"There's one more thing you go back to make people think." Yun Xi said again: "Why can the boat float on the water." ”

"Your Majesty, the minister thinks that because wood can float on the water, a boat made of wood can float on the water." Zhou Wei said.

"Then why does wood float on the water?" Yun Xi asked again.

The three of them didn't know how to answer, and said in unison, "Please make it clear to Your Majesty." ”

"I don't know. So I need you to go back and study it. Yun Xi felt very uncomfortable in his heart: Ancient Greece had discovered the law of buoyancy by Archimedes more than 1,600 years ago, but the people of the Ming Dynasty still didn't know about it.

"In addition, I have a few questions for you to study." Since they now have to make up classes in all aspects, it is not easy to make a breakthrough in astronomy, so it is better to let them study more physics and mathematics. What's more, all aspects of science are interconnected, maybe the East is not bright and the West is bright, and they have obtained astronomical inspiration by touching on the bypass.

"You also have to calculate how many times the surface area of the sphere is the area of its maximum inscribed circle, how much is the volume of the cylinder inscribed sphere of equal length and width as the volume of the cylinder, and the relationship between the weight of the object placed on both sides of the lever and the length of the lever when it is balanced, and calculate the ,...... pi" Yun Xi asked five or six questions in a row.

Yang Shiqi and the others didn't know why Yun Xi asked them to study these questions and ask questions, but Yun Xi only said 'very useful', and they could only ask a few words they didn't understand, such as 'inscribed sphere', 'inscribed circle', etc.—and bowed down to agree after understanding.

After ordering all this, Yun Xixuan called Ai Su to his side and said to Yang Shiqi, Zhou Wei and others: "Since you have entered the palace, I happen to have another thing to tell you, so I will say it by the way." Gezhiyuan is still using calculations, right? ”

"Yes, Your Majesty." Yang Shiqi replied.

"Do you know Indian numbers?"

Zhou Wei shook his head, but Yang Shiqi and Cao Zheng both bowed down and replied, "The minister knows." ”

"That's fine." Yun Xi smiled: "Indian numerals, plus +、-、 = these symbols, are very convenient for arithmetic, much more convenient than arithmetic." ”

"What's more, the calculation plan is fiddled with wooden sticks, and the calculation process cannot be retained, while Indian numerals can be written on paper and counted, and the calculation process can be retained, which is another better place than the calculation chip."

"In the future, all the people in the Gezhi Monastery will use Indian numerals and Indian symbols to calculate the calculation problems on paper, and if they have studied a problem that I have instructed, they must use a brush or a pencil to write down the calculation process on paper and keep it for a long time." From a research point of view, the method of solving a problem is more important than the conclusion of solving the problem. You don't see, after the collapse of Lao Maozi in history, China pulled all kinds of design drawings from Lao Maozi's territory one train after another, even if the design proved wrong in the end.

"When there are more things researched by the Gezhi Academy, I will make them all together into a book, bind and publish them, and whoever studies which theorem, I will order his name to be written down in the book, and it will be passed on for eternity!" Yun Xi said.

"Thank you, Your Majesty." Zhou Wei and Cao Zheng said very excitedly.

What people in this world want, of course, is first of all to be fed and clothed, but isn't the pursuit of a higher level after being fed and clothed is to be famous before and after death? Now that Yunxi wants to give them this reputation, their great name will be passed down from generation to generation like Zu Chongzhi, how can they not be excited? Not only them, but even Yang Shiqi was moved and wanted to really devote himself to Gezhi research; Ai Su, who was standing on the side, had straight eyes and a look of envy on his face.

"Ai Aiqing, in the past few days, I have sent you to Gezhi Yuan to help them use Indian numerals, if you want, you can also study the problems I just said." Yun Xi smiled at Ai Su again.

"Thank you, Your Majesty." Ai Su immediately knelt down with great joy and said. He was happy because he was able to go to Gezhi Hospital, and the other was because Yun Xi called him Aiqing, which was a rare honor for an official of his rank.

After they regained their composure, Yun Xi said to Cao Zheng again: "You are now mourning for the old Huaiyuan Marquis, and I also know that you are sad for your father in your heart, so you can rest well at home, and then come back after the mourning period." ”

He said to Zhou Wei again: "You are now in charge of the Gezhi Academy, and I know that your favorite is astronomy, but if there has been no progress, it is better to study the problems I just mentioned." Unlike astronomy, these can be studied with simple objects in hand, and you don't have to use very large things. You can do as much research as you can when you are on duty in the Ministry of Engineering. "Since Zhao Haode, the secretary of the Ministry of Industry, knew Yunxi's intention of sending Zhou Wei to the Ministry of Industry, of course he would not send him too many errands, so Zhou Wei was very idle on weekdays.

"Yes, Your Majesty." Zhou Wei understood that the emperor was taking care of himself, and immediately agreed.

Yun Xi said a few more words and told them to step down.

Then he stretched his waist and said to Huang Lu, "Xuanqi Tai is here." No, I'm going to see him. "After all, Qi Tai is his cronie, or former cronie, so it's better to keep some decency. He then stood up again and walked to the side hall.

……

……

Qi Tai stood in the hall, pacing restlessly. He didn't know why Yun Xi called him over, and Huang Lu, who came to pass on Yun Xi's message, didn't dare to elaborate, but only hinted that what he did made the emperor unhappy, so he stood in the palace at this time and thought about what he did to make Yun Xi unhappy.

'Is it that the grain prepared for the Northwest has not been fully disbursed at the appointed time?' However, at that time, the food in Henan and Shanxi was not enough, and it took the expenses on the road to be allocated from other places. ’

'Is it His Royal Highness the King of Liao who asked for food but didn't give it? However, according to the regulations, the vassal king could not give money or food without His Majesty's permission. ’

'Is it not the full promotion of Indian numbers according to the emperor's wishes?' It was my negligence, but it was not a big deal, so as not to make Your Majesty so angry, that he had to call me from the household. ’

Qi Tai, who had thought about it for a long time and didn't come up with a result, patted his head depressedly. Since Jianye has been in contact with the emperor for three years, there has been less and less contact with the emperor, and even the emperor can't guess what he thinks, which is not possible. Take advantage of this opportunity to communicate with the emperor more after admitting your mistakes. Although Qi Tai is an upright minister, he will not be as rigid as Hai Rui.

As he was thinking, a voice came from the door: "Your Majesty has arrived!" He hurriedly straightened his clothes and stood still facing the door.