Huang Zicheng shook his head and gave a lecture on the stage, recently it has been the historical records he has been talking about, Zhu Yunxi in the audience is full of spirit to listen, Zhu Yunxi and Li Jie behind him have a sleepy expression, since he and Huang Zicheng tore their faces, Li Jie no longer pretends to be a good student, anyway, he and Huang Zicheng are both companions, and the two are equal in terms of identity.

finally waited for Huang Zicheng to finish the class, and Zhu Yunxi chased him out to ask some questions he didn't understand, but Li Jie and Zhu Yunxi stretched their waists, and their spirits came back all of a sudden.

"Li Banyu, when will your hot air balloon be repaired?" Zhu Yunxi turned around, stared at him with bright eyes and asked, since he saw the hot air balloon, he has been thinking about it, and he dreamed that he also flew into the sky in a hot air balloon.

"It is estimated that it will take a few days, in addition to repairing, we will also make some improvements to it, and then Qin Tianjian will come to test the flight, and when the performance is stable, we will make more hot air balloons, maybe His Highness may also fly into the sky with it in the future." Of course, Li Jie understood Zhu Yunxi's thoughts, so he said with a smile.

"Really, when will I have to wait until I get on the hot air balloon?" Zhu Yunxi was also very excited when he heard this, and asked again.

"I can't say for sure, maybe a month or two, maybe a year or two, after all, if His Royal Highness wants to get on the hot air balloon, he must get the consent of the crown prince and even His Majesty." Li Jie spread his hands and replied helplessly, after all, hot air balloons are risky, even if they improve their safety in the future, but with Zhu Yunxi's identity, I am afraid they will not be able to easily get into danger.

"Do you want your father or even the imperial grandfather to agree? Then I'm hopeless! Zhu Yunxi said loudly in despair when he heard this.

Li Jie knew that Zhu Yunxi would have this kind of reaction, only to see him smile calmly again: "Actually, compared to hot air balloons, I have a more interesting thing here!" ”

"What's that?" When Zhu Yunxi heard this, he immediately sat up straight and asked.

"This is it!" Li Jie said as he took out a delicate copper pipe from his sleeve, and when he opened it, it was a pair of clairvoyance, but this was not made by him, but the first batch of experiments made by the claireye's workshop.

"What is this?" Zhu Yunxi has never seen clairvoyance, let alone knows its function, in fact, let alone him, even some generals in the army have never heard of clairvoyance, because this thing is still kept secret for the time being, and it will not be equipped in the army until mass production in the future.

"This is called clairvoyance, also called telescope......" Li Jie simply told Zhu Yunxi about the role and usage of clairvoyance, and took him to the window, and let him personally experience the magic of clairvoyance.

"Wow~, I really saw a long way away!" When Zhu Yunxi saw the distant scenery through the telescope, he also screamed exaggeratedly, with a look of disbelief on his face, he didn't expect that the clairvoyance in myths and legends could really be realized.

"Li Banyu, I want to see the scenery outside the imperial city, but it seems to be blocked by the city wall!" Zhu Yunxi held clairvoyance with one hand and grabbed Li Jie's sleeve with the other, and said eagerly.

"Then we can only find a higher place, as the so-called standing tall can see far." Li Jie smiled again and said, for him, the scenery outside the imperial city is nothing to see at all, but for Zhu Yunxi, who grew up in the deep palace, outside the city is the place he yearns for the most, although Zhu Biao took them to the Ordnance Bureau yesterday, but the entry and exit were in the carriage, and he took a few turns around the Ordnance Bureau at most.

"Let's go to the library, it's relatively high, and you can definitely see the outside of the city!" Zhu Yunxi also immediately thought of a place when he heard this, and then pulled Li Jie and ran out.

The so-called book building, in fact, is the library building, Nanjing here supervises the Yangtze River, the waterway is vertical and horizontal, resulting in the air is relatively humid, so the books are also easy to be damp and moldy, the main hall here in order to collect books, specially built several tall book buildings, a total of three floors, the upper two floors are specially used to store books, so that some moisture can be isolated.

The two of them quickly climbed to the third floor of the study building, and when Zhu Yunxi raised the binoculars again, he could really see some scenery and characters outside the city beyond the city wall, especially the bustling crowd on the street, although it was too far away to see it really, but it was enough to make him feel very novel.

Zhu Yunxi felt that everything was fresh outside the city, and after a while, he put down his clairvoyance and said to Li Jie excitedly: "Sir, if we fly in the sky in a hot air balloon, will we see more clearly?" ”

"Of course, when flying in the sky and looking down, the entire capital is like a chessboard, people, chariots and horses are like chess pieces on the chessboard, and this clairvoyance was originally equipped for the generals in the army to observe the situation on the battlefield." Li Jie replied with a smile again, but there seemed to be a lot of hints in his words.

Zhu Yunxi is very smart, plus he just watched the drill of the musketeers yesterday, and now he also showed a contemplative look when he heard Li Jie's suggestive words, and after a while, he asked tentatively: "Sir, if on the battlefield, the general flies in the sky in a hot air balloon, and then holds a clairvoyant, can he grasp every move of the enemy on the battlefield?" ”

"Huh? yes, I didn't expect you to think of that! Li Jie immediately praised with great joy.

"Does it matter?" Seeing Li Jie's exaggerated appearance, Zhu Yunxi also asked with some uncertainty.

"Of course, although the hot air balloon was invented by me, but its use is still being explored, and now it is only by Qin Tianjian to ride it to the sky, so as to observe the celestial phenomena and geography, in addition to this, I have not thought of its other uses, but after your reminder, it has given the hot air balloon an additional military use." Li Jie praised again with a happy face.

Of course, Li Jie is acting, since yesterday he took Zhu Yunxi to watch the musketeer drill and visit the hot air balloon, plus he gave him clairvoyance today, as well as the verbal hint just now, he did this to make Zhu Yunxi think of the military use of hot air balloons, after all, he has already prompted it so clearly, if Zhu Yunxi can't think of it again, then it will really be hopeless.

"Really?" Zhu Yunxi didn't feel that there was anything special about his thoughts, but seeing Li Jie so happy made him feel as if he had really discovered something great, which made him feel a wave of pride and confidence in his heart, and his small body couldn't help but straighten up.

"Of course it's true, since it was Your Highness that you thought of, why don't you write an article on the military use of hot air balloons, write everything you think of on it, and then hand it over to His Royal Highness the Crown Prince to watch, I believe he will be very happy!" Li Jie spoke excitedly again, but this time he simply changed from implicit to explicit.

"Father will really be happy?" Zhu Yunxi asked again in disbelief.

"Of course I like it, don't forget, I only became the prince's companion with hot air balloons and clairvoyance, even I didn't expect a question, you actually thought of it, the prince will definitely be impressed by you!" Li Jie agitated again.