deploy the patch.