Chapter 811: Siphon Diagram Astonishes All, Mechanical Principle Defies Common Knowledge

The Workshop in the rear courtyard of the Zongguan Fu in Tongwan City covers a little more than three mu, normally a place for forging weapons and repairing farm tools, but after being requisitioned tonight its appearance changed completely.

Twelve iron furnaces were hauled into the Workshop overnight; each furnace chamber was packed with premium charcoal, and the flames turned the entire Workshop's vaulted ceiling a blazing red.

Three hundred of Xiazhou's top craftsmen were urgently summoned from various counties; they squatted, stood, some kneading old calluses on their hands, others wiping sweat from their foreheads with their sleeves, and everyone's gaze fell on the gigantic workbench at the very center of the Workshop, illuminated brightly by four copper lamps.

Chen Yan removed his Great Cloak, rolled his sleeves up layer by layer to his elbows, revealing a firm, muscular forearm.

Hongye took the Great Cloak from his hands and stepped back to the pillar beside the Workshop's doorway.

Zhang Wenqian stood on the left side of the workbench, Gu Yuci stood on the right, Lu Ming and Ye Zhuxi squeezed into the back row, Chu Ci stood at the outermost edge, tiptoeing to look inward.

Chen Yan picked up a charcoal stick with a charred tip from the edge of the workbench and began drawing on the massive pine board that measured three zhang long by two zhang wide.

The lines fell quickly, each stroke bearing a strange curvature that none of the craftsmen present could comprehend.

A gigantic inverted‑U‑shaped tubular structure gradually took shape on the board; one end of the tube was immersed in a water surface labeled "Tianchi," the other end hung above a low area marked "Yinshuiqu," and the curved middle spanned over a ridge labeled "Sheer Cliff."

After the whole picture was finished, the Workshop fell silent for five breaths.

Zhang Wenqian was the first to speak, his voice tinged with a restrained bewilderment.

"Pillar of the State, forgive my ignorance, but this tube crosses the ridge—how can water flow from a low place to a high place?"

Chen Yan set the charcoal stick on the table and tapped his finger on the curved section of the tube that crossed the Sheer Cliff in the drawing.

"Do you think water can only flow from high to low?"

Zhang Wenqian's brows knit together.

"This is the law of Heaven; for millennia no one has questioned it."

Gu Yuci interjected, his voice steady yet clearly doubtful.

"I am not versed in hydraulics, but in marching and fighting I have diverted mountain spring water; indeed I have only ever seen water flow downhill, never uphill."

Lu Ming scratched the back of his head, his broad, simple face full of bewilderment.

"Pillar of the State, this thing looks like a large bamboo tube bent over, but how could water possibly crawl up the slope by itself—surely it can't grow legs, can it?"

Ye Zhuxi glanced at him without speaking, but her brows also furrowed slightly.

Chu Ci stood at the outermost edge, neck stretched long, stared at the diagram for a long while, and muttered under his breath.

"If the Pillar of the State is right, then the common knowledge of millennia is entirely wrong."

Chen Yan did not rush to explain; he turned around and raised his hand toward the bewildered craftsmen in the Workshop.

"Bring two wooden basins over, and give me a hollow bamboo pipe three chi long."

Two craftsmen hurriedly fetched two wooden basins used for washing hands from a corner, and another handed over a hollow bamboo pipe normally used for pouring molten copper.

Chen Yan placed the two basins side by side at opposite ends of the workbench; one was filled with water, the other empty.

He lifted the hollow bamboo pipe, inserted one end into the water‑filled basin, then sucked hard on the other end with his mouth.

The water rose swiftly inside the pipe, passed the highest bend of the bamboo tube, and surged toward the opposite end.

Chen Yan aimed the outlet of the bamboo pipe at the empty basin and released his mouth.

The stream gushed continuously from the pipe's outlet into the empty basin, never stopping or breaking.

The water level in the filled basin fell at a visibly rapid rate, while the level in the empty basin rose at the same speed.

The water, after crossing the highest point of the bamboo pipe, flowed upward.

