Although Emperor Tianyou had convicted Feng Wenlan and Kong Zhou of treason, their relatives and associates were detained for separate trials. This was still considering the feelings of the princes and great ministers at court, with no intention of exterminating the entire Feng clan.

Collateral branches of the Feng family and even Feng Wenlan’s concubine-born sons might receive relatively light punishment. However, as legitimate sons of Feng and Kong, Feng Liao, Feng Yi, and Kong Xirong would likely still find it difficult to escape severe punishment.

Even without fabricating additional charges against them, they would probably at minimum face military exile or be reduced to official slaves.

Han Qian wasn’t surprised that Feng Liao, Feng Yi, and Kong Xirong had escaped from Jinling. But he thought, with the world so vast, where could they flee to?

Perhaps they had never imagined that one day they would fall to such a state.

However, after the Feng family had gone to such trouble to retrieve Feng Yi and Kong Xirong from Lanting Lane, Han Qian didn’t want to concern himself with this matter. When Tian Cheng came to mention it, he just listened. Looking up at the azure cloudless evening sky, he sighed about the crisp autumn air and fine cool autumn weather, then mounted his horse. Escorted by Zhao Wuji, Xi Fa’er and others, he rode toward East Hua Gate in the sunset.

By the time he returned to the estate, the sky had already darkened. After eating, Han Qian ran to the forge to watch Chen Jitang lead the craftsmen in studying refined steel casting methods.

After over half a month of trial furnace operations, the benefits of the new semi-enclosed chamber furnace were gradually being explored further.

From Chen Jitang and the others’ practice, Han Qian also confirmed that the melting point of refined steel was actually much higher than that of pig iron. With the semi-enclosed chamber furnaces currently built by the forge, pig iron blocks would quickly melt into molten iron, but an excellent straight-spine knife could only be heated to redness suitable for further hammering after burning for half a day.

This was also the key reason why hundred-refined steel became increasingly difficult to forge in later stages.

Even Chen Jitang didn’t understand why this was so, but for Han Qian, some of the knowledge from his dream visions, which had been vague and unclear in places, now became suddenly clear.

This was obviously because differences in carbon content and impurity levels determined the different melting points of steel and iron.

If one didn’t want to spend years forging laboriously to obtain good steel, the key to saving more effort and trouble was actually to continue finding ways to increase furnace temperature.

Especially with extremely high furnace temperatures, when pig iron was smelted into molten iron, with appropriate stirring while continuing to blow in air, the carbon content could be directly reduced without needing to hammer out the carbon. This could produce true wrought iron, which was the “soft iron” referred to in the saying “how can hundred-refined steel turn into softness that winds around fingers.”

However, for weapons and armor plates, lower carbon content wasn’t necessarily better. Removing impurities, decarburizing, or even conversely adding carbon—there was far too much to explore here.

Every day, cartloads of charcoal and pig iron were transported into the forge, consuming thousands or even tens of thousands of qian, yet they couldn’t produce a single serviceable fine blade. Chen Jitang and many master craftsmen were anxious. But Han Qian consistently emphasized that he should be patient, cast aside old conventions and bad customs, and explore and summarize bit by bit.

Han Qian was also devoting a large portion of his energy to this. Whenever he was at the estate, he spent most of his time at the forge, his skin reddened from the scorching heat.

These past two days, Chen Jitang and the others had tried using cheaper coal briquettes to replace expensive charcoal, but found that the refined steel produced shed more iron slag when hammered.

Han Qian speculated this might be because coal briquettes contained other impurities that entered the molten iron or steel bars during smelting, making them brittle, manifesting as increased iron slag during hammering.

Today Han Qian specifically had Chen Jitang conduct controlled experiments with charcoal and coal briquettes. When he called him to the forge, Chen Jitang told him they had indeed verified that crude steel smelted with coal briquettes broke more easily.

“Steel refined with coal briquettes might work for making farm tools, but for making swords and armor, it won’t do,” Chen Jitang said. Now overseeing craftwork and manufacturing at the estate, he had gained confidence and spoke more decisively.

Pig iron couldn’t be used because its high impurity and carbon content made it brittle. Steel refined with coal briquettes showed little improvement in properties. It could work for casting farm tools, but what Han Qian ambitiously wanted was to mass-produce cheap, high-quality refined steel armor plates or refined steel components.

For small-scale steel forging, charcoal consumption wasn’t particularly extravagant, but for large-scale iron smelting and steel refining, coal briquettes had too great a cost advantage.

Moreover, producing charcoal consumed large amounts of timber. This was no longer just a question of environmental protection or ecology, but a major issue of how long the few remaining forests near Jinling city could withstand such consumption.

Han Qian squatted in the corner of the forge courtyard, weighing a coal briquette in one hand and a piece of charcoal in the other.

The person in his dream, Zhai Xinping, hadn’t studied engineering. Having Han Qian figure out what impurities were in these coal briquettes and how to remove them was really asking too much of him.

At this moment, Xi Ren led Xi Fa’er over, called Han Qian aside, and said, “Someone claiming to be a Feng family retainer came to the estate at night looking for Guo Que’er, saying he has something he wants to see Your Excellency about.”

