Xue Lang saw that Princess Pingyang didn't let the beautiful woman avoid it, and he didn't say much, so he simply said: "General, the student is rude." Pen %Fun %Pavilion www.biquge.info"

As he spoke, he stood up, took the drawings and spread them out, and explained directly:

"This is a three-bow compound bed crossbow. Three-bow composite bed crossbow with a maximum range of up to 2,000 steps. The advantage of the bed crossbow is that it has a long range and great power, and the rammed city wall can also be destroyed under a single shot, and it can be used to defend and siege the city; The disadvantage is that the operation requires many people and is inconvenient to move. ”

After speaking, he took another drawing and continued to explain: "The Divine Arm Crossbow has a range of more than two hundred and forty steps, and can shoot through two layers of iron armor when operated by a single person. Hearing that the princess general took on the important task of guarding the reed Ze Pass, as the gateway of the Tang Dynasty, rejecting the Hu people outside, resisting the rebels inside, and the grace of saving lives could not be repaid, the students were uneasy, but they had no long things, if the princess could use these two drawings, it would really be good. ”

Princess Pingyang is also the one who leads the troops to fight, and she understands the benefits as soon as she hears it, and her eyes, which have been calm and calm, finally have a little more energy, and she looks at Xue Lang with burning eyes: "The drawing method of this drawing is also quite novel, can Lang Jun give me some advice?" ”

"This is called the three-view drawing method, which is the figure obtained by observing an object from the head-up, down-looking, and left-hand view, princess, please look at ......"

Xue Lang stepped forward, spread out the drawings, and introduced to Princess Pingyang in detail how to look at this picture.

Xue Lang has been painting since elementary school, and is very interested in design majors, and although he did not go to university, he also taught himself a lot of things.

Princess Pingyang pinched the drawings, and her slender white fingers gently touched the paper: "This paper is also different from what I commonly use in Datang, and the pen and ink are also strange, is there a difference in the manufacturing process?" ”

Xue Lang had seen the red paper given by licorice, but he didn't know if there was a difference in the writing paper: "Please take a look at the commonly used paper." ”

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

Xue Lang learned to paint. When his parents didn't have an accident, when he was learning painting with the teacher, he was taken by the teacher to learn all kinds of paper in the first class, and when he went out to sketch, he often took Xue Lang to visit various traditional crafts and paper-making places. Teachers often say that if you learn to draw, you can't understand paper.

Xue Lang touched his hand, and after a glance at the light, he understood: "The princess usually uses hemp paper, and the main ingredient is hemp plants; Student: This paper is parchment, and the main material for making paper is bark. As for pens, students use pencils for drawing, and pens for writing their names. In our country, the brush is called a soft pen, and the fountain pen is called a hard pen. Only those who pursue the art of calligraphy write calligraphy, and the commonly used pen is a hard pen, which is convenient and fast to write. ”

Fountain pen Xue Lang had a fountain pen that he carried with him, took it out of his pocket and handed it over, and told him how to unscrew the pen cover.

Princess Pingyang tried to write on paper, but she was crooked, obviously not used to it. However, the benefits and convenience of this fountain pen can be seen at a glance.

Princess Pingyang bowed her head, put down the drawings, and picked up the binoculars: "What is this?" ”

Xue Lang: "This is called a high-powered telescope. ”

"Telescopes? Is this used to climb high and look far? But what is high multiplier? ”

Xue Lang explained again what a high-powered telescope is. Fortunately, he didn't buy one with night vision, if he bought one with night vision, it would basically be scrapped as soon as he crossed, and there was no battery!

"It's useful on the march."

