After Li Zhi entered the academy, Daniu and several children took him with him.

After the school class was over, Li Zhi returned to the horse circle and pestered Li Zheng who was cooking, "Li Zheng, Brother Niu said that light can be refracted."

Li Zheng nodded slightly, "It can always be refracted."

Li Zhi asked again: "Then why is the scene reflected behind the small hole the opposite?"

While boiling fish soup, Li Zheng explained: "That is small hole imaging, and the other is light refraction, which are two problems."

Li Zhi continued, "Brother Big Niu is so awesome."

Li Zheng put a bowl of fish soup on the table, then cooked braised pork.

Daniu must have seen the course on Xiaokong imaging, which is indeed written in his own book.

Li Tai came back on mealtime. Every time he came back, Li Tai was sweating all over and was willing to sit down and eat after taking a shower.

After dinner, Li Zheng told Li Zhi about why Xiaokong imaging reversed.

A circle is drawn on a piece of paper to represent a small hole. Li Zheng drew a diagonal line and said, "Your Highness, the light is first illuminated by a straight line. If you want light to refract, you need a condition to allow optical refraction. So there is no refraction condition after the light imaging light passes through the small hole, or is it a straight line right?"

Li Zhi nodded in a daze, "I understand a little, the straight line and the straight line are in a different way."

Li Zheng drew a line again, running through the small hole from the footsteps of the portrait, slanting upwards, "So the portrait will turn upside down, the light does not encounter refraction conditions, so it is also straight in the small hole."

"I understand now." Li Zhi nodded.

Li Tai sat aside and asked, "So how can you refract light?"

"Mirror and water." Li Zhi immediately replied, "Brother Daniu told me."

Li Zheng pinched Li Zhi's fat face and said, "Your Highness King Jin has learned well."

That night, Li Zhi was already asleep. Seeing Li Zheng sitting by the horse circle and looking at the starry sky, he walked up to him and asked, "Can't you fall asleep?"

Li Zheng said with a melancholy look on his face: "Your Highness, when will your father pay me your salary?"

Li Tai really doesn't want to answer Li Zheng's question, and wondered when his father will give you Li Zheng's salary, how do I know? Are you, Li Zheng, so rich, still lacking those salary?

After coming to the cottage to relieve his work, Li Tai washed his face again.

Li Zheng often stares at the starry sky in a daze.

Li Tai has become accustomed to such things.

Li Tai sat beside Li Zheng and said, "Do you like star sighting at night?"

"Does Your Highness the King of Wei want to watch it together?"

Li Tai looked up at the stars in the night sky, "What do you think of such a star sign?"

Li Zheng shook the folding fan in his hand and said, "It means that the Tang Dynasty will flourish in the next hundred years."

"Is that so good."

It seems that Li Tai is very helpful to this sentence.

Li Zheng continued: "Your Highness, do you know? No matter how the world changes, the stars in the sky will not change for a long time. Look at the moon, it will accompany us for many, many years, thousands, or even ten thousand years."

The eternal starry sky? Li Tai looked at Li Zheng in surprise, "Li Zheng, are you comprehension about the great way of heaven and earth?"

Li Zheng smiled disdainfully, "If you can understand the great way of heaven and earth by looking at the night sky, astronomers all over the world should be able to become immortals."

"What is an astronomer?"

"His Royal Highness of Wei can be understood as one of the various schools of thought."

Li Tai looked suspicious, "Is there this one among the hundreds of schools of thought?"

"Maybe there is." Li Zheng nodded.

"Why hasn't I ever heard of it?"

"Because they are all very low-key." Li Zheng turned his head and looked at Li Tai, "Is Your Highness the King of Wei still going to sleep? I will go to the construction site to build roads tomorrow morning."

Seeing that Li Zheng was unwilling to say more, Li Tai went back to bed.

Li Zheng was still looking at the stars in the sky. The ancient night sky was very beautiful and very clean.

The horse in the horse circle snorted, and Li Tai and Da Hu snored from afar. Li Zheng was lying on the recliner and turned over to go to bed, and wanted to make the sofa out of the way.

When he got up the next day, Li Zheng felt that his bones were rebelling. This was the consequence of sleeping on a chair.

Seeing Li Zheng walking with his waist on his back, Dahu hurriedly said, "What's wrong with General Zhonglang?"

"Nothing." Li Zheng said to Dahu: "I just didn't sleep well last night, and I'll get much better after moving for a while. Have you been fed the horse?"

"It's already fed." Dahu said.

When Wang Ding came to Jingyang again, Li Zheng knew that Li Shimin could not wait.

"Eunuch Wang, please sit down quickly." Li Zheng said as he invited.

Wang Ding sighed, "Marquis of the County, County Marquis, there has been no news for three months, so this will make Your Majesty wait."

"Isn't this time yet?" Li Zheng said indifferently.

Wang Ding said: "There are ten days left."

"Ten days are heaven, it must be done." Li Zheng patted his chest and said, "It's not easy to make a triangular thorn if it's not a compound bow."

"Simple..." Wang Ding put down the teacup in his hand, "Since it is simple for the county marquis, why should I drag it again and again?"

Li Zheng added another cup of tea to Wang Ding and said, "Does Eunuch Wang think I am smart?"

Wang Ding nodded, "You are very smart."

"That's all." Li Zheng continued, "I wonder how much is the equivalent of Eunuch Wang, five plus seven plus eight plus nine plus ten..."

"Equally..." Wang Ding counted his fingers for a long time and couldn't speak.

"Equal to thirty-nine." Li Zheng said.

"So it's thirty-nine." Wang Ding replied, wiping the sweat on his forehead.

"I think some things are simple and Eunuch Wang think are simple are different. I think something is simple. Eunuch Wang definitely thinks it is not simple. Eunuch Wang thinks it is not simple. Eunuch Wang thinks it is not simple. Things that are not simple must be simple for me."

Wang Ding covered his forehead and said, "County Marquis, wait, the old slave is a little confused now."

Li Zheng continued: "Anyway, what I said is simple to make a triangular thorn, which is very difficult for Eunuch Wang."

"is that so?"

"So Eunuch Wang and Eunuch Wang please go back and report to His Majesty."

After Wang Ding returned, Li Zheng watched the old eunuch come to Jingyang again.

"Marquis of the County, Your Majesty said that our family will wait in Jingyang until the new weapon is born."

Looking at Wang Ding with compromise, Li Zheng sighed helplessly, "Your Majesty is really impatient."

Wang Ding said, "Your Majesty cares about new weapons very much."

The old eunuch's smile is indeed a bit cunning.

Wang Ding said calmly: "Marquis of the County, Your Majesty wants to hold the imperial examination, and now there are many difficulties. Is there any way to do this?"

Li Zheng casually kowtowed Guazi and said, "What can I do?"
Chapter completed!