Artillery technology, like rifles, has a long process of progress.

So far, the West, represented by grapes, is still in the stage of copper cannons.

But there are already signs of studying iron cannons.

The Ming Dynasty was in the technical stage of copper and iron tires, but there was no way to go further.

Craftsman artillery is a felony as long as it is blown up, and everyone will be afraid.

So he went headlong into the astray path of casting "Divine Fire Flying Crow" and so on, prevaricating.

If you follow the historical trajectory, the honor of being the first to make an iron cannon should belong to Huang Taiji.

With his painstaking funding, under the leadership of craftsmen led by Wang Tianxiang and Jin Shixiang, he finally succeeded in casting a Hongyi cannon with the "lost wax method" in the fifth year of Tiancong (1631).

Huang Taiji was overjoyed, and immediately named Wang Tianxiang as the general manager of Qian, and named the cast Hongyi cannon - Tianyu Cheering General.

However, now this honor is probably owned by Yang Chengying.

Yang Chengying actually didn't understand the Hongyi cannon at first.

In fact, he initially regarded more than a dozen Hongyi cannons as made of iron, and he was still thinking about how to use reverse engineering to create Hongyi cannons.

Later, it was Sun Yuanhua who told him that these cannons were cast in copper.

Sun Yuanhua also said that maybe because of the long time, he can't see it from the outside.

Of course, this is Sun Yuanhua's innocuous lie to save Yang Chengying's face.

Yang Chengying also knew, but it wasn't broken.

"Unexpectedly, Mr. is so attentive that he has already designed the drawings."

Seeing the design drawings of the iron-cast artillery, Yang Chengying was overjoyed.

Sun Yuanhua said with a smile: "Since the general mentioned this matter, I have been thinking about this matter. I also took the time to do some small experiments, and also exchanged letters with Mr. Mao.

In the end, we came to the conclusion that if we used the 'lost wax method', we might be able to forge the iron cannon that the general wanted. ”

The lost-wax method is a precision casting process with little or no cutting.

There are advantages such as high accuracy, but there are also disadvantages that are affected by the season.

"Okay, when it comes to winter, we will cast artillery from iron!"

Yang Chengying said happily.

"This is just my initial idea, and it has not been tested in practice, so I don't know if it will work out in the end." Sun Yuanhua said modestly.

"It doesn't matter. Anyway, what I have is the raw materials, and if I don't think it's enough at that time, I'll find a way. ”

Such a big killer, still worried about money?

Of course, it is not a matter of blood.

Yang Chengying also wants to put it on the ship in the future to deal with the West such as Grape and Tooth, or to go to the Japanese country.

Protect the "trade" at sea, by the way, shout "open the door, send trade".

The money doesn't just roll in.

After reading the drawings, Yang Chengying and Sun Yuanhua came to his precious artillery unit.

After the lesson of the last time, Yang Chengying carried out a round of personnel replacement in the artillery unit.

Change to an old with a few new configurations and learn artillery shooting techniques.

Newcomers have little battlefield experience, but they are young and can quickly adopt new technologies.

This is coupled with literacy activities.

These artillerymen finally have a little bit of meaning.

But it doesn't stop there.

However, Yang Chengying did not show it in person.

Sun Yuanhua saw it.

When he walked farther, Sun Yuanhua asked with a smile: "The general doesn't seem to be very satisfied with this artillery unit?" ”

"It's already good."

Yang Chengying was afraid that he would misunderstand, so he hurriedly added: "Really, it's good." ”

"Then, why is the general still sullen?" Sun Yuanhua asked curiously.

"It's too rough!"

When he said this, Yang Chengying was also a little anxious.

Although he was a top student in the military academy in his previous life, he did not study artillery.

Not much is known about ancient artillery either.

"General, the artillery shooting in my mind is a hundred shots."

Sun Yuanhua shook his head with a smile and said, "That's impossible. I can't even do what I've learned, let alone them. ”

"That's right."

Yang Chengying smiled bitterly.

As he walked, Yang Chengying saw the cross hanging by Sun Yuanhua, and his eyes suddenly lit up.

Sun Yuanhua had studied geometry from his teacher, and he must have learned much better mathematics than at that time.

Why don't you teach Sun Yuanhua about mathematics, such as parabolic equations?

Thinking of this, if you want to go one step further, it is better to compile a set of math textbooks.

Start with the most basic math.

"Mr. Sun, have you ever learned Geometry from your teacher?"

Yang Chengying suddenly asked.

Geometry originals, the book consists of thirteen volumes.

Based on the twenty-three definitions, five axioms and five axioms of the first volume, 119 definitions and 465 propositions and proofs are given.

It includes some content of plane geometry, solid geometry, and elementary number theory.

Xu Guangqi and Matteo Ricci jointly translated the Geometric Originals in the 35th year of Wanli (1607).

After such a long time, Xu Guangqi may have taught Sun Yuanhua.

Sun Yuanhua was stunned and said in surprise: "I have learned, the general knows the original geometry so well!" ”

In his opinion, how could a person from a military household know the original geometry.

"I naturally have a way of knowing."

Yang Chengying said with a smile: "Since you have studied the original geometry, you should be able to understand the math textbook I wrote." ”

"Numbers, math textbooks!" Sun Yuanhua was already stunned.

"You give me a copy of the original geometry, and I will write a set of math textbooks on the basis of it."

Yang Chengying said: "You and Mr. Mao learn first, and then I will find some people with good academic performance to learn from you."

With these foundations, I think there has been a significant improvement in both cannon casting and artillery shooting skills. ”

However, Sun Yuanhua did not react at all.

He was still in shock.

You must know that his teacher Xu Guangqi took a lot of effort to translate the original geometry with Matteo Ricci.

His teacher was also very emotional at one time, except for a few people, no one can be willing to learn, and they can't learn.

Unexpectedly, a general from a military household in front of him would actually write a mathematics textbook on the basis of the original geometry.

"Mr. Sun, are you listening to me?"

Yang Chengying stretched out his hand and shook it in front of Sun Yuanhua's eyes.

Forehead!

Sun Yuanhua came back to his senses and asked excitedly, "General, oh no, Mr. Yang, do you really want to do this?" ”

"Of course, I'm going to start with the basics. Write a set of math books that start with the basics of math and work your way up step by step. ”

Yang Chengying said indifferently.

Sun Yuanhua stroked his heart and felt a little difficult to breathe.

"Well, Geometry wasn't with me originally. I, I'll write to the teacher and send you a copy of the original geometry. ”

Sun Yuanhua still didn't slow down, and his speech was still stammering.

"Okay." Yang Chengying nodded, "By the way, I'm going to transfer Shang Kexi and the firearms unit over and teach them mathematics." ”

Historically, Shang Kexi learned a fluent Grape Language under Sun Yuanhua, and he is also a talent who is good at learning.

Thinking of this, Yang Chengying suddenly realized that the "King of Sanshun" was actually under his command.

What a wonderful fate.