Great Song Dynasty Writer

Chapter 128 A True God!
However, this place is indeed far enough away from the Tuojiang and Yangtze Rivers that conducting experiments here will not pose any danger of water backflow causing flooding of the city.

As for why this place was chosen as the experimental site, but the floodwater wasn't drained out from here.

The reason is simple: because of its high elevation, most of the floodwater from the city doesn't reach here; only some of the floodwater from the north of the city can flow down this old ditch.

"This is it!"

Lu Beigu squatted down and carefully measured the dimensions of the culvert, estimating the pressure and potential impact of the water flow.

Soon, Liu San arrived with several panting craftsmen, braving the rain.

The elderly carpenter at the head of the group was over fifty years old, his hands covered in calluses. They were taking shelter from the rain in the city gate archway. He looked at the blueprints, then at the culvert not far away, his brow furrowed: "Scholar Lu, can this wooden door really open and close by itself when it's soaked in water? Won't it be washed away by the water? Won't it get stuck in the silt?"

Lu Beigu stood up, raindrops dripping down his chin, but his eyes were sharp as knives: "Trust me and do it according to the drawings! I've already measured the dimensions. Use the hardest camphor wood scraps, and make sure the iron shaft is thick and sturdy!"

His voice wasn't loud, but it carried an extremely strong sense of confidence, which made the craftsmen, who were originally full of doubts, feel a chill.

Seeing the young scholar's disheveled appearance, soaked to the bone by the rain, and the burning urgency in his eyes, the old carpenter wiped the rain off his face roughly: "Alright! I've been a carpenter all my life, and I've never seen such a rare thing before! We'll do it your way! Brothers, get the tools!"

"You two go clear the mud from the cave entrance! The rest of you, follow me and start feeding!"

At the old carpenter's shout, the craftsmen immediately sprang into action.

The sounds of sawing wood, chiseling stone, and shouting, all emanating from the base of the city wall amidst the raging wind and rain, somehow conveyed a sense of tragic grandeur.

Lu Beigu also rolled up his sleeves and personally participated in the process, explaining the construction of key nodes.

If this simple "water window" can work properly to drain the floodwaters from the city and keep the raging floodwaters outside the city, it can buy a little breathing room for Luchuan City, which is on the verge of collapse!
He must win this battle!

The rain poured down relentlessly, showing no signs of abating.

At the foot of the city wall, turbid water swirls in the old ditch, crashing against the culvert openings that have just been cleared.

Master Wang, the old carpenter, truly lived up to his reputation as one of the best in the city. His calloused hands flew across the wet wood, his chisel precisely biting into the camphor wood, producing a dull yet rapid tapping sound.

Two younger carpenters pushed and pulled the large saw with all their might, the hard camphor wood struggling to separate under the saw teeth, wood chips flying everywhere mixed with rainwater.

Old Li, the stonemason, and his apprentice were carefully cleaning and polishing the stone trough at the culvert entrance with steel chisels and hammers, preparing for the base of the water window.

The icy rain streamed down the edges of their raincoats, soaking everyone to the bone and turning their lips blue with cold, yet no one stopped.

"Student Lu, is the position of this iron axle correct?"

The old carpenter picked up a thick iron bar and gestured to the position of the water window pivot on the blueprint.

"Exactly!" Lu Beigu wiped the rain off his face and leaned closer to give careful instructions. "This is the most crucial part. The shaft hole needs to be perfectly rounded, and the gap between it and the iron shaft must be just right. It can't be too tight and jam, nor too loose and it will leak! The thickness and weight of the wooden gate also need to be strictly according to my calculations. If it's too light, it won't be able to withstand the water pressure, and if it's too heavy, the water inside the city won't be easy to push it open!"

"I understand, old man!"

The old carpenter's eyes were focused, and his hands were perfectly controlled, as if he were not creating a strange and unusual object he had never seen before, but completing the most proud work of his life.

Time passed amidst the sounds of sawing, wind and rain, and heavy breathing, each moment seeming exceptionally long.

Finally, a rectangular gate made of thick camphor wood, fitted with a sturdy iron axle, was lifted to the culvert entrance with the combined efforts of everyone. The inside of the gate, the side facing the city, was flat, while the outside was made into a slightly sloping surface according to Lu Beigu's drawings.

The corresponding stone troughs have also been cleaned and polished, fitting together perfectly.

Lu Beigu's voice was hoarse: "Place the gate into the stone trough and align it with the iron shaft hole! Be quick and steady!"

Several craftsmen gritted their teeth, shouted in unison, and worked together to lift the heavy wooden gate and carefully embed it into the cold stone trough.

The iron shaft passed through the pre-drilled hole, producing a dull rubbing sound.

Once installed, the wooden gate, relying on its own weight and a slight tilt angle, closed naturally, completely blocking the culvert outlet.

All eyes were fixed on the newly installed wooden gate.

Because the water level inside the city was higher than outside the city at this time, the inside of the sluice gate was under water pressure.

As the water surged, the heavy wooden gate remained motionless at first, but then with a muffled "whoosh," it was suddenly forced open by the immense pressure of the floodwaters inside the city!

The murky water, like a ferocious beast released from its dam, surged out of the culvert and rushed into the low-lying area outside the city! The enormous force of the water flow made the entire culvert seem to vibrate!
"It's done?" Liu San, the clerk, asked in a trembling voice filled with disbelief and hope. "It wasn't washed away by the outside water, and it didn't leak?"

"It's not over yet! The key is when the water rises outside the city!"

Lu Beigu's heart was in his throat. He knew the real test was preventing backflow.

As if to prove his words, the water level in the low-lying area outside the city, under the continuous influx of torrential rain and the pouring water from inside the city, finally exceeded the height of the culvert outlet! Muddy water began to flow back into the culvert!

The moment the murky water touched the sloping surface outside the sluice gate—

"It moved! It moved!" a sharp-eyed apprentice exclaimed!

The wooden sluice gate, which had been open, began to tighten slightly inward under the pressure of the water outside the city. Then it tightened even more!
The tiny gaps that might have leaked were completely sealed off by the sudden increase in water pressure!
The wooden gate was held firmly against the stone trough as if by an invisible hand, and no matter how much the surging water outside the city rushed in, not a single drop of water could seep into the culvert!

It really did shut itself off completely! And it shut itself off perfectly!

"Amazing! Absolutely amazing!"

The old carpenter's eyes widened, and his beard trembled with excitement. He rushed to the edge of the culvert, ignoring the mud and water, and reached out to touch the edge of the tightly closed gate.

"Seamless! Seamless! The water outside has sealed the sluice gate shut! Professor Lu, what you've done..."

Lu Beigu muttered to himself, "When the water recedes, open the window; when the water rises, close the window!"

"Quickly! Report to the prefect and the judge! The water window prototype is complete! The effect is perfect!"

The clerk, Liu San, reacted very quickly, his voice changing with excitement.

Lu Beigu looked at the surging water, then at the wooden sluice gate that trembled slightly and automatically adjusted its opening and closing angle as the water level outside the city changed slightly after everyone withdrew their strength, and let out a long, long sigh of relief.

(End of this chapter)