Mr. Xue saw that Princess Pingyang didn't let the pretty girl avoid him, so he didn't say much and simply said, "General, this student is lacking in manners."

As he spoke, he stood up, took the paper and spread it out, explaining:

"This is a three-bow composite bed crossbow." A three-bow composite bed crossbow has a maximum range of two thousand paces. "The advantage of the bed crossbow is that it has great range of fire, great strength, and can destroy the walls of the city in one shot. It can be used to defend the city or to attack the city; the disadvantage is that there are many people needed to operate it, making it inconvenient to move around."

Then, he took another drawing and continued to explain: "God Arm Crossbows have a range of 240 steps or higher. It can be used by a single person and can pierce through two layers of armor. When I heard that General Princess carried the heavy responsibility of guarding Weize Pass, and was the gateway to Tang Dynasty, and rejected the Hu, and resisted the internal strife of bandits, and had no way to repay the grace of saving one's life, I felt extremely uneasy in my heart.

Princess Pingyang was also one of the leaders in the battle. She understood the benefits of this piece of paper the moment she heard it. Her eyes, which had been calm and composed the entire time, finally brightened up a little as she looked at Mr. Xue: "This drawing is also quite novel, can my husband give me some pointers?"

"This is called drawing with three views. It's a drawing made from looking at an object from the same angle, looking down, and looking at it from the left. Princess, please look …"

Mr. Xue walked up and spread out the blueprint, explaining in detail to Princess Pingyang how to look at this blueprint.

Mr. Xue had learned painting from a young age and was very interested in design. Although he didn't go to college, he did learn a lot of things on his own.

Princess Pingyang held the blueprint, and her delicate white fingers lightly touched the paper: "This piece of paper is also different from the ones my Tang Dynasty usually uses, the brush and ink also have some peculiarities, are there any differences in the manufacturing techniques?"

Mr. Xue had seen the red paper given by the licorice, but he didn't know if there was any difference between writing and writing: "Please show me the commonly used paper."

Princess Pingyang pulled out a piece of paper from the table and handed it to him.

Mr. Xue learned painting. In the past, when his parents hadn't had any accidents, when he was learning to draw from his teacher, his teacher brought him to the first class with him. When he was out drawing, he often brought Mr. Xue to visit various places where traditional crafts made paper. The teacher often talked about how one could learn how to draw without understanding the contents of a piece of paper.

Mr. Xue touched it and took a quick look before understanding, "Princess usually uses hemp paper, the main ingredient is hemp plants, the student's paper is brown paper, and the main material for making paper is bark. As for pens, the students painted with pencils, and the one with the notepad was a pen. In our class, the brushes are called soft brushes, the pens are called hard brushes. Only those who pursue calligraphy and calligraphy will be able to write their words easily and quickly. "

Pen Mr. Xue had a pen with him. He took it out of his pocket, handed it over and told him how to unscrew it.

Princess Pingyang tried writing something on the paper. It was crooked and she was obviously not used to it. However, the benefits and convenience of this pen were obvious at a glance.

Princess Pingyang nodded, put down the blueprint, and picked up the telescope. "What is this?"

Mr. Xue: "This is called a high power telescope."

"Telescope? Was this used to climb high? However, what do you mean by high? "

Mr. Xue explained what a high power telescope was. Luckily, he did not buy one with night vision. If he did, it would be useless the moment he teleported. He would not have battery life!

"This item is quite useful in the army."

Princess Pingyang could see the benefits in a single glance. Mr. Xue laughed, "It is indeed useful. Along the way, we avoided a lot of dangers because of this. Otherwise, not to mention returning to the Central Plains, even surviving would be a problem."

Princess Pingyang nodded. She was in no hurry to test it out. Instead, she asked Mr. Xue, "This item is quite marvelous. Does my husband know how it is made?"

"The principle of the telescope is very simple. It is the principle of using the light of the lens and the imaging of the small holes. The theory was not difficult, but the problem was the materials! When a student looked at the telescope, he could roughly see the distance and size, and the most important part was the lens! Right here! The quality of the lens is related to the clarity and proximity of the objects observed. The distance needs to be calculated. "

"Calculate?" "How do we calculate that?"

"This is very simple. Just use a formula."

Mr. Xue loved to ride, occasionally he would climb a mountain or something like that. Telescope was a must, and the distance measurement was taught to him by his girlfriend's brother. The unmade uncle was from one of the departments in the army, and was more suited to Mr. Xue. Many of Mr. Xue's playthings, such as sabers, medicine, etc, were all given by him.

Picking up a piece of paper, Mr. Xue took out a pen and wrote down the formula. He gave an example and casually wrote down the numbers — —

"Wait!"

Princess Pingyang stopped Mr. Xue and pointed at the numbers on the paper. "What does that mean?"

Mr. Xue slapped his forehead. He remembered to write Chinese character numbers in drawing. Now that he was going to calculate a demonstration, he would habitually write Arabic numbers.

"This is a number, the writing style of the machine. Because writing, learning, and calculating are more convenient, it was also changed from the way it was written in the past."

As he said that, he wrote out the corresponding Chinese characters and numbers, making it clear at a glance.

Princess Pingyang held the piece of paper and read it without saying a word. She took out another piece of paper for Mr. Xue and let him calculate the numbers on it. The numbers were written in Chinese characters and were read in her hands. Writing a calculation demonstration was very quick. It only took a short while, but with the examples given together, it was easy to understand what was going on.

Princess Pingyang took the two pieces of paper and placed them on the table. She covered them with her hand and asked directly, "Did you learn all of these at the Fu Lang Machine?"

"Yes." According to the local system, children are enrolled at the age of six and are divided into primary, secondary and university levels. Primary school six years, secondary school divided into junior high school and senior high school, three years each. "In addition to learning the classics of sages, one also needs to study mathematics, physics, chemistry, and other subjects."

When Mr. Xue said this, not only Princess Pingyang, but even the beautiful lady showed an interested expression. Her graceful eyes turned and she interrupted, "Mathematics, as the name implies, is an index calculation, while physics is a way to understand things, isn't it?"

"Exactly. May I know how I should address you, my lady? "

When they were in Sui and Tang Dynasties, they called young women their wives. Mr. Xue knew this common sense, so he wasn't afraid of making mistakes.

"This is my female official, Lady Liu."

"So it's Lady Liu." "The contents of math and physics studies are just as Lady Liu said."

"What is it about chemistry?"

Lady Liu asked curiously. Mr. Xue answered with a smile, "It's the principle of studying the change of objects. For example, why would copper artifacts be rusted? What are the differences between acids and bases? What kind of reactions and changes would acid and base produce when they come into contact with different objects? "

Lady Liu was obviously a studious person, and when she heard Mr. Xue's words, her face was full of desire. "There are people who study these things in this world, I really want to take a look." Does Mr. Xue have books? "

Mr. Xue smiled, "There are no books available. "Wait for me to settle down, I can write it out."

Mr. Xue, who could even remember the website, had a much deeper memory of the chemistry books he had learned, so it wasn't difficult to write them.

He had probably never heard of someone coming from such a far place. Looking at Mr. Xue's talking, dressing, and actions, they were all different from Tang resident.

Lady Liu asked a lot of questions, starting with food, clothing and living arrangements. Mr. Xue answered as many questions as he could with the modern situation. If he asked something he didn't know, he would just say that he didn't understand it. The omniscient is God, not man. If you brag too much, you will break. If you act too arrogantly, you will be struck by lightning.