The air in the Workshop seemed to have been split open from the middle.

The mouths of the three hundred craftsmen opened in unison, and a few older artisans even rubbed their eyes, thinking they were seeing things.

Zhang Wenqian's breathing grew shallow and rapid; his fingers clenched and released repeatedly, his gaze fixed on the bamboo pipe still spouting water.

"How… how could this be…?"

Chen Yan released his fingers from the bamboo pipe, letting the water continue to flow on its own.

"You think it's impossible because you only see the water, not the thing pressing down on it."

He drew a circle in the air with his finger.

"Between heaven and earth there is an unseen, untouchable substance; I call it air pressure."

Zhang Wenqian's mouth opened slightly.

"Air pressure?"

Chen Yan nodded.

"You've held your breath underwater before, right?"

Zhang Wenqian hesitated.

"I swam in a river when I was a child."

Chen Yan tapped the water surface in the basin with his finger.

"When you look up from the bottom of the water, do you feel a tightness in your chest, as if something is pressing on you?"

Zhang Wenqian's brows relaxed slightly.

"Indeed so."

Chen Yan withdrew his hand from the water surface and pointed upward.

"The same principle applies when you stand on the ground: dozens of miles of air above your head press down on you, yet you don't feel it because you have been accustomed to that pressure since birth."

His finger withdrew from the sky and landed again on the bamboo pipe.

"When this pipe is filled with water, the water column at the outlet is lower than at the inlet; the air pressure above pushes the inlet's water surface down, forcing water into the pipe, over the highest point, and out through the outlet."

He lifted the bamboo pipe, and the flow stopped instantly.

"As long as the outlet of this pipe is lower than the inlet's water surface, and the pipe remains unblocked, water will keep flowing, flowing, until the inlet's water level drops to the same height as the outlet."

Zhang Wenqian's hands trembled twice before him; he inhaled sharply, his voice trembling with an excitement he could barely contain.

"So you mean, the water surface of Tianchi is higher than the mouth of Yinshuiqu, and as long as a sufficiently long pipe spans the Sheer Cliff in the middle, the air pressure will continuously push the water to flow out?"

Chen Yan tossed the bamboo pipe back onto the table and clapped his hands.

"Old Zhang, your mind works fast enough."

Zhang Wenqian leaned his body forward two inches, his eye sockets slightly reddening.

"Minister, if this method succeeds, it will not only solve Xiazhou's drought; any place in the world with mountains and water could use this technique to divert water to irrigate fields!"

In the Workshop, three hundred craftsmen at that moment burst into a buzzing murmur; some slapped their thighs in approval, some knelt on the ground and kowtowed toward Chen Yan, and many simply widened their eyes, their faces filled with shock after having their understanding completely overturned.

Chen Yan gave them little time to digest.

He turned and walked back to the massive blueprint, the charcoal stick back in his hand, drawing circle after circle of markings on the pipe's structural details.

"You understand the principle; now tell me the difficulties," he said.

His charcoal stick drew a circle at the pipe's thickest section.

"The straight-line distance from Tianchi to Yinshuiqu is three li, the Sheer Cliff's highest point rises four zhang above Tianchi's water surface, and the pipe's total length must be at least five li."

He pressed the charcoal stick heavily at the pipe's joint.

"The pipe's diameter must be at least two chi wide, otherwise the water flow won't suffice to irrigate the spring fields of twenty‑eight counties."

His finger drew a cross‑section of a sealing gasket at the joint.

"Each pipe segment's joint must be tightly sealed—no water may leak, no air may enter. If any link loses its air, the Air Pressure effect disappears and the water stops."

He set the charcoal stick down, turned, and looked at the three hundred craftsmen.

"Wrap the wooden pipe with iron sheet, brush the interior three times with tung oil, fill the joint with raw lacquer, and bind the exterior with iron rings."

His voice deepened.

"Within ten days, the Duke wants to see the entire five‑li pipe completed."

A grey‑haired elder craftsman rose shakily, his voice tightening.