Xi Fa’er and his father Xi Chang were among the few Xi clan members with close blood ties to Xi Ren. Xi Chang and Xi Ren’s mother, Gao Xi Shi, were even cousins.

After Xi Chang and Xi Fa’er were redeemed, Han Qian initially had them command and train slave soldiers, then serve as deputy commanders of Xuzhou Battalion.

After the Xichuan campaign, most of the convict soldiers returned to Xuzhou. A small number of convict soldiers were recruited as armed guards for the boat gang, and Xi Chang also directly joined the boat gang with Feng Xuan to work with Yang Qin. However, Xi Fa’er, who was two years older than Zhao Wuji, led a group of Xi clan youths who practiced stealth and concealment arts and remained as private soldiers for Han Qian’s use.

Feng family retainers were now either detained in the Court of Judicial Review’s prison awaiting trial or had already fled Jinling. For someone to suddenly claim to be a Feng family retainer coming late at night, Han Qian’s brows also furrowed slightly.

“Perhaps Feng Yi has come to ask Your Excellency for rescue?” Xi Ren guessed.

“What could I possibly save him from?” Han Qian rubbed his temples to ease the throbbing pain, then said to Xi Fa’er, “Where is the person? Has anyone else seen him?”

“This person is quite capable. He managed to enter the estate and find Guo Que’er without our men noticing,” Xi Fa’er said somewhat ashamed. He was responsible for guarding the estate tonight, and having someone slip in silently made him very uncomfortable.

Counting the days, Yang Qin and Xi Chang were leading the fleet from Xuzhou. Lin Zongying and Guo Nu’er had taken some men ahead by boat to purchase silk in Runzhou.

Han Qian couldn’t divert Left Division scouts and spies for private use at the estate. With only the dozen or so guards led by Zhao Wuji and Xi Fa’er, it was impossible to guard an estate currently housing nearly three hundred people without any gaps.

Although everyone in the estate was part of the Han family’s retainers and servants, they still had to guard against loose tongues. Not wanting to alarm too many people, Han Qian had Xi Ren and Xi Fa’er lead the way to where Guo Que’er was recovering from his injuries.

Both of Guo Que’er’s parents had died of severe epidemic disease shortly after being recruited into the garrison military office. Guo Que’er had roughly learned martial arts and was clever. He had been selected into the Left Division early on and directly assigned to work at the Feng residence.

After Feng Yi and Kong Xirong were retrieved from Lanting Lane, they ultimately revealed some secrets they knew—afterward, besides telling Yin Peng about Chun Shisanniang’s whereabouts, Feng Wenlan had also imprisoned and severely tortured Guo Que’er, wanting to learn more secrets about the Commandery Prince’s mansion and the Left Division as capital for self-preservation.

Only after Feng Wenlan and Kong Zhou were confined in the palace by Emperor Tianyou did the Feng family send back the tortured and disfigured Guo Que’er. These past few days, Guo Que’er had been recovering from his injuries at the Yandang Cliff estate.

Guo Que’er had been taking a walk by the pond at night when the Feng family retainer found him. He also knew this was no small matter and brought the person to the compound where the guards lived to report to Xi Fa’er.

Walking into the room, Han Qian saw a thin, stubbled man standing anxiously by the window. When he pushed the door open, the thin man was startled—clearly he’d received quite a few frights these past days.

“This humble one is Li Qilü. Does Han Daren remember?” The thin man, seeing Xi Ren, Xi Fa’er and others standing vigilantly behind Han Qian, didn’t rashly approach but stood by the window, bowing in greeting.

This thin man was a guard that Feng Wenlan had later assigned to Feng Yi’s side to restrict Feng Yi’s movements. Since he only followed Feng Wenlan’s orders, Han Qian had seen him several times but hadn’t spoken with him much.

“You have such audacity! The Feng family committed heinous crimes. That their entire clan wasn’t exterminated is already His Majesty’s magnanimity and benevolence. Instead of reflecting on your faults and redeeming your sins, you dare to flee the city. Do you truly think you can escape the dragnet His Majesty has spread? Someone! Seize this dog slave and torture him! Even if we have to beat the shit and piss out of him tonight, we must extract the whereabouts of the criminals Feng Yi, Feng Liao, and Kong Xirong!” Han Qian had no intention of reminiscing with the visitor. After staring at the thin man for a moment, he directly ordered his detention.

Xi Fa’er and the others surged into the room like tigers and wolves, grabbing the thin man and pressing him down into the muddy ground.

“Han Daren! Han Daren! We know the Feng family committed heinous crimes, embezzling and perverting justice, and truly deserve death. We’ve already detained Feng Liao and his brothers and are waiting to hand them over to Han Daren, so Your Excellency can send them to the Court of Judicial Review for trial!” The thin man hadn’t expected Han Qian to have him pressed into the damp mud without a word of discussion. He hurriedly shouted.

Xi Ren looked at Han Qian in surprise, truly unable to understand how he knew this person hadn’t been sent by Feng Yi to seek help, but had come to claim a reward for capturing Feng Yi, Feng Liao and the others.

“Oh,” Han Qian stared suspiciously at the thin man and said, “If you can show great righteousness and assist the authorities in capturing the criminals, it would indeed be atoning for crimes through merit. Perhaps the ministries will even have generous rewards for you…”