Prince Li You of the Great Tang Dynasty begs the noble families to their deaths!

The problem was that the assassins never managed to discover the Zhou family's method of building earthen kilns.

After all, it's someone else's cooking skill that they make a living from, and they keep it very well hidden.

Therefore, Li You decided to conduct some experiments to see if he could improve the quality of charcoal produced in the earthen kiln on his own.

If the experiment fails, then the only option is to have Master Zhou come up the mountain to personally guide the work.

"Da Shun, how long does it take to burn charcoal in the earthen kiln you built yourself?"

"It needs to be simmered for a day, then the fire opening is sealed, and after three to five days, the entire kiln is sealed. After another three to five days, the top of the earthen kiln is broken open, and the charcoal inside can be retrieved."

"Three to five days? There's no fixed timeframe!"

"My lord, we just burned them randomly; there really weren't any rules."

Li You nodded. No wonder the charcoal they burned was of poor quality; they hadn't refined it to any standard.

"When you sold firewood to Zhou Shengyi, did he specify which types of wood he would accept and which types he wouldn't?"

"No, they don't. As long as it's firewood, the Zhou family will take it all. They're not picky."

Not picky?

It's possible that the Zhou family mastered the firing techniques for different types of wood, which is why they didn't discriminate based on the type.

Those who can turn a simple craft into a business must have some tricks up their sleeves.

"My lord, I just remembered something. When I was in Chang'an, I saw someone using bamboo charcoal, and the meat cooked with it was incredibly delicious."

The speaker was Yan Hongliang, a carnivore who could hardly live without meat.

"Bamboo? That's fine too. As long as it's a material containing carbon fiber, it should be able to burn."

Carbon fiber? No one around had heard of this term, but no one asked any further questions.

"Here's what we'll do: first build three earthen kilns, then fire cedar wood separately, but each kiln will be fired for a different time. The first kiln will be fired for six days, the second for eight days, and the third for ten days. After we open the kilns, we'll see how it goes."

Chinese fir is a type of fir tree that prefers a humid and warm environment and is one of the most common tree species in southern forests.

Following the plan, Liu Dashun and his men spent two days building three earthen kilns.

The shape of these earthen kilns reminded Li You of a scene from his previous life where he went to a farmhouse restaurant with friends to eat roasted whole lamb. The kiln used by that Northwest restaurant owner to roast lamb was based on a principle that was basically similar to the earthen kiln that Liu Dashun and his friends had built.

The timber was readily available; it was taken over, processed, chopped into blocks, and then stacked inside the kiln.

After sealing the kiln opening, leaving a ventilation opening at the top, you can start firing.

The burning process lasted only one day. Liu Dashun noticed that the color of the smoke had changed, so he directly ordered the soldiers of the wood-cutting unit to seal off all the ventilation openings and fire pits.

Five days later, the first kiln was broken open. About half of the firewood had completed the carbonization process, while the other half was not fully burned and could only be considered a semi-finished product. Moreover, the overall quality of the charcoal was not high.

Seven days later, the second kiln was broken open, and the situation was slightly better, with about 70% of the charcoal still usable.

Nine days later, the third kiln was broken open, and about 90% of the wood was carbonized, breaking easily with a snap, and the quality had also improved.

After this comparison, not only Li You, but everyone else understood that the secret to making charcoal is closely related to the overall calcination time.

Previously, Liu Dashun and his group fired kilns only for their own urgent needs, rushing to open the kilns within a few days, resulting in poor-quality charcoal. Zhou Shengyi, on the other hand, was motivated by profit, which is why he researched the process more thoroughly.

"Very good. Let's continue the experiment, still using cedar wood, and fire it for twelve, fifteen, and eighteen days respectively, and see the results. In addition, build thirty more earthen kilns for future use."

The wait was rather long.

Ultimately, the kiln that fired for fifteen days created a miracle.

The charcoal, though still retaining the original shape of the wood, is entirely black and very lightweight to hold.

"My lord, this...this is just as good as the charcoal from that official Zhou's house!" Liu Dashun said happily.

Li You nodded in satisfaction. The experiment was a success, and there was no need to earn money for Zhou Shengyi to go up the mountain to guide the work.

Zhou Shengyi: Thank you!

"Next, thirty earthen kilns were started simultaneously, and only cedar wood was used for firing."

"These three old kilns will be used as experimental kilns. Liu Dashun, you will personally supervise the testing of other types of wood, including bamboo!"

"promise!"

"My lord, with this skill, we can take over the Zhou family's business!" Yan Hongxin reminded him.

Li Youze said, "No, no, no, let's not try to steal the Zhou family's business yet. From now on, we will continue to chop firewood and sell it to the Zhou family. Let's not change anything."

Seeing that the people around him didn't understand, Li You patiently explained, "Our team is currently developing in the mountains, and the outside world has no idea that we exist. This is our biggest advantage. If we rashly make contact with people down the mountain, for example, by taking away the Zhou family's business, it will inevitably arouse suspicion, or even attract the attention of the government. It would be a loss."

"A rabbit doesn't eat the grass near its burrow. Since we're going to sell, we might as well sell further away, preferably somewhere without competition. You guys start by burning the charcoal, and we'll use the finished product first. Next spring, we'll find a good place to start selling, preferably directly to wealthy families, to make even more money."

Once the King of Qi said this, everyone understood.

Li You's intentions were twofold: first, to establish a secret development base; and second, to engage in monopolistic operations.

The assassins have discovered that Zhou Shengyi's charcoal business only supplies officials and wealthy people in the Guangzhou area; he cannot reach any more distant areas, making it essentially a small local enterprise.

Rather than competing with the Zhou family for profits and causing unnecessary trouble, it would be better to find our own way and establish a monopoly in other places.

Moreover, the surrounding mountains are rich in timber, which is very low-cost. Once production scales up and the production methods are appropriate, the output is well guaranteed.

That winter, the rebel army kept warm in thatched huts using charcoal they had made themselves.

Keep in mind that this was a luxury that only wealthy families could afford back then.

……

Chang'an, Daming Palace, late at night.

Emperor Li Shimin couldn't sleep at night, so he went to his desk and looked through the memorials.

The successive rebellions of two princes, especially the rebellion of the Crown Prince which was so close at hand, had a very significant impact on the emperor's mood.

He was somewhat reluctant to stay in the Taiji Hall, so he issued an edict to move to the Daming Palace in the northeast corner of Chang'an City.

Daming Palace was originally Li Yuan's residence, and was later converted into an imperial palace.

Li Shimin did not come to this place often.

But I've been feeling really annoyed lately, so I decided to go for a walk.

There's another point, which is a bit strange, but when resting in the Daming Palace, Li Er often dreamed of Li Yuan, and the father and son could even chat in their dreams.

When Li Yuan was alive, Li Shimin harbored some resentment towards him. Now that his old friends have passed away one after another, and his princes are not living up to his potential, Li Shimin has truly begun to miss his father.