Chapter 3

Inside the Western Courtyard.

Ma Shu was busy melting iron by the fire, occasionally glancing at the busy Qin Haidao, his heart full of shock and intense curiosity. He couldn't understand when Qin Haidao had learned to smelt iron, but he didn't dare to ask too many questions.

Qin Haidao didn't explain either. He made a long clay crucible that could be heated from below, with holes on both sides. He then called in a carpenter from the household to help him make two bellows, which were connected to the holes on both sides of the crucible. By blowing air into these holes, the oxygen supply increased, significantly improving the combustion effect.

Next, Qin Haidao mixed fine sand, clay, and water in a certain ratio to create a mold for the horse spear. The mold was divided into upper and lower parts, with the spearhead slightly elongated and a blood groove in the middle to facilitate slashing and thrusting. He also added patterns to the ends of the spear shaft to increase friction and make it easier to grip.

After the mold was almost dry, he combined the upper and lower parts, reinforced them, and set them upright. The iron was just melted, and he poured it into the mold through the holes. Once the iron cooled, a rough horse spear was formed, but it was still wrought iron, far from the required hardness and needed to be processed into steel.

Turning iron into steel involves increasing the carbon content. Too high, and it becomes cast iron; too low, and it remains wrought iron. The carbon content is generally between 0.022% and 12.11%, depending on the need. For tools, a higher carbon content is used, combined with quenching and tempering, to solve the brittleness issue and make the tool tough and sharp.

Qin Haidao asked Ma Shu and the others to leave. The next step involved technology that was beyond this era. If it were to leak out, the consequences could be severe, even triggering wars. Although Ma Shu was one of his own, human nature is unpredictable. Other techniques could be shared without much risk, but the method of steelmaking was too special and had significant implications, so it couldn't be disclosed.

He placed the horse spear in the long clay crucible, covered it with charcoal, fermented black beans, and soil powder, and heated it from below. He operated the bellows with both hands, making a whistling sound as the charcoal quickly heated up.

The charcoal and fermented black beans were used for carburization, while the soil powder acted as a dispersant. This method ensured that the horse spear received a uniform and stable carburization, with high carbon content, making the process efficient and effective. This technique is known as "muffling steel."

By late night, Qin Haidao opened the crucible, took out the horse spear, and lightly tapped it with his finger. It produced a clear, familiar steel sound. However, the process wasn't complete yet; it still needed tempering. There are three types of tempering: low-temperature, medium-temperature, and high-temperature. Qin Haidao chose low-temperature tempering, heating the horse spear to around 150-250°C, holding it for a period, and then cooling it in a cooling agent.

The cooling agent contained a certain ratio of salt and oil, which improved the physical hardness and, crucially, the wear resistance and elasticity.

With this step, the steel horse spear was complete. The remaining work was polishing and sharpening, which was time-consuming and labor-intensive. He could leave this to Ma Shu. Qin Haidao followed the same process to create a sword and a three-edged military dagger, engraving an abstract phoenix on the sword.

The phoenix was the totem of the Wang family. To deceive the Wang family, he had to give them some sweet incentives. He wasn't worried about the Wang family turning against him; the outcome of a battle depends on the person, not the weapon.

By the next morning, everything was complete.

Qin Haidao called Ma Shu over and instructed him to polish the sword and then rest. After working for a day and a night, Ma Shu was quite exhausted.

Initially, Ma Shu thought Qin Haidao was just playing around, as he had never made weapons before. When he saw the sword, he was amazed and extremely excited, wanting to call Qin Haidao to become his master but didn't dare to say it out loud. He started polishing the sword seriously.

After another day and night, Ma Shu finally finished polishing the sword. The blade was dark green, smooth as a mirror, and reflected light. The edge was razor-sharp, making one's heart race. Ma Shu's eyes were bloodshot from exhaustion, but he was very excited. He found a scabbard, put the sword in it, and hurried to the back courtyard gate, shouting excitedly, "He'er, He'er, is the young master awake?"

"It's Uncle Ma. The young master is already awake and practicing his halberd technique," He'er said, coming out from the back courtyard.

Ma Shu couldn't enter the back courtyard, so he presented the sword with both hands, saying excitedly, "Please deliver this sword to the young master."