Princess Pingyang saw the benefits at a glance. Xue Lang smiled: "It's really useful, because of this along the way, I have avoided a lot of dangers, otherwise, let alone returning to the Central Plains, even if you have a problem with your life." ”

Princess Pingyang nodded, and was not in a hurry to try it, but asked Xue Lang: "This thing is quite wonderful, does Lang Jun know how it is made?" ”

"The principle of the telescope is very simple, it is the principle of using the light refraction of the lens and the image of the small hole. The principle is not difficult, the problem is the material! When the student looks at the telescope, he can roughly measure the distance and size, and the most important of them is the lens! This is it! The quality of the lens is related to the clarity and distance of the observed things, and the distance is calculated. ”

"Calculations? How is it calculated? ”

"It's very simple, just use a formula."

Xue Lang loves cycling, and occasionally climbs a mountain or something, a telescope is a must-have equipment, and the distance calculation is taught to him by his girlfriend's brother. The eldest brother who didn't make it was from a certain army department, and he was more deed to Xue Lang, and Xue Lang played many things, such as sabers and medicines, all of which he gave.

Pulling over a piece of paper, Xue Lang took out a pen, wrote down the formula, gave an example, and wrote down the numbers casually-

"Wait!"

Princess Pingyang stopped Xue Lang and pointed to the numbers on the paper: "What does this mean?" ”

Xue Lang patted his forehead, he remembered to write Chinese characters and numbers when drawing, and it was customary to write Arabic numerals when he wanted to calculate the demonstration.

"This is a number, the way the franc machine is used to writing, because it is more convenient to write, learn, and calculate, so the previous way of writing has also been changed."

As you speak, you can see the corresponding kanji writing and numbers at a glance.

Princess Pingyang took the paper and looked at it, but didn't speak, and directly took out a piece of paper for Xue Lang again, and asked him to calculate on it, and the corresponding numbers and Chinese characters were held in her hand to read. Writing a calculation demonstration is very fast, but it takes a while, and you can understand it at a glance with the examples given.

Princess Pingyang received the two pieces of paper together, put them on the table, covered them lightly with her jade hand, and asked directly: "These are all learned in the Franc machine?" ”

"Yes. According to the local system, children enter school at the age of six, and are divided into elementary school, middle school, and university. There are six years of primary school, and the middle school is divided into three years of junior high school and three years of high school. In addition to studying the classics of the sages, they also have to study mathematics, physics, chemistry and other courses. ”

As soon as Xue Lang said this, not only Princess Pingyang, but even the beautiful woman showed an interested look, turned her eyes, and interjected: "Mathematics, as the name suggests, is the study of exponential calculation, and physics is the principle of learning from things, right?" ”

"Exactly. I don't know what this lady is called? ”

In the Sui and Tang dynasties, young women were generally called Niangzi. Xue Lang knows this common sense, and he is not afraid of making mistakes.

"This is the female official of the main palace, the Liu family."

"It turned out to be Lady Liu. The content of mathematics and physics is similar to what Ms. Liu said. ”

"What is chemistry?"

Lady Liu asked curiously. Xue Lang replied with a smile: "It is the principle of studying the changes of objects. For example, why bronze objects rust, what are the differences between acids and alkalis, and what reactions and changes occur when they come into contact with different objects. ”

This female official Liu is obviously a studious person, and when she heard Xue Lang say this, her face was full of fascination: "There are still people in the world who study these knowledge, I really want to see it." Does Xue Langjun have any books? ”

Xue Lang smiled: "There are no ready-made books." Stay down and settle down, but you can write it. ”

Xue Lang, who can even remember the URL clearly, naturally has a deeper memory of the chemistry books he has learned, and it is naturally not difficult to write it.

I have probably never heard of someone coming from such a far away, looking at Xue Lang's conversation, clothes, words and deeds, all different from the Tang people.

Lady Liu asked a lot of questions, starting from food, clothing, housing and transportation, the questions were also varied, Xue Lang tried his best to answer in combination with the modern situation, told what he knew, asked about the areas he didn't understand, and frankly told himself that he didn't understand. It is God who is omniscient and omnipotent, not man. If you brag about it, it will break, and if you pretend to be big, you will be struck by lightning.