"I am not tired." Zhang Yu'er walked obediently behind the emperor and stretched out her hand to massage his shoulders.

Zhu Youxiao gently patted the little girl's hand, leaned back in a more relaxed position, and said to Liu Ruoyu with his eyes half open and half closed, "I will dictate, and you write it down!"

Liu Ruoyu responded, spread out the paper, picked up the pen, and listened attentively.

Zhu Youxiao pondered for a moment, then spoke slowly, "Replying to Lord Xu: As the "Divine Artifacts Catalogue" states, charcoal fire is the best for iron smelting. Charcoal is expensive in the north, so we have to use coal fire instead, which is why there are so many explosions. I've thought about using coke as an experiment..."

Coal contains harmful elements such as sulfur and phosphorus. If it is used directly to make steel and iron, it will definitely affect the quality and the performance of the guns and artillery produced.

Zhu Youxiao understood this point.

But what he didn't understand was: According to research, there was evidence of the use of coke in the Song Dynasty, but why did no one understand it in the Ming Dynasty?

The swords made during the Han and Tang dynasties were among the best in the world. How come they were surpassed by the Japanese during the Ming Dynasty?

Zhu Youxiao carefully considered his words while speaking, and could not say anything too profound.

What determines whether something is iron or steel, or whether it is soft or hard, based on its carbon content? With the eagerness of Xu Guangqi, Sun Yuanhua, and others to learn, wouldn't they have to confuse themselves to death?

Besides, it is hard to explain why an emperor in the deep palace like me understands all this!

Well, I have to write a book, saying that it was my accidental discovery that made the technology of the Ming Dynasty leap forward and surpass the Red Barbarians and Western Barbarians.

Zhu Youxiao touched his stomach and felt that there was so much knowledge here that it seemed like it was about to burst out.

………………