"Leave it to me."

He'er took the sword and hurried into the back courtyard, arriving at the training area. She saw that Qin Haidao had just finished practicing and quickly approached, saying, "Young master, Uncle Ma asked me to deliver this sword to you."

"Polished? Let me see." Qin Haidao took the sword and drew it out. A cold air rushed to his face. He lightly tapped it, and it produced a sound like a dragon's roar or a tiger's growl. He picked up a nearby halberd and swung it at the sword.

"Clang—"

Sparks flew, and the halberd developed a notch, while the sword remained unscathed. He was completely reassured. The halberd represented the highest level of weapon smelting in the Tang Dynasty. If it could create a notch in the halberd, this sword was good enough to deceive the Wang family.

After changing into casual clothes and having a quick breakfast, Qin Haidao hurried out and went to a weapon shop. The shopkeeper recognized him and greeted him with a bow, "Greetings, young master of the Qin household."

Technically, Qin Haidao had inherited the title of Duke of Qinqu, so he could be called "Young Duke Qin," but the shopkeeper, from the Bole Cui family, though a branch and a commoner, still had the pride and superiority of a noble family and looked down on Qin Haidao, a descendant of a military family. Calling him "young master" was already a courtesy.

Qin Haidao said coldly, "I heard your weapons are the best in the world. Are you willing to compete?"

The shopkeeper, realizing he wasn't there to buy weapons but to challenge him, became even more unfriendly and asked coldly, "Many people come to compare weapons every day. How do you want to compete?"

"Since I'm here, I'll follow your rules."

"Very well. The bet is one thousand taels, with a written agreement and the government as a guarantor. Do you dare?"

"Quickly, I'm in a hurry." Qin Haidao pretended to be impatient.

Weapon competitions were common. If successful, the weapon's value would increase significantly. The Cui family, tired of constant challenges, had set a rule of a one-thousand-tael bet. The shopkeeper immediately sent a helper to call people.

The news of the weapon competition spread quickly, drawing a large crowd. Cheng Chumo, who was on patrol nearby, also heard the news and came over, asking with concern, "Brother Qin, I heard you were injured. I visited your house, but the steward said you were resting and couldn't see visitors. Are you okay?"

"I'm not fully recovered yet, thank you for your concern."

"Among brothers, there's no need for formalities. My brothers are investigating. If I find out who did this, I'll rip off their head," Cheng Chumo said fiercely.

Qin Haidao felt the sincerity and warmth of his friend's concern. Having such a friend was a good thing. After a brief chat, several officials hurried over, asked a few questions to confirm that both parties were willing and understood the rules, and wrote down the agreement. Both parties signed and sealed it, making the bet legal and binding. If anyone tried to back out, the government would intervene.

Cheng Chumo, familiar with Qin Haidao, knew that the best weapons in the Qin household were Qin Qiong's tiger-head spear and a pair of iron halberds. However, the Cui family's weapons were famous, and he was somewhat worried, asking, "Brother, are you sure you can do this?"

"Let's see after the competition," Qin Haidao said nonchalantly, looking at the shopkeeper and adding, "The agreement is signed; let's start."

"Fine, I'll send for the Crimson Blood Blade," the shopkeeper said coldly.

The crowd was in an uproar. The Crimson Blood Blade was extremely famous, said to be crafted by a master swordsmith, a descendant of Ou Yezi, over three years using a meteorite. It was the shop's prized possession, entirely red like blood, hence its name. It had never lost a competition, and someone had offered ten thousand taels to buy it.

Cheng Chumo, hearing about the Crimson Blood Blade, panicked and quickly grabbed Qin Haidao's arm, lowering his voice, "Brother, why don't I protect you and get you out of here? No one will dare to stop us."

"No need," Qin Haidao said calmly, pushing Cheng Chumo's hand away and stepping forward.

The onlookers whispered and pointed, with some saying disdainfully, "The Crimson Blood Blade is out, and this person is just asking for a loss. He's overconfident and arrogant."

"Exactly, this person must be desperate to prove his weapon. Why not find someone else to compete with? Choosing the Cui family is just asking for humiliation."

"The outcome is clear; there's nothing to see. Let's go, let's go."