It's a pity that although she knows some basic principles, aluminum alloy, the material required for the outer layer of the bulb, is not so easy to smelt.

Even if it is smelted, it is not so easy to blow it into the shape of a illuminable bulb.

What's more, the students of this period did not consider the use of electric energy for lighting.

Although there is a talk about generators in the school palace, no one has come out of it yet.

I didn't worry too much about this, some things need to be opened to a certain extent before they can succeed.

She didn't want to do that stupid thing that plucked the seedlings and fueled them.

Now seeing the limitations of lantern lighting in the palace, Xu Yan finally began to miss the modern electric lights.

It's no wonder that she didn't think of these until now, but in the past, she had basically entered the Academy of Agricultural Sciences at this time.

There is nothing lacking in the Academy of Agricultural Sciences, so in reality I don't care so much.

"Your Highness, you're back."

Just as she was thinking about how to guide the students of Xianyang Academy to invent electrical appliances, a voice woke her up.

"Ah, it's Zhang Han."

Xu Yan turned around and looked in the direction where the voice came from, and saw Zhang Han coming from not far away.

Zhang Han nodded: "The minister is preparing to go to Cuiwei Hall to meet His Highness." ”

"Is the search of the idle temples over?"

When she heard this, she immediately thought of something and asked with a smile, "Tell me, what did you find?" ”

Zhang Han's expression was slightly solemn, and he looked around, and then said, "Your Highness, please discuss this matter in another place." ”

"Okay, follow me."

Xu Yan didn't say much, and took her back to Cuiwei Hall directly.

The personal maids hurriedly served tea and poured water, and were ordered by His Highness to withdraw from the rear.

Xu Yan motioned for Zhang Han to drink tea first, and then motioned for him to speak directly.

has been by Xu Yan's side for so many years, and Zhang Han is also used to having something to say.

"Your Highness, the ministers have searched all the idle palaces, and there are two or three secret passages under five of them."

When Zhang Han said these words, his face was extremely solemn, "The minister personally went down to observe, and several of them were used to shuttle between the palace. ”

"And there are three that are going to the outside of Huazhang Palace, and the specific directions, the minister has not yet calculated, and he is going to send someone through overnight to see clearly."

"Don't be in a hurry to do such a dangerous thing at night. ”

"Let people guard the secret passage, and it's not too late to explore it at dawn. Those secret passages that travel through the interior are supposed to have been arranged by some people who lived here in the past. ”

"There's no need to worry too much."

Speaking of these, Xu Yan's expression became unconsciously solemn.

"As for those passages to the outside world, they must be carefully explored, and the enemy must not be allowed to take advantage of this loophole."

"Please rest assured, Your Highness, the minister has arranged for someone to block the internal passage in time."

Speaking of this, Zhang Han was a little more confident, "The minister has also sent someone to guard the entrance of the passage to the outside world, so he will send someone down when he gets permission from His Highness." ”

Having said this, Zhang Han's expression became a little more solemn.

He took a deep breath before he said truthfully: "Although the ministers did not find suspicious people in the rest of the palaces, there are some suspicious people among the palace maids in Huazhang Palace who need to be supervised. ”

"Then it's regulated."

Xu Yan heard the meaning of Zhang Han's words, and immediately asked, "Is it something in an important position?" ”

"Yes, Your Highness, there is one paper mill, two weapons workshops, and two from the Ministry of Agriculture."

"Isn't there one in the dining room?"

After listening to Zhang Han's words, he didn't mention the dining hall, and he was a little surprised.