"Minister, a five‑li pipe would consume tens of thousands of jin of iron sheet alone; our Xiazhou iron ore reserves …"

Chen Yan cut him off.

"The Duke will handle the iron ore; just tell the Duke whether we have enough craftsmen and whether their skill is adequate."

The elder craftsman clenched his teeth.

"We barely have enough manpower, but ten days is too tight; if the joint sealing is poor …"

Chen Yan stepped before him, lowered his head, and looked at him.

"If you succeed, you'll be granted a hundred mu of good fields; if you fail, you know what those Flagpoles in the square are for."

The elder craftsman's knees softened briefly, and he gripped his iron hammer tighter.

"I, an old man, will risk my old bones to serve the Minister!"

Chen Yan patted his shoulder, turned, and walked toward the Workshop's Damen.

"Begin work, rush through the night; the iron furnace must not go out, and the workers must not rest."

At the moment he stepped out of the Damen, the clang of iron hammers in the Workshop roared, the tinkling metal collisions echoing for several li in the night wind.

Gao Jiong waited for him in the shadows outside the Workshop.

"Minister, we've captured those three rats,"

Chen Yan halted.

"Speak,"

Gao Jiong pulled a surveillance record from his chest and whispered at a volume only two people could hear.

"Three Qi State covert agents, disguised as itinerant peddlers, have been operating at the border of Ningyuan County and Qinggui County for at least half a month."

His finger tapped a line on the record.

"Shuyi's Hidden Agent discovered fresh footprints and residual Poison powder by the Shuizao on Tianchi's east side; after comparison, the three suspects' trail was pinpointed."

Chen Yan's finger slowly rubbed the hilt of the knife at his waist.

"They intend to poison Tianchi?"

Gao Jiong bit his tooth.

"Not only poison; Shuyi's men uncovered a Mifeng hidden in the slatted compartment of one peddler's shoulder pole, and the Mifeng contained three characters."

Chen Yan turned his head to look at him.

A sinister curve formed at Gao Jiong's mouth.

"Burn the Workshop."

Chen Yan's finger paused on the hilt.

"Where are the people?"

Gao Jiong answered bluntly.

"When Shuyi's men surrounded them, two had bitten poison sacs hidden in their teeth; Shuyi's men removed their jaws first, extracting the poison sacs together with two molars."

His voice dropped another half tone.

"The third ran half a li before a Hidden Agent shot his calf from behind; the man has already been brought back."

Chen Yan released his grip on the hilt.

"Did you pry open his mouth?"

The curve at Gao Jiong's mouth stretched a little longer.

"No need to pry; Shuyi placed the interrogated fellow before them. The one with the shot calf stepped forward first, saying they were only a forward post and that another group was already on the way."

Chen Yan kept walking without stopping, heading toward Zongguan Fu, his voice drifting back on the night wind.

"How many?"

Gao Jiong followed behind, the clatter of Armor echoing across the open street.

"Over ten people, all dedicated Suicide Warriors of Qi State's Shadow Division, carrying Blazing Oil, their target being the Workshop."

Chen Yan stopped at the Damen of Zongguan Fu and turned back.

Moonlight illuminated his face, and the thing swirling in those eyes sent a fine, dense chill down Gao Jiong's spine.

"Let Red Leaf stay in the Workshop tonight."

He pushed open the Damen of Zongguan Fu, and his voice crossed the threshold, drifting into the courtyard.

"Withdraw all the patrolling Bright Guards, replace the Hidden Agents with Beiwei Dead Guards; within fifty steps of the Workshop, not even a fly may enter."

Gao Jiong struck the Chest Armor with a fist.

"Shuyi, I'll arrange this right away."

Chen Yan walked into the courtyard gate, and the night wind lifted a corner of his robe, revealing the sheath of his side sword at his waist.

The hammering in the Workshop continued, each strike like a nail driving into the bone crevices of Xiazhou's parched land.

And in the dark depths beyond the reach of those hammer sounds, more than ten pairs of cold eyes were closing in on this